Touhou/WMG

Wild Mass Guesses about  include:

Gensokyo is Reimu's childhood fantasy
Reimu really is the miko of her family's small, run-down shrine, but only in our world. With this comes an awful lot of free time and boredom around the shrine. In order to keep herself entertained, she thought up Gensokyo as a small child, as well as the characters, as something akin to imaginary friends in an imaginary setting. Perhaps influenced by real people and real events, Gensokyo, its residents, and the happenings that occur there are just as exaggerated and wacky as you might expect from the mind of a little girl with not much else to do. This would also explain the increase in complexity and refinement as the series has progressed - Reimu's grown up and thinks more clearly and in greater detail.
 * Perhaps Marisa is a friend of Reimu's, made after Gensokyo's initial conception, and then later playing "make-believe" together with Reimu.
 * This would logically explain what happened to the PC-98 characters. With so many imaginary friends, it's only natural that many would end up being forgotten or discarded. Some would be remembered in time, but most would vanish from memory.

Satori and Koishi are the eye-heart-things
And the bodies are just hosts Orin has brought them.
 * Following this through, the eye-heart-things are actually Soul Gems. Yukari pulled them out of PMMM For the Lulz and in doing so . Would also go some way to explaining their abilities, if they wished to understand people. Koishi's power breakdown could be seen as the first stage in  . But yeah, this is weird even for me.

Patchouli Knowledge doesn't bother fighting Reimu and Marisa at full strength.
Seriously, Gensokyo has a Gameboy. They MUST have some sort of vitamin supplement. Also, Patchy's reasoning is rather nonsensical.
 * I won't argue the existence of such things, but remember, Patchouli's a borderline Hikikomori. She wouldn't ask Koa to get them, Sakuya probably wouldn't volunteer since she needs to be at the Mistresses' beck and call, and the Scarlets themselves don't go outside very much themselves.
 * Sakuya can bend space-time at will. I doubt getting vitamin pills would be very hard.

Patchouli doesn't have asthma; it's the drain of having Koakuma as a familiar.
Devils (Horny or otherwise) are more Mana gluttons than shikigami. Patchy can maintain it indefinitely, but it gives her a more delicate constitution.
 * She keeps it up because she's grown to like Kaokuma (or is dependant on her; for Darker and Edgier A Us) and it's a symbol of status.

The Kappa are really Genre Savvy humans.
They have the best accessible technology in Gensokyo; they're on friendly terms with most factions; and have the direct good diplomatic relations with a goddess. They were humans who realized that calling themselves "humans" is painting a bullseye. So they looked around, picked a species that wasn't in Gensokyo; put on bathing suits and called themselves "Kappa." And then they deliberately stayed out of causing direct incidents, but did trading and negotiation to profit.
 * Kanako knows, but as long as they give their faith to her; she's not telling anyone.
 * Building Hiso Tensoku is an exception to the "staying out of direct incidents", however.
 * "Direct" in this case meaning "blatant enough to warrant an asskicking from somebody."
 * They got over excited when they watched giant mecha shows brought over by Sanae.

The Moriya Shrine is for REAL on our side of the Fourth Wall.
Kanako asked ZUN to place herself, Suwako, and Sanae into his series, in order to drum up more faith in OUR world. Yukari met her during a drinking session (see another WMG below concerning Yukari and ZUN's drinking friendship), and they agreed that it was a good idea.

Now, while the Moriya Shrine gains fans in the game (benefitting ZUN), the real Shrine on our side of the fourth wall enjoys more pilgrimages and more faith (helping Kanako). Just as planned.

The Hakurei Shrine is for REAL on our side of the Fourth Wall.
Same as above—only this is the origin of Touhou itself. Just replace the Moriya Shrine crew with Reimu and "faith" with "donations."
 * Confirmed...in a manner of speaking. Strange and Bright Nature Deity has Reimu explaining that the Hakurei Shrine is the Wall between the Outside World and Gensokyo. A Wall belongs to neither side; and both at the same time.
 * Oriental Sacred Place has the Hakurei Shrine receiving mysterious offerings that include wine. Presumably ZUN knows the true location of the Shrine, and converts some of his "donations" into things that Reimu can use, since modern Japanese Yen has no trade value inside Gensokyo.

Yukari is the final form of the Portal Gun
Seriously, think about it.

Yukari is the genderbended version of Louis Cypher
Both are blond. Both are secretive. Both are Chessmasters...What else there's to say?
 * Both are Chaotic Neutral (Louis is more of a YMMV)?
 * Could be... it sounds to...true.
 * Mabye they play chess in the weekends?

KirbyM is male.
There are simply more male fans than female fans.
 * "Kirby" is a masculine name.

KirbyM is female.
The "self-insert" character in the "Daily Flashes," Unnamed Character, is female.
 * The posts themselves have a generally more feminine tone.

KirbyM is a waffle-based robotic life form.
KirbyM is quite obviously a robot, this has been proven by science.
 * Alternatively, KirbyM is an AI.
 * "Walfas" sounds kind of like "Waffles".
 * Acknowledged and explained at the end of the old "about page.

The PC-98 characters are actually recovering from serious injuries.
Fact: the purpose of the Spell Card rules is to allow duels without causing death or serious injury. Fact: the Spell Card rules were invented between Mystic Square and Embodiment of Scarlet Devil. One can easily conclude that, before the Spell Card rules were in place, the youkai of Gensokyo (who are extremely difficult to kill to begin with) were, in fact, seriously injured.
 * Alternatively, they all escaped into Makai to flee the crazy shrine maiden and black white witch, except Alice (for Marisa) and Yuka (cause she's nuts). Now that Reimu and Marisa went back into Makai...
 * Or maybe they left in protest of the Spell Card rules.

The Grimoire of Alice is a Lost Logia Tome.
Apart from the usual incredible power possessed by the book, it also gifts its bearer with longevity. It's also part of the reason she left the Makai, as it was part of an Incident that estranged her from Shinki.
 * Must I take this to its logical conclusion?
 * Given the above and the fact that Marisa feels the need to point out that her Grimoire isn't a copy of Alice's, I'd say it's the Book of the Night Sky prior to being corrupted.

A bare head on a woman is considered indecent in Gensokyo.
It probably isn't as bad as e.g. going topless, but it's still probably considered somewhat rude. This would explain why virtually every character in the series wears a hat, hair-ribbon, or something else on their head. The exceptions:
 * Petting Zoo People with no other hats (e.g. Tewi Inaba, Yuugi Hoshiguma); this is probably justified in that they're like Felicia, who has strategically-placed fur-patches.
 * Kaguya Houraisan, Sara, and Yumemi Okazaki (respectively from the Moon, Makai, and the Outside) are from different worlds with separate cultures, in which this taboo doesn't exist. The same might apply to Parsee Mizuhashi; the Underground is divorced enough from the surface world that there are probably plenty of cultural differences.
 * Kogasa Tatara possibly hopes her umbrella will suffice. That, or she wants to surprise people with this behavior.
 * Yuuka Kazami is badass enough that she just plain doesn't care.
 * If that doesn't cut it, she's got those pajamas, complete with night cap.
 * Byakuren Hijiri has been sealed away for so long that she probably doesn't know that times have changed. The same can be said for Nue Houjuu.
 * Parsee Mizuhashi doesn't have a hat, and is therefore incredibly jealous of others.
 * Since her Pointy Ears have apparently ascended into canon as of Wild and Horned Hermit, Parsee may no longer need extra accessories quite as much as she thinks.
 * This theory really isn't all that unrealistic when you realize that some cultures actually DO state that women showing their hair is indecent. That's why they have to wear veils.
 * In fact, Lolita fashion is based partly on Victorian England... in which going hatless WAS socially improper.

Yukari Yakumo had a hand in starting the Hakurei bloodline.
Her ultimate long term but somwhat plausible plan: Yukari had seen how the world of human civilisation would eventually eclipse the Old Races in terms of power and progress - the series of events that led to the Oni people moving away was merely a sign of worse things to come.

As she did not want the destructive conflicts that would result, and wanted a land where youkai could live in relative peace without decidedly intolerant monks and exterminators making trouble every so often, she decided to find a way to influence a family of priests. By manipulating their bloodline, she laid the foundations for the powerful Hakurei family of priests and Miko to form in the future, their powerful Sealing Arts holding traces of her power to create Borders or Boundaries.

This is the other reason why she likes to mess with Reimu in a playful and good-natured way, as the current Hakurei Miko is a one of her greatest success stories.
 * This Troper doesn't get how any youkai could peacefully live near that maniacal shrine maiden.
 * A donation or two goes a long way - Reimu's only grumpy because of her lack of donations.
 * It's actually true. In one of the Nature Deity stories, Yukari gives Reimu food. Marisa playfully accuses Reimu of accepting bribes.
 * As a corollary to this, Yukari took care of Reimu when she was younger. Reimu might not remember her youkai guardian, but that just makes it easier for Yukari's Wife Husbandry plot.

ZUN is in fact retelling the tales of Gensokyo accurately.
Yukari is always visiting him with all the information he needs, whether its gossip, the Bunbunmaru, or Akyu's historical records. How else do you think he got this much detail? For all that this artist's portrayal shows, it may well be how Zun gets everything so right. Possibly Yukari is his drinking buddy.
 * Yukari enjoys playing along so much, that when ZUN makes stuff up, she starts fooling around to make the made-up stuff happen.

Yukari Yakumo is all-powerful, and could transform people or read minds if she wanted.
Yukari has the power to "manipulate boundaries", a vaguely-defined skill if ever there was one. Furthermore, this includes abstract concepts such as the boundary between night and day, or between life and death, or between mountain and sky. With a list like that, you could make a case that there's not much that can't be considered a boundary. Between one mind and the next? Why not read minds! Between one second and the next? Control time! Your body's a boundary between your soul and the outside world? Even better for transformation! As for why she hasn't displayed any abilities like this, i.e. to singlehandedly solve the lunar crisis in Imperishable Night: she's already known to be lazy. For instance, she hasn't gotten around to fixing the hole she made in the barrier between the living world and the afterlife as of Perfect Cherry Blossom.
 * Alternatively, she hasn't discovered that she has these abilities. Mastering one's skills in Touhou's backstory involves dedication and practice, and Yukari is, as we said already, lazy. Too lazy to get off her butt and practice bending reality to her whims, even if it means the key to omnipotence? Very yes.
 * This quote from her entry in Perfect Memento in Strict Sense would indicate that she already figured everything out. "Rumor has it that she is a youkai from outside, and she simply comes to here for play. Indeed, she may spend the winters and the daytime, when she claims to be sleeping, in the outside world, and some even say that the outside world is Yukari's dream."
 * If we are a dream for the reality warper, I think it's about time we turned into a nightmare.
 * Which ties in nicely to the theory about Maribel below.

Yukari Yakumo in fact can make herself or anyone a real person and a fictional character, and actually most people from Gensokyo are missing people from different parts of our multiverse
Gensokyo is the "land of illusions" and she canonically has wandered outside. All she does is manipulate the border of real and fiction. This also includes browsing through the internet and drinking with ZUN.
 * This is how the human population in Gensokyo is maintained. We've only heard about one village, not really enough to be self-sustaining for generations without inbreeding; and there doesn't seem to be any honor given to humans strong enough to protect them. Yukari pulls in enough humans to keep the diversity of the stock up. The relatively recent Pax Reimu has lowered the need for this slightly.

Aya Shameimaru is ZUN's girlfriend.
Seriously. How else do you explain the fact that she's in every official Touhou game from Phantasmagoria of Flower View on? She has to be either offering him sexual favors, or sweet-talking him with "Ooh, can I be in this game, too?" at regular intervals.
 * She's always either defeating the opponents without realizing it in PoFV, defeating the opponent by taking pictures of them in a spin-off game, to holding back in the most recent game. Then again, Aya is quite popular with the target demographic...
 * In said spin-off game, she outdoes the series' main character Reimu Hakurei in defeating not only more characters in a single game than Reimu has so far, but defeating notorious opponents such as Eirin, Shikieiki, Flandre, Yukari, Mokou and Suika. Not to mention that Shikieiki conjures, as her final attack, Aya's mirrored image against her, and although this mirrored image does use bullet barrages like any of the former and latter opponents, Aya defeats it. By taking pictures of it.
 * Where was it stated that Aya actually defeated anyone in Shoot the Bullet? I thought she just got the pictures she needed and that was it - almost like a photo shoot. After all, the danmaku duels aren't in any way dangerous, and maybe getting hit causes her to lose any pictures she had.
 * Even if non-letal, I guess it hurts. Isn't it a good reason to dodge everything?
 * Vouching for that, in a manga Marisa mentioned that getting hit by a danmaku is like getting pelted with a ball or something. Also, she doesn't defeat them, she just takes their pictures and runs away.
 * I think Aya is a rare breed of Creator's Pet. Author favoritism plays hard on her, but she's THAT popular towards the audience, not utterly hated, she doesn't look like a Creator's Pet.
 * Aya, in her peak, did have quite a few detractors, and very vocal ones at that. But she also had a lot of fans as well. Her roles in the series have been reduced lately (she doesn't appear at all in Undefined Fantastic Object or Great Fairy War, and while she does appear in Hisoutensoku, she only does so if you have Scarlet Weather Rhapsody and has no role in any of the stories), and as a result, much of the hatred towards her has died down.
 * Not quite true. She's in one of Fairy Wars' ending (the one that leads to the EX stage, even), and she's mentioned in passing in UFO.
 * Aya was probably based off of a girl who did photography in the past that ZUN liked, or ZUN himself was into photography when he was younger and tried to create a character based off of his past experiences.
 * It looks like Sanae is also trying to close in on this territory as well. Stage 5 boss in Mountain of Faith, and extra stage mid-boss in Subterranean Animism. Who knows what's next?
 * Actually she's just another "stage 5 boss that appears in the next game", but instead of being a playable character she's a midboss.
 * Retracting my earlier point to say this, but Touhou 12 has been announced, and Sanae is indeed playable. Oh God, it's so scary when people are right.
 * Update: Sanae has been confirmed as playable in the third fighting game, Touhou 12.3. Look's like ZUN's been getting more action lately.
 * Now, Sanae has also been confirmed as a playable character in Touhou 13.
 * Due to ZUN's announcement on the latest Touhou game, Double Spoiler, Aya is back in action.
 * ...and Sanae's in it.
 * As an EX-Boss noless.
 * ...and Only One New Character, Hatate Himekaidou.
 * Well, come on, Sanae's a shrine maiden. It's the stated job of shrine maidens to deal with incidents. I think she's supposed to be the third main character.
 * Alternatively, Aya just brings ZUN lots of beer.
 * Wait, so with the announcement of Touhou 12.8, starring Cirno...
 * Squick nothing, he just adopted her.
 * Besides, she's over sixty.

Every single character is based on someone ZUN knows.
How prominent of an appearance a character has in a game reflects how much contact he had with them in real life during the making of that game. He never admits this to protect his friends from Loony Fans.

Obviously, he moved sometime between the PC-98 games and the Windows games. This explains why almost none of the PC-98 characters returned in the Windows games; the few who have either moved as well or are/were frequent visitors.

In fact, the entire series could be simply Life Really, Really Embellished!

Maribel Han and Yukari Yakumo are the same person.
The basic idea of this fan-theory is that when Maribel sleeps, she dreams that she's Yukari, and when Yukari sleeps, she dreams that she's Maribel. Detailed in her entry at the Touhou Wiki. It is also worth mentioning that there is no official romanization of her name, so that instead of "Han" her name might actually be "Hearn"—as in Lafcadio Hearn, a Western author who, after he gained Japanese citizenship, became known as Koizumi Yakumo.
 * Furthermore, Hearn was the first non-Japanese-born to have written extensively on youkai, so...
 * Alternatively, Maribel is Yukari's puppet, and the true Yukari is yet to appear. When Maribel sleeps, Yukari hijacks her body and gaps her into Gensokyo. When she's done with her, Maribel is sent back but gets to keep the partial memories of what has happened. Because Yukari thinks it's funny to do so.
 * Yukari is Maribel's future self, after fully crossing over to not-quite-yet Gensokyo, and due to the strange, fluctuating nature of border, she was sent into the past, like the note she penned found in PMiSS was. Once there, she becomes a youkai, and her ability to see boundaries evolves into the ability to control them, resulting in a Stable Time Loop as she goes on to create the Great Border, which leads her past/future incarnate self to see the world beyond it and long to be a part of it.
 * Perhaps present Yukari even has a role in Maribel becoming her past self, meaning that Yukari created herself.

Maribel and Renko are direct "real-world" analogues to Marisa and Reimu, respectively.
One's a flighty blonde with some sort of connection to magic, whose romanized name begins with "Mari." The other's a Japanese brunette with a certain interest in how her world works, and the hiragana of her name begins with "Re." The two are more or less inseperable, except when circumstance dictates. They Fight Crime. Which pair am I talking about?

Yuyuko's ability to kill involves death by Moe.
She's one of the cutest characters in the series, and her "unique" ability is simply to kill people. Why wouldn't her ability involve her cuteness!?
 * Alternatively, she just EATS THEM.
 * DEATH BY YUYUKO!
 * The 4koma series Life of Maid gives her this ability, and it is as effective as it is adorable. Poor Rinnosuke didn't stand a chance...

The bosses of Subterranean Animism each represent one of the Seven Deadly Sins, plus Satan.

 * Lust:.
 * Gluttony: Yuugi Hoshiguma, the stage 3 boss, is an oni, which means that she's a real drunkard.
 * Greed:
 * Sloth: Kisume, the stage-1 mid-boss, is a tsurube-otoshi—that is, a youkai who live atop trees, and when a human comes close to the tree, a bucket drops down and eats them. In other words, she sits around doing nothing until something really compelling happens.
 * Wrath: Yamame Kurodani, the stage 1 boss, is described in her profile thusly: "She has no qualms about fighting humans. She has a bright, combative personality." In other words, she's really easy to rile up.
 * Envy: We already knew that Parsee Mizuhashi, the stage 2 boss, was a personification of jealousy.
 * Pride:
 * Satan:
 * Except that she is not only downright clueless, but also the pet of a lesser boss.
 * Maybe thats why she is known as 6-ball.
 * I dunno, I think Utsuho would make a pretty good wrath or greed, what with her wanting to take over the world. Since the greed example's stronger than the wrath example, I'll slide her in there.
 * As a counter argument, I'll switch the Komeiji sisters' sins.

The next Touhou game will finally see the return of Mima.
Alright, bear with me. Most, if not all, of the endings from Subterranean Animism imply that, gave Utsuho the power of nuclear fusion for reasons as yet unclear. Considering what Utsuho was planning to do with that power, it's hard to imagine what possible gain there could have been in this. I'll tell you what: chaos. Mistrust. My fellow tropers, I put it to you that the plot of Touhou 12 will reveal that has been framed by the Scourge Charismatic Spirit of the Hakurei Shrine, as part of a larger plot to reassert herself as a power player in Gensokyo by stealing the Yin-Yang Orbs! Playable characters will include Reimu (natch), and Sanae ; Marisa's presence, due to possibly conflicting loyalties, is an X-factor. This WMG has been officially jossed. She's nowhere in sight in Touhou 12 and 12.3. It looks like Mima is once again left in the dust.
 * Point: The Moriya stooges are fresh out of a world that has electricity. I'm sure Kanako was just trying to rig up something to power Suwako's multitude of consoles. Air conditioning wouldn't hurt either.
 * Tangental Point: she could have always asked Yukari, who apparently owns a Gameboy as a result of Rinnosuke finding one in one of the non-game works, since Yukari seems to have unlimited access to electricity and even fuel for Rinnosuke's oil-burning heater.
 * Well, it is possible that Kanako just doesn't trust Yukari, and, consequently, doesn't want to become dependent on or indebted to her. Given the fact that Yukari is a rather shady character who has manipulated people in the past, such distrust would not be unreasonable.
 * That plot makes more sense for either Shinki or Yumemi.
 * And now it's been Jossed.
 * No, because Shinki is Byakuren and the mysterious ship she is using is Yumemi's.
 * Hm, Touhou 12 does feature Sanae as a playable character. Maybe it's all coming true.
 * Mima will forever be to return in the next (main) Touhou game. Regardless of whichever the current one is.
 * THIS JUST IN! Mima will cameo in Touhou 12.8! Or not. Still waiting for 13.
 * 13 is about Holy Spirits, so it's quite possible
 * Jossed AGAIN. Now we wait.

The next Touhou game will have Marisa and Reimu as the stage 4 boss, depending on the player character.
Works nicely with the above. It goes like this: in Lotus Land Story (that is, Touhou 4), the stage 4 boss is Reimu if you're playing Marisa, or Marisa if you're playing Reimu. In Imperishable Night (that is, Touhou 8), the stage 4 boss is Marisa if you're playing the Border Team or Ghost Team, and Reimu if you're playing the Magic Team or Scarlet Team. Going by the previous examples, it appears that every four Touhou games, the stage 4 boss is Marisa/Reimu, and the next main Touhou game will be number 12.
 * Refinement of the above: add Sanae to the list of bosses. The boss will be Marisa with Reimu-A, Sanae with Reimu-B (or vice versa), Reimu with Marisa-A and Sanae with Marisa-B, and so forth.
 * Actually, Reimu/Marisa had shown up as bosses in Phantasmagoria of Flower View. So much for that theory.
 * If we combine it with the theory above, Mima will be stage 5/final boss, and stage 4 is, once again, someone protecting her. Marisa is, by her nature, protecting her Master, and Reimu doesn't want the two of them teaming up again or there would be more mass chaos. The chain would be: Boss 1-2-3-Marisa-Shinki/Yuka?-Mima.

Meira and Mima are the same person.
Meira is the Stage 2 boss in Story of Eastern Wonderland. She's never seen at the same time as Mima, she appears shortly before Reimu faces off against Mima with what appears to be the same goal in mind (that is, she wants Reimu's power), and she's never seen again. Sounds suspicious to me!

Flandre is a humanized form of Marx.
The rainbow crystal wings, the batshit insanity, the colossal power they wield... how can they not be tangentally related?
 * Marx just acts insane, and his so called colossal power was rather pathetic (NOVA was deactivated beforehand, so justified). The wings however are the same.
 * Marx Soul, on the other hand, IS insane.

Justification for Fundamentally Female Cast: Gensokyo's nature as a land of illusion.
Look at it like this: Rinnosuke has firmly established that, if there is sufficient active disbelief in a given phenomenon—in his words, it is considered to be "illusory"—it is at least capable of existing in Gensokyo. Meanwhile, the outside world is a patriarchal society: the idea of women calling the shots is tenuous at best. The idea of a non-adult woman being in a position of power is even more "illusory." Thus, in Gensokyo, the land of illusion, just about everyone of any importance whatsoever is female, and on top of that, very few of them look entirely grown up. In fact, it seems that lately (i.e. from the first Windows game on), the only reason any male characters are significant is because they are male and we hear about them. This allows for Schoolgirl Lesbians, as well.
 * His theory is nowhere near as firmly established as some would like to believe. Too many things from the outside world, which decidedly do not depend on belief to exist, show up in Gensokyo—for example, outside humans who get lost in Gensokyo (not just abductees), and many of the items Rinnosuke's shop. That was part of the counterexamples from the main page; too many of Rinnosuke's curios are electronics which were current-generation (such as the Apple iPod) at the time of their discovery (with the exception of things like the Nintendo Gameboy). To be honest, Rinnosuke's theory may as well be Wild Mass Guessing of his own.

That said, outside of the obvious out-of-character explanation that the Lady Land is Author Appeal, males are known to exist in significant qualities in Gensokyo—they just aren't given the spotlight (with Rinnosuke, Unzan, and Genji being the exceptions as of this edit).
 * Technically... All of the electronics shown are future-generation, since Gensokyo "is in what the outside world would call the Meiji Era (1868-1912)" ("but there are many items that belong in subsequent eras"). Unless of course ZUN meant that Gensokyo is Set In The Wrong Era rather than running concurrent to the Meiji Era, and either he or the translator failed to express the proper meaning. [/nitpick]
 * Gensoukyou split off during the Meiji era, and has mostly stayed there technologically. The games are set roughly at the time of their release.
 * Perhaps the modern technology passed through Gensoukyo's border, or Reimu found it in her donation box. Canonically, the borders aren't as foolproof as they should be - Yukari's never fixed the hole Yuyuko formed in PCB, and Maribel can get through the border, as others possibly could.
 * If things exist in Gensokyo due to people not believing in them, things such as the Game Boy and iPod were items that were lost by someone in the real world, and the owner stopped believing they'd ever find it again. Which would mean there has to be an awful lot of odd socks in Gensokyo...

Cirno is in fact absurdly powerful
Cirno's power is defined as "Manipulation of Cold." She mainly uses it to make ice. But who's to say that's the only use of such a power. If she can manipulate Cold, then she can make things colder... or less colder, AKA heating things up by taking away the "cold" in it. She could also instantly reduce something to Absolute Zero. This destroying it in an instant. Or perhaps taking away so much cold that it burst into flame or even melts or just vaporizes. Sadly, Cirno's not smart enough to use her power in such creative ways. "Yuuka: (After raping Cirno with her hand) You lose. Cirno: (After impaling Yuka on an ice spike out of thin air) You lose more."
 * Kind of supported by the fact that Shikieiki judges Cirno to be a menace and thinks that she's a fairy with "a little" too much power.
 * The theory's also been put around that Cirno's ability to manipulate cold is just the only bit she's managed to understand of her true ability, the ability to manipulate matter at the atomic level, at which point she pretty much becomes Dr. Manhattan.
 * There's a fanfic (called "The Last Stand of Cirno the Valiant") about Cirno training to get stronger, getting closer to that point, but then the rest of the cast descended on her like a bomb. How would you feel when it looks like you'll be upstaged by a "weak ice fairy". On the bright side, she takes out Yuuka, who just lost the last bit of sanity she had.


 * Alternately, Cirno was once truly one of the strongest youkai in Gensokyo in the distant past. Due to various events, she was sealed into her current state, and will never give up stating that she's the strongest, as she refuses to accept her current status and sink into despair at being depowered into being merely the strongest fairy.
 * She was sealed along with Rumia, obviously.
 * A doujinshi along almost these exact lines: Cirno and Rumia were once among the mightiest of youkai, but both lost much of their powers and mental faculties fighting in Yukari's disastrous Lunar Invasion.
 * That doujinshi (Three Dark Times) also claimed that Yukari, Cirno and Rumia were the only three participants in the Lunar invasion, which doesn't seem too credible. Then again, this is fanon.
 * If she combines this power with Utsuho? Their combined ability will produce cold fusion.
 * That was terrible.
 * Cirno has seraphim wings, 6 wings usually mean quite a lot of power.
 * Does that makes her the reincarnation of Sariel considering the Good Makai route ending in HRtP?
 * This troper has another take on Cirno's power. According to me, Cirno DOES have the power to make something drop to Absolute Zero, thus killing anyone instantly, just like the original poster theorised. According to me, she IS able to use it. However, just like every other being in Gensokyo, she's forced to abide the Spellcard rule! Her skill in Danmaku is weaker than her skill at properly manipulating cold, and that misleads everyone into thinking she's weak. Her power is on par with the most powerful beings in Gensokyo, but just like them she can't use it, for such is the rule. If Marisa ever fought Cirno without Cirno playing by the danmaku rules, Marisa would freeze instantly, and then Cirno would make her shatter to pieces and laugh.
 * Further evidence, especially of the spellcard thing: Cirno has appeared five times. First two times she was one of the wimpiest bosses in the game. In her fourth appearance she's tied for third and fourth boss, though she's fighting against Aya at the peak of her author favoritism so nothing short of Yukari stands a chance. But in her third and fifth appearances, she appears as a playable character. In PoFV she's still an "early" boss but is capable of beating up a bunch of A-listers if you follow a non-canon story path, but in Hisoutensoku she's on the same level as, and has a storyline where she beats up Marisa, Alice, Utsuho, Sanae, and Hong Meiling. Looking at China, she was a pushover in EoSD too but can hold her own in Hisoutensoku as well; it has been stated in canon that she's good at martial arts but not at spellcard battles. Why this leveling of the playing field for those two? Because in IAMP, SWR and Hisoutensoku the characters are no longer following the spellcard system, but a hybrid of the spellcard system and real fighting. So Cirno and Hong Meiling get to stop playing their solely weakest suits and get massive boosts in power... which only makes sense if Cirno also had a great deal of power which she was unable to use in spellcard battles but can draw upon in SWR. If she was allowed to fight without spellcards altogether, she would probably be able to take anyone. And now there is Fairy Wars in which she is the only playable character...
 * Addendum: Meiling was a joke character in IAMP because she was out of practice—after all, it'd been a while since anyone in Gensokyo had fought with anything except spellcards and there's no reason to keep training at martial arts if it looks like you'll never get to use that again but desperately need to get better at spellcards. After IAMP it became clear that there was definitely still a chance of getting to use her martial arts again, so she started training again, so by Hisoutensoku she's at least not intentionally weaker than the rest of the cast. Also, in EoSD Cirno was significanlty weaker than China, but in Hisoutensoku they're on par and in fact Cirno's tentatively ranked higher than her. China's as much in her element in Hisoutensoku as we can ever expect to see her, but Cirno's still probably not—fairies aren't exactly known for their physical strength, and even though it's not (entirely) spellcards they're restricting themselves to formalized offensive spells of a sot rather than directly applying their powers to making the other person dead as fast as possible.
 * Also, don't forget that the entire cast of fighting games (And so Hisoutensoku) is composed of very high ranked characters.
 * Cirno should be able to use Ice-nine, no?
 * She could until Red Mage stole it (and used it to destroy a universe).
 * She still can create it, but she doesn't because if she froze all the water in the world, most people would die... then who would she reign upon when she finally decides to step out of the shadows?
 * Cirno doesn't "Manipulate Cold". That's Letty. Cirno's ability is "Manipulation of Cold AIR", according to Letty's interview.
 * Aya's material is not to be considered as very reliable. Nor are Letty's words, seeing as she is clearly annoyed by Cirno. Cirno and Letty have the same power, though one could consider Letty's to be greater, seeing as she is a youkai of winter (it is canon that she is not giving her best during that battle) and Cirno is a mere fairy. Cirno's power is clearly stated to be cold, and she can conjure up ice, which does not fit into "manipulation of cold air". She DOES however seem to control cold air among others, as evidenced by her Cold Tornado spellcard in 12.3.
 * Maybe she just has permanent brain freeze.

Cirno utilizes some form of Thermosynthesis
It's mentioned that the air around Cirno is always cold. Since "cold" is merely the abscence of heat, she logically could be "creating cold" by absorbing heat. If the absorbed heat then becomes fuel for her magic powers, this could explain Cirno's power fluctuations. The colder the air around her is already, the weaker she becomes, as there's less heat to absorb to fuel her power. She's at her weakest in Perfect Cherry Blossom, when it's deep winter (despite the fact that it shouldn't be). In Embodiment of Scarlet Devil, she's at the Misty Lake, which is probably chilled by her own power, what with her living there and all, and due to the high specific heat of water, once it's chilled, it will tend to stay chilled for a while, chilling the air around it (Which would create the namesake mist!). All this chilling... chills things a bit, keeping Cirno relatively weak (but not as much as in PCB). Now we get to Phantasmogoria of Flower View and Unthinkable Natural Law, where she's a playable character. Here, Cirno leaves the Misty Lake and roams around in warmer climes... and suddenly, she's on par with typical player characters like Reimu and company. And when she gets dumped in a Nuclear Furnace, she can go toe-to-toe with resident Nuke-Girl Utusho. It's pretty apparent that Cirno's power follows a general pattern of being inversely proportional to the temperature of the area around her.
 * Then why was her reaction to Okuu to run away screaming? Not to mention that she was complaining about the heat.
 * Well, just because the heat boosts her preformance, doesn't mean it wouldn't be uncomfortable, and a walking atomic bomb would probably be frightening regardless of how powerful you are, especially if you have a childish brain that's not so good at logic. Alternativley, Cirno may be unaware of this detail of her power, for as we all know, she's not all that bright, and she has probably been living in the cold environs of Misty Lake for most of her life. I'ts perfectly reasonable that she's clueless to the fact that heat makes her stronger.
 * Actually, it says in Perfect Memento in Strict Sense that she's actually weak to fire and objects that are too hot to touch, although that could just mean that she can feel pain from being burned, just as a human does, if not worse. In other words, unless she actually makes a conscious attempt to siphon off the energy from the flame, she'll end up hurting herself instead.
 * Cirno also gains power in her game by freezing bullets, and grazing, both of which can be construed as ways to leech energy off enemy attacks.
 * And she can't freeze fire bullets without a use of a bomb in her game, not to mention that lasers can shatter the ice in a way that can hurt Cirno...
 * Does that mean that Cirno would be the ultimate Magical Girl?

Flandre Scarlet is the daughter of Arcueid and Shiki
Besides the obvious similarities in physical appearance (and in a sense, personality), Flandre has the ability to destroy just about anything by taking its "eye" into her hand and crushing it, which sounds suspiciously like the Mystic Eyes of Death Perception. Of course, this means that Remillia is not Flandre's real sister. Maybe that's why she's locked in the basement.
 * Related to the above: I've seen a fanart on pooshlmer of Flandre and Remilia's with their parents. Who? Arcueid and Alucard.
 * Flandre is 495 or so years old; humans don't live that long. Flandre's power is more related to Kira Yoshikage's Killer Queen stand than anything in Type-Moon.
 * I know. I was thinking time travel would have to be involved for this to be true. Yes, time travel is impossible in Type-Moon, I don't care.
 * Miss Blue, user of the Fifth True Magic ("Manipulation of the concept of time, allowing true time travel") would like a word with you, as would the Holy Grail (pre-corruption).
 * Still seems a bit nonsensical, on that note, there is quite a bit of Flandre and Noriaki Kakyoin fanart appearing, what's that all about?

Sakuya is a Lunarian.
Her themesong is called "Lunar Clock ~ Luna Dial." Kaguya, a Lunarian, has the ability "manipulation of eternity", which is quite similar in effect to Sakuya's "manipulation of time." Also note that according to Eirin's profile, Eirin was "surprised" to see Sakuya during the events of Imperishable Night, and she doesn't seem to be concerned with her own mortality when Remilia brings up the subject after defeating Mokou—Lunarians are already immortal; nor does she seem concerned about the madness-inducing moonbeams, since presumably Lunarians are already immune (Marisa is "insane to begin with", it isn't mentioned in the Border Team's scenario, and Youmu does feel the effects).
 * Alternatively, Sakuya is Eirin. Due to an accident involving the Luna Dial, Eirin accidentally created a younger, amnesiac temporal double of herself, whom she quietly shipped to Earth's future (i.e. contemporary times) to avoid ... political problems. And then she made the Elixir for Kaguya and got actually exiled to Earth, oh well.
 * Or, Sakuya was created using Kaguya and Eirin's DNA. This explains all of the above, without the discrepancies included.
 * This editor still prefers the  theory in this case.
 * This editor feels  is a much more plausible explanation anyday.
 * Yeah... I'm not sure the  Theory makes much sense. Unless Eirin pads or Sakuya's bust size is real.
 * They're both washboards if we go by ZUN's art.
 * Another possibility; it is mentioned that the Lunarians used Earth as a prison/place of exile, which strongly implies that Kaguya and Eirin are not the first or only Lunarians to end up on Earth. So here's what I think: either Sakuya is such an exiled Lunarian, or one of her parents was. Especially the latter possibility would explain why Sakuya is commonly considered human in spite of having time-space manipulating powers that are far beyond what even modern human technology is capable of, and it would also neatly explain why she is in possession of a Luna Dial (which might even be some kind of secret or forbidden technology, and the fact that she, or her parent, acquired one could very well be the reason he/she got exiled to Earth in the first place).

Lunarians are genetically human.
First of all: the Border Team's ending states that for the purposes of the ongoing "Youkai must kidnap humans; humans must exterminate youkai" conflict, the Lunarians (apart from Reisen, presumably) are considered half-human. If there wasn't any "humanity" to them, why would they need to bring it up? Second of all, Cage in Lunatic Runagate mentions that Lunarians originated on Earth, and throughout that and Silent Sinner in Blue, they all (except Kaguya) make much of the fact that they are more "pure" than the people of Earth.
 * Akyu considers them human, and they were apparently telling people that they're human at the expo, so this is pretty likely.
 * This also dovetails with the above theory that Sakuya is a Lunarian.

Yumemi Okazaki will appear in Touhou 12
For those who haven't played it, Yumemi entered Gensokyo in something very much like a UFO way back when. Plus, there is a red cross on the status screen.
 * Agreed. The story of Unidentified Fantastic Object is also confirmed to be mirroring Phantasmagoria of Dim Dream: A strange object from the sky appears and girls race to reach the object first, except instead of Reimu, Marisa and a bunch of other girls (including Mima), this time it's just Reimu, Marisa and Sanae.
 * Jossed Though there is room for an argument for Chiyuri/Muramasa here.

Kisume is Wriggle's sister. Or at least a close relative.
The hair color could easily be coincidental, but: They both have a reputation for kicking/bucketing Marisa in the face. Kisume's the midboss to Yamame, a spider youkai - and spiders love insects. And then there's the fact that Kisume hides in a bucket: she could be hiding pants (and/or a glowing ass) like Wriggle's.
 * Spiders love insects because they're tasty; not exactly good relationship material. Granted, many good relationships in Gensokyo have a strong foundation of abuse.

Cirno is farsighted.
Why else would she have a huge blind spot right in front of her when she casts Icicle Fall Easy?
 * This troper always thought that that was her first spellcard ever, and, being rather childish, she always leads with it despite it being her weakest spellcard.
 * This troper has read a good theory on Youtube: Cirno uses this spellcard not because she's stupid, but because she's actually smart and expects, perfectly rationally, that no opponent would be idiotic enough to go and stand in front of her face. When she finds out she's wrong, it's too late...
 * This troper once saw a comic showing Cirno using Icicle Fall Lunatic (yes, it doesn't exist, just go with it). It created a giant iceberg in the shape of an icicle. Cirno then commented that she was scared of her own spell card.
 * Is there a link to the comic?

Touhou was imagined by all the British queens...
And Hitler, as he descended from a long lineage of them. Most of the setting reminds of some British/European cultural references. The Japanese folklore characters might have been added by Queen Victoria, and greater part of their cultural references was added by Hitler, that was in the same side as the Japanese in the WW 2, so, knowing a bit more about them. Elizabeth II herself just updated most of the mythos and reimagined the characters more moe than before, as she probably is secretly an anime fan. Unless William and/or Harry manage to declare their queen descendence, like Hitler, the Touhouverse might perish, as it needs the queen royalty to survive. It seems rather crazy, but sorta works.

Alice is a lich.
She is a magician who was once human, but is now a humanoid youkai. It is possible that she died, went to hell, and used her tremendous powers as a magician to restore herself back to life, although she was no longer human by the time she had done so.
 * Flesh regeneration really isn't that hard to manage. It's just most "outside" Liches are cursed by gods for accomplishing immortality. Skull faces are not pretty, and any god-like being in Gensokyo would sooner die then have anything not be pretty.
 * Well Kanako does mention that a smile is more effective in attracting believers than intimidating them with her powers.
 * Pff no wonder she was losing followers. * Get's back to the important work of sicing his creature on some poor hapless villagers* Let's see you not believe in me now heathens!
 * Not unless she went about turning into a youkai a really roundabout way. According to Perfect Memento In The Strict Sense, all you need is to learn a couple of spells that apparently aren't that difficult if you have ready access to magic books.
 * The series is rather schizophrenic about that. Marisa refuses to say whether she's capable of studying immortality or choosing not to; even when the context should bring it up. (Like when discussing the Hourai Elixir.) Also, Hermits seem to go through a lot of trouble for something "easy" for Magicians to do.
 * So if Alice is a lich, what does that imply about the contents of her locked book?

Sakuya is a close relative of Youmu.
Both Sakuya and Youmu have pale gray/white hair (most likely a recesive gene). Sakuya has time magic which could have been used to train Youmu to become super fast. Sakuya may have been the "oddball" of the family and not been able to learn swordsmanship or the family was divided into certain weapon sections. It is not clarified what Sakuya's real name is, so her last name could indeed be Konpaku. Maybe she was a vampire hunter and when defeated by Remilia she was hit in the head and had severe amnesia, never remembering her previous life. Youmu may have been young at this time so she didn't remember Sakuya causing the battle in PCB. Although Sakuya is estimated to be 16–20 years old she could be the half ghost half human hybrid like other members of the family. So judging on appearance doesn't work here because Youmu and Sakuya both appear to young, but Youmu is at most 60 years old. Youmu and Sakuya first appeared with red eyes (another recesive gene in the real world). Also, sorry if this was long.
 * Alright, so where's Sakuya's "Myon"? Surely you're not forgetting the most important distinguishing feature of a half-ghost.
 * The "myon" might have wandered off when Sakuya forgot about being a Konpaku.

The real reason Yukari's invasion of the Moon failed?
It was because Bugs Bunny led the moon rabbits.
 * With Sailor Moon and Arcueid Brunestud flanking.
 * Add in General Woundwort and this guy, with The Killer Bunny of Caerbannog as their secret biological weapon... then MAYBE it becomes plausible somewhat.
 * Reportedly, she did it to show the other youkai about how bad war could be. Just As Planned.

Aya isn't ZUN's girlfriend, but rather, his self-insert character.
It makes some amount of sense, if you think about it a little bit. First, there's the matching outfits (as well as the black hair and Nice Hat.) Secondly, Aya, being a tengu, loves to drink—and ZUN is well-known for being akin to a Drunken Master himself. Third, Aya's entire purpose is to collect interesting information on the ladies of Gensokyo, as well as photographs of their danmaku / spellcards; ZUN himself collects "information" in a sense in the supplemental materials, and creating the danmaku itself is pretty close to collecting pictures of it. Her tendency to be overpowered could be attributed to ZUN simply indulging in a little bit of Mary Sue-ism every once in a while, like most fanfiction authors occasionally do. (As for why Aya isn't male? Heck, when in Gensokyo, do as the youkai do.)

Yukari's first Lunar Invasion was actually a plot to eliminate the most powerful youkai of Gensokyo
Yukari's motivations behind her first lunar invasion have always remained a bit of a mystery, and popular theories postulate that she was either trying to take the riches of the Lunar Capital for herself, or that it was just her way of teaching the other youkai about the evils of war and imperialism. But what if there was something more sinister going on? It is not unthinkable that there were some very powerful youkai in Gensokyo back when Yukari came up with the whole idea - some of them may even have been so powerful that they rivalled Yukari herself. Or alternatively, they were just as old and experienced as Yukari and may have known her for a long time. They may even have known and understood Yukari a lot better than she was comfortable with (maybe they knew of an Old Shame, or maybe Yukari's a wee bit paranoid about people who might just figure out her schemes and intentions). My point is; what if there was a bunch of youkai in Gensokyo that were a potential or actual threat to her? If these youkai really did pose a serious threat to her, then it would make sense for Yukari to devise a plan to, well, get rid of them - a plan like, say, tricking them into invading the moon together, luring them into a hopeless battle against the Lunarians, and then closing the boundary between Gensokyo and the Lunar Capital before the others could retreat...

Shinki and Alice are...

 * Mother and daughter; Alice was actually created by Shinki, an "Artificial Child" if you will.
 * As a side note, since Shinki claims to have created everyone and everything in Makai, this would also make most or all of the other characters from Mystic Square her "daughters" in the same sense and Alice's sisters.
 * Foster mother and daughter: Alice fell down the metaphorical rabbit hole when she was young or a baby and was adopted by Shinki.
 * ABSOLUTELY NOTHING: Shinki and Makai were retconned out of existence.
 * The Makai still exists; no word on Shinki, though.
 * Renter and outsider. Alice was a human who had been training to magician-ship since childhood. Mid-training, she somehow found her way to Makai. Somehow, Shinki let Alice stay as long as she'd like.

Mima is...
So what about the fact that Mima and Marisa clearly exist at the same time? Well, Mima is often referred to as a ghost, but she herself insists that she isn't one (and, in fact, denies being dead at all), while ZUN more commonly calls her an evil spirit. There has already been some distinction made in the Touhou universe among various types of lost souls and similar phenomena; ghosts, phantoms, and evil spirits are all different things. It's also been stated in Silent Sinner in Blue that a vengeful spirit can divide itself without lessening or otherwise affecting the original, and that this is essentially a characteristic of spirits or souls. Who's to say some part of a person's essence couldn't move on to reincarnation while still leaving something behind? Mima herself is said to have been an evil spirit for a very long time, so much so that she doesn't remember much of her own evilness. It's likely that she's quite different from whoever or whatever she originally was.
 * Completely retconned out of existence.
 * Marisa's biological mother; this is somewhat implied by a music CD of ZUN's.
 * Marisa's teacher, and possibly a sort of "adoptive" mother.
 * The spirit of a member of the Hakurei family, possibly a branch member.
 * The goddess of the Hakurei shrine. She had been canonically referred to as like both spirit and diety.
 * The same soul as Marisa, from an earlier life. Bear with me for a moment here! Going from that same story snippet in a music CD that gives rise to the "Mima is Marisa's mother" theory, the reason people assume it to be about Mima is that the song it accompanies is one of her themes. But taken on its own, the story seems more to be implying the same thing as the title of the song states: Reincarnation.
 * This troper holds the idea that one of the duties of the Palace of Earth Spirits is the capture and punishment of (even self-proclaimed) evil spirits. The reason why Mima hasn't been around lately? She's in detention at Satori's!
 * ...making the Touhou games. Whenever Zun says he feels "forced" to do something, it's because Mima is forcing him.

Yukari is an Eldritch Abomination disguised as a human.
What else can you call something that spends most of its time residing between dimensions? As far as I've gathered, she goes outside normal spacetime when she teleports.

Yukari's gaps are connected to the Gate of Truth
In addition to the creepy eyes, her and they aren't hers, much like the titular Gate in FMA. Considering that a gate is just another boundary...

Shou is Pudge from DotA
She looks like being patched together from several other characters (the Ringband of Komachi, the hairstyle of Shizuha, the Hip of Yamame, the clothes of Reimu etc.) and can "attract" Treasure. Pudge does that using a meathook. Also Pudge can slay living stuff and patch it on himself.
 * Speaking about similarities, she's blond and has a spear, but she's not Valkyrie from HoN.

Another goddess will be introduced later.
She will represent herself with slugs, and will be revealed to have beaten Kanako in a fight in the past. If you don't know why, Jan-Ken-Bo, the Japanese version of Rock-Paper-Scissors, goes like this: Snake eats Frog, Slug melts Snake, and Frog eats Slug.

If Suwako ever fights Slug-Goddess, she will come out victorious in accordance with the theme.

A lot of characters can equal or outmatch Yukari's "Omnipotence".

 * 1) Remilia, she can manipulate fate, that means, she could theoretically decide what will happen. ANYTHING. She could decide, that Yukari would just relax and the next second * BAM* dead. And if someone is plotting up something against her, she could manipulate fate, that he will never succeced, or even better: Manipulate fate that no-one is standing up against her while conquering the very existence on cruise control.
 * 2) Kaguya, she can do pretty much the same thing than Remilia, but on a diffrent way. Her ability allows her to let stuff last eternal (aka. Time Stands Still) or she can cause things to happen at an instant. The theory of Singularity says, everything happens somewhen, you just have to wait enough. Kaguya doesn't have to wait.
 * 3) Ex-Keine. Being able to alter History is pretty badass, but History isn't just past, it's also FUTURE! That means, Keine is ridiculously powerful, since it's basiclly the Ability of Remilia, with the bonus that she can alter things that already happened. (You say that she can do that only while Fullmoon? She changes History, so that there is always fullmoon!)
 * 4) Hina, yes, she can apply every curse on someone she wants. This implies eg. "Imperius" of Harry Potter. A curse which causes the cursed person to lose it's will and that person will only do the bidding of the one, who layed the curse upon it (in this case Hina). So she has omnipotence by forcing another Omnipotent being to do what she wants.
 * Yeah, cause the Imperius has never been resisted, and certainly not by a half-trained human teenager before... I don't think it'd work on Omnipotents.
 * As pointed out further down the page, Yuugi, who was explicitly holding back the only time we've seen her to now, has the "Power to control supernatural phenomena". That may mean she can just say "Oh, you want to alter my fate/rewrite my history/will me out of existence? Well I say that's not going to happen. What now?" In the end, though, I think what we end up with is a high noon standoff—with all these godly reality-bending powers, whoever shoots first will win. This probably makes for some very paranoid people at the top of the power chain.
 * Don't forget Sanae, who can create miracles.
 * Except that the powers aren't absolute. If they were, practically every character would break the scale. Yukari couldn't gap to the moon, she had to wait for specific conditions. Satori can't read people's thoughts if they're too far away. Yuyuko can't kill people who are immortal, Cirno can't freeze the nuclear furnace, Remilia's skill is implied to be tied to name-fortunes, meaning Yukari would have to accept a new name to get fate-changed, and even then it's a general fate, not a "you die in two seconds from X" deal. It's plausible that abilities flat out fail if contested against a stronger being- Yukari saw through Keine's history-hiding and ignored Suika's gathering, for example. Finally, the only (I think) specific canonical instance of one ability going against another was the last phase of the Kaguya fight, where she tries to break the eternal night enchantment. If abilities were absolute, she'd just be able to manipulate eternity to break it instantly. Instead she has to distract the protagonists with a barrage and break it in bits while they're recovering.
 * Basically, Yukari is considered above the others because she's the only character who has used her abilities to more than the most basic degree, regularly, and has a wide-ranging ability to begin with. Remi, Keine and Yuugi would probably be in the same boat if their powers were shown to be as wide ranging.

ZUN is building up an actual game to game plot and has at least one future game planned out already.
Before the events of Mountain of Faith, the games could only be identified of their place in the timeline by which characters were around. This gets tossed out the window now, with Kanako coming to Gensokyo in 10, granting Utsuho her powers in 11, and the geyser from 11, a result of Utsuho going mad from her new power, blasted the eponymous Undefined Fantastic Object (actually a grain silo) out from underground and into the air, setting off the events of that game. In addition, more exploration of the Fantastic Racism between humans and Yokai in Gensokyo has emerged to the point of being a major plot point and the entire motivation of that game's final boss, who comes off more as "Gensokyo Gandhi" than "Threat". Add that to other subtle inclusions, such as the presence of the technologically advanced Kappa, now with their own living fusion reactor courtesy of Utsuho, and it seems that a much more wide scale and important conflict is being set up by ZUN then just "Go out and shoot at things until the problem goes away".
 * That or the opposite: the next standard shooter will see a character reset like Mountain of Faith did and start on something completely new, and we'll never hear about all this stuff again. Note that even though the first three Windows shooters don't appear to be connected, they actually were planned as a set together; ZUN has said that he wanted to make a game where the humans and youkai team up (Imperishable Night) but first needed to spend some time establishing familiar characters. So those three games can be seen as a sort of story arc. Now the "Moriya Shrine Conspiracy" arc has had three games... and after all, ZUN is the Touhou fandom's biggest troll.

One of the 12.x games will be a RTS
Well, the above WMG suggests that ZUN is planning for war in Gensoyko. Why not?
 * A war that involves "PC-98 Touhou" VS "Windows Touhou"? Or a three-way battle between "PC-98 Touhou" against "Pre-Mountain of Faith Touhou" (when stories tend to be standalone, and when Sakuya used to be a sub-heroine [she seriously is in danger of becoming the new Mima]) against "Post-Mountain of Faith Touhou" (up and coming), with Reimu and Marisa caught in the middle.
 * And then the Moon gets involved. Mima stomping the Hime sisters would be hilarious.
 * Or perhaps just Humans vs. Yokai, given Byakuren's arrival as something of "Gensokyo Gandhi", as that above WMG stated, or a leader for discriminated Yokai. Excellent Fan Fic fuel even if ZUN doesn't touch on this.
 * Given the high amount of factionalism (The Tengu, the Spiders, the SDM, Byakuren's Temple...), the petty egos, and high potential for large scale fueds, I'm almost surprised that a massive Youkai war hasn't erupted in Gensokyo.
 * And there are a number of known potential flashpoints too. To name a few; Kappa-Earth Spider, Byakuren-Hakurei and/or Kochiya, Kirisame-Margatroid, SDM-Eientei, Hakugyokurou, and/or Yakumo.
 * Alternate WMG: One of the 12.x games will be a FPS. I mean hey, we have to cover the bases here.
 * Nah, it'll be something like Dynasty Warriors with danmaku. Which would be pretty freaking awesome.
 * 12.8 was just announced with the title "Great Fairy Wars," which stars Cirno and is based on the Strange and Bright Nature Deity setting.

ZUN is trolling the PC-98 fanbase.
In Touhou 12 there are so many Shout Outs to the PC-98 games, and yet NOT ONE PC-98 CHARACTER APPEARS! Seriously, he's doing this stuff on purpose. And we can't do anything about it. "Q: What's happened to the older characters? Like Alice, Yuka-san, and Mima-sama... ZUN: Well, it would be a huge pain to try to bring in older characters all the time. They'd show up, and everyone would be, "Where have you been all this time!?" It'd be weird to fit them into the story. And, I'd rather make new characters. Of course, I won't say they'll never show up again... So that means that he's not intentionally trolling the fanbase -- he's simply going with whatever's most plausible for the storyline."
 * When combined with the above theories, however, it works out to more hopeful conclusions. Or ZUN is having a Writer Revolt and honestly doesn't want to go back to his old work for reasons that no doubt will eventually be speculated at and become WMGs of their own, slipping in tantalizing references either as subtle Player Punches or as a way of rewarding the old fans with easter eggs and references..
 * References is the wrong word. The most recent charaters are Ripoffs from existing characters such as Nue is Flandre, Murasa is Chiyuri, and Byakuren is Mima.
 * But Flandre isn't from PC-98... Also, Byakuren is more of Shinki. And then, Shou originated from Makai. Hm...
 * On the other hand, Kogasa fits as an Expy of Kana Anaberal (they both fail to scare their intended targets).
 * If I may redirect your attention to this:


 * The question is flawed. Alice? She lived on in Alice Margatroid!
 * The question is quite obviously from before Perfect Cherry Blossom. Yuka came back with virtually no alterations at all, the only one from the question that HASN'T showed up is Mima. This troper simply thinks ZUN is saving her for a special occasion, given how he seems to be aware of fan trends like Yukkuris, the China jokes, and so on, there's no way he's unaware of how people want her back.

The PC-98 characters will return via Time Travel.
That solves the "where have they been all this time" problem, doesn't it?

Byakuren is Shinki's form outside of Makai
See the similarities of the both. Byakuren even uses the same attack patterns as Shinki. Also, she brought one of her children again. And Myouren is a twisted Memory of her, which is in fact Alice Margatroid who was taken out of Makai by Force.
 * Byakuren was once a real human. When she was persecuted after secretly rescuing some youkai and sealed in the Underground, at some point, she made very good friends with Shinki and allowed her to use her identity. When Byakuran finally died, she gave Shinki all her memories and suchlike, so that Shinki could use her identity when travelling outside the Makai.

ZUN has only short-term memory
Maybe he is making up all those new characters since he cannot remember all PC-98 works properly?
 * The games aren't that long.
 * After all the series is 13 years old right now.

Reimu is totally inept in fighting, and wins only through cheating.
In the shooting games (where you can clearly see a spell-card based duel), Reimu has never, ever lost, for being able to rig the competition into her inevitable victory. However, in the fighters (where you clearly see that the combat is real), she hasn't won even a single battle in canon, and is the Rock bottom of the matchup table in SWR.
 * Well, nobody wants to attack her at full power due to fears that her defeat might trigger the Hakurei border's collapse, placing Gensokyo back in Japan. Nobody wants this, except possibly Sanae.
 * Nobody isn't correct - Cirno, Rumia, Mystia or similarly stupid characters might not even know that part about the Hakurei barrier. Flandre might even "accidently" kill her.

VIVIT is a Cyborg combined of Marisa and Ruukoto
In order to live along with Alice, Marisa had to find a way, to live as long as her. And since of her easygoing and careless nature, she wasn't able to use the anti-aging spell Patchy and Alice used, since it needs far more discipline than Marisa has. So she went with her burglar-nature and stole Ruukoto from the Hakurei Shrine. Afterwards she needed someone competent to fuse her and Ruukoto together. So she went with Rinnosuke and Nitori, because Rinnosuke has a good quantity of spare parts and tools, and Nitori possesses the know-how to do so. But this was a mistake. Somehow Flandre got informed of this project and during a party at SDM she informed Keine how much this insults human life and how humanity could be artificially enslaved with that. Therefore Keine erased the Knowledge of Marisa, Rinnosuke and Nitori. Marisa was told that she was VIVIT, a robot maid and Rinnosuke was told he would be Erich, an engineer in robotics. That opened the doors for Flandre's Plan to disguise herself as Marisa to get free of the SDM basement. VIVIT's enhanced optics demasked Flan-Marisa and so in Seihou her memory comes back, and she is taking revenge on her, for stealing her life.
 * I disagree with the beginning at least, because Mari's nature is not easygoing and careless. She's in fact one of the hardest workers in Gensokyo, which has allowed her to become a powerful witch even if she is a human of human blood (as opposed to her immensely gifted, horribly lazy rival Reimu). If Marisa wants to master a spell, as long as it's within her field of competence she will do it. About her stealing people's spellcards: this is a must for her, since she has no powers of her own, therefore must resort to spells developed by others. I can however guarantee you it took her lots and lots of hard work to get that Master Spark right. Somehow it seems to me there's more to it than the 4 simple steps she describes.

Cirno is a fan of The Beatles.
The Beatles: Rock Band and the entire remastered Beatles catalogue will both be released on 9/9/09, the strongest day ever. This can't have been a coincidence.
 * Or, much more likely, The Beatles are fans of Cirno.
 * Hm, is that what "kaleidoscope eyes" and "diamonds" meant?
 * Maybe Cirno copied that floppy.

Komachi is really a Bleach shinigami
As such she could Bankai; the reason why her Zanpakutou is a scythe instead of a sword is that her's is like Ichigo's and Kenpachi's in that its always in shikai state. Also, she's closely related enough to Matsumoto Rangiku which would explain her lazyness and nice chest(as frequently portrayed).
 * But she says in game that she can see lifespans, just like Death Note shinigami! She even refers to the eye deal!
 * That's because she's the ultimate shinigami; the Soul Queen. She is the target of Bleach's Big Bad. It's also why she always slacks off; she's just not used to work. And it's also the reason Shiki doesn't fire her; she doesn't have the authority, although she can still lecture her. Finally, it's why she is so strong, strong enough to defeat Tenshi in Scarlet Weather Rhapsody.

The Touhous are substantially less powerful than the games suggest.
This is my oft-trumped WMG, so I might as well plant this mutha here for safekeeping. The idea is this: all the characters' assorted useless-sounding superpowers, with the handful of really unspeakably stupidly powerful ones, work just as described and no further up or down the power scale. Danmaku is in fact a separate magical skill used to solve problems or blow off steam in a violent-feeling but non-violent fashion; skill at danmaku is independent of one's innate mystic powers. The 'Soak is not merely a place for monsters and such to hang out, but a sort of nature reserve to keep those too weird to live and too rare to die from getting steamrolled by superstition or the march of progress, as well as segregating the truly terrifying from a world where they would do the most bad. It is fortunate that so far all the big nasties have consented to fight using the harmless-but-flashy danmaku style, because otherwise all sorts of planetary holocausts could've gone down by now—Reimu is a tough little bitch, but that can only take her so far against an uncontrolled threat.
 * Reimu can still fly away from reality and watch as stuff passes through her while wiping her enemy out. She's still so broken.
 * Now. When you say "The Touhous" I read "A few of the Touhous". Suppose Danmaku was indeed harmless (and it's not, because no matter what you say, danmaku IS related to someone's mystic powers, Mokou throws fireballs, and Utsuho mini-stars!). Well, suppose it's harmless, for whom is it a disadvantage really? Rumia, with the power to make it dark? Lily White, with the power to announce spring? Flandre will still blow you up in one hit, and Remilia can manipulate fate with all the implications of it, and Sakuya can freeze time and beat you up, and Mokou is immortal, and Yuyuko can kill you with a thought, etc. Hell, even Cirno Baka has the power of "manipulation of cold". She chills you all the way up to absolute zero, you die, end of story. Basically, there's rather "a handful of useless superpowers" and "a lot of really powerful ones", not the other way around. You do have a point by saying, I quote, "It is fortunate that so far all the big nasties have consented to fight using the harmless-but-flashy danmaku style, because otherwise all sorts of planetary holocausts could've gone down by now". In fact Danmaku really has the objective to give mortals like Reimu and Marisa the ability to fight badasses like Flandre and Yuyuko without getting killed on the spot. But this is not a WMG anymore. It's frigging canon. It's in Perfect Memento.
 * Danmaku is almost certainly related to magical power in so far as some amount of the later is required to do it, but beyond a certain level it's probably more a matter of skill then power. Reimu and Marisa are quite likely so good at it because they you know do it all the time. Touhou characters do tend to have there powers exaggerated sometimes to the point of lunacy in fanon though, for all the talk of Yukari's supposed neigh omnipotence for instances she's never actually demonstrated many special talents besides creating a large magical barrier (WITH HELP) and teleporting. Certainly she's never shown the kind of casual reality warping omnipotence that the most outlandish and vague interpretation of the curt description of her powers could be stretched to include.
 * Don't forget that Reimu took down many powerful humans/youkais/whatevers (Marisa, Mima, Yuka, Shinki...) before the spellcard rule creation. Not only every not so powerful youkais but even stronger HAD to accept Reimu's rule to escape a pure and merciless annihilation. Reimu was just too lazy to hunt all youkais at once, so she made a rule to prevent an uncontrolled threat. Also before mentioning any flawless hax (boundaries, fate, death manipulation), think about Reimu being THE shrine maiden and how a godly power may protect her. I guess youkais had to think about pure skill/power to accept the rule.
 * Still, why was Utsuho obeying the rules? She can't destroy Gensokyo when she abides to the rules and she wouldn't fear that Gensokyo vanishes without Reimu, because that's what she wanted. Heck, why would anyone cause a ruckus then? Due to the spellcard rules (and to your theory, without them) not a single youkai could defeat Reimu.

Yuugi is at least as strong, if not stronger then Yukari.
Let's do a refresher here. Stage placement does not equate power (e.g. Chen, the Stage 2 boss AND the Extra mid-boss, due to being separated from Ran in the former causing her power to drop; also see Keine who was only trying to keep you away from the Human Village). She is part of the same group as Suika (who is one of the strongest in Gensokyo, according to Aya). 'Four Devas of the Mountains.' And, we all know she was only playing with us her sake NOT EVEN A DROP! She is more mature then Suika, in age (probably), and power (probably), and as such should be as strong (if not stronger.) Combined with her power being 'Power to control supernatural phenomena', it could possibly be the most dangerous (or useless) power in Gensokyo.
 * If dangerous she can use it to say... cause aliens to abduct someone? Bad example, but you get the idea.
 * If dangerous, she could negate all of the supernatural phenomena in Gensokyo. That's just about everything, by the way.
 * If useless, she probably could do something like... turn her water into sake? Another bad example, but you get it... hopefully.
 * Unlikely, as the main reason Suika is so powerful is her ability to manipulate density, which Yuugi doesn't have. Also, a good way to tell if someone was holding back or not is to look at their clothing after you beat them. If it's torn, they weren't. If it isn't, they were. Yuugi's is torn and her sake DOES drop, despite Memetic Mutation. That said, she is still significantly harder than any other Stage 3 boss in the entire series, and probably is the strongest in terms of sheer physical strength.
 * Everyone suffers Clothing Damage when they lose a battle, unless they are kicked off the screen, like most stage 1 bosses. That being said, most early stage bosses suffer from this, and stage 3+ bosses often say something after beating them. Plus, consider this interesting fact. Gensokyo is one giant super-natural phenomenon which could theoretically give Yuugi complete control over it. Youkai? Same. Shrine Maiden? Negate their spiritual powers.

Rating a Touhou character's power according to his/her stage is stupid.
This is made up from one thing: Sariel is the Final Boss of The Highly Responsive to Prayers, a Stage 20 Boss. If the power scaling goes up as expected (With EX-Bosses equaling Stage7 and Yukari equaling Stage8), she could singlehandedly destroy Gensokyo, the World and Chuck Norris.
 * We also shouldn't forget Yuuka Kazami in Lotus Land Story, now should we. She was the boss for both Stage 5 and Stage 6!
 * Combined with the above post, do I even have to say it?
 * Sariel is really a stage 4 boss. Stages in HRtP are divided into 4 levels, then a boss. I think.
 * Nope: There are four stages without a boss, and a boss stage after each of those sets. And because of the split route, there are six characters that would build the top tier: YuugenMagan, Mima, Kikuri, Elis, Sariel and Konngara. Also, I'd rather rate the character's power by their win ratio, as it would imply Yukari would be at zero percent, as battles done in teams are not legit for the ladder (bad luck for you, IN pairs). Reimu's and Marisa's wins in SA still count, as they only take a skill of the youkai with them, making those not participate in battles.
 * However, with a few exceptions (read on), rating an individual's level of power based on their stage is useful when ranking them against characters in that same game. EoSD is perhaps the best example of this, starting at "non even worth considering" threat youkai, continuing to more powerful beings then ending with the "OHSHI-" level power of Flandre. This method isn't completely reliable though, as among other things it implies Koishi is more powerful than Utsuho and Ran is more powerful than Yuyuko (the latter is possible, just very unlikely).
 * In SA the stage 4 boss is stronger than the following two. Also in Mystic Square, you can assume Sara to be one of the strongest in Makai (even though being a stage 1 boss). Because seriously, it wouldn't make sense to fight the gatekeeper last just because she is stronger than he others.
 * Koishi may not be more powerful than Utsuho (though she is very powerful), but she's definitely far more skilled than the birdbrain.

Yukari Yakumo is a troper
And is posting the entries that are trying to fool us into thinking our Touhous are less powerful than we know they are. Oh Yukari...don't ever change.
 * "Boundary of Sugar and Darth"
 * That would also explain all those Omnipotence Theories

Patchouli Knowledge is not an elemental witch, but a Warlock/Demonologist
Justifies both her demonic assistant Koakuma, and what she's doing inside a Vampire's mansion (people dealing with demons have always been outcasted from society, Gensokyo is probably no exception, and merely living on her own as an outcast was not an option for her, due to her poor health, and the fact that she could get lynched. So Patchouli naturally went for those who could accept her as she is, who happened to be Vampires.)

Touhou 13 will involve a REAL invasion from Makai
In the plot of Mystic Square, the Makai invasion was actually an influx of Makai tourists and vacationers, so it wasn't a real invasion. Now that that is out of the way, let me explain my theory.

1) Touhou 11 was caused by events in Touhou 10. Similarly, Touhou 12 was caused by events in Touhou 11. If ZUN continues, this pattern, than Touhou 13 will be caused by events of Touhou 12.

2) In Touhou 12.3, the fighting game, Reimu's victory dialogue with Yukari in Arcade/Versus has her states that it "Feels like the calm before the storm" This is after Touhou 12. Something big is going to happen.

3) Now think of Touhou 12 from the perspective of a Makai demon: A giant flying ship crash landed! Unidentified objects are flying around everywhere! A powerful being was unsealed! And finally there were sightings of a shrine maiden, a witch, and some green-haired girl during the whole thing, possibly the same ones that caused so much destruction to Makai and defeated our wonderful god when we were only trying to relax and explore a new world! Are they attacking Makai again? Are these the warning signs of a full scale invasion? We must make a pre-emptive attack before they do! We won't lose again!

And there's your plot for Touhou 13. (Alice and Shinki team up as the final boss!)
 * And somehow Mima will be the EX-Boss.
 * No Yuka would be the EX-boss. Mima would be Phantasm. XD

The UFO cast correspond to the Seven Gods of Fortune
. This is barely a WMG, since ZUN somehow managed to reference them with UFOs at the same time, but let's put it here for reference. Inspired by a fanart I can't find:
 * Hotei: Often seen in American Chinese restaurants, representing good health and abudance. Probably Kogasa Tatara.
 * Jurōjin: Associated with both longevity and wisdom. Due to his association with Fukurokuju, this is probably Nue Houjuu.
 * Fukurokuju: His name literally means happiness, wealth and longevity, (so he is often confused with Jurōjin). This is likely to be Byakuren Hijiri.
 * Bishamonten: Shou Tomamaru, obviously. Her appearence is even based on him.
 * Benzaiten: Goddess of art and beauty. Ichirin Kumoi is probably this, if only because Unzan is a different gender than anyone else.
 * Daikokuten: Associated with both wealth and mice, Nazrin is the perfect fit.
 * Ebisu:: Related to the sea, this is Minamitsu Murasa, ship captain.
 * Note that if you accept the similar SA theory above also, it meant that Satan released the Seven Gods of Fortune by accident. Talk about mixed metaphors!

Sakuya is a ghoul
One of the primary ways that vampires in the Old World of Darkness bind humans to them is by having them drink of their blood, making them their ghoul servants. Ghouls can live quite long through periodic drinking of their masters' blood and can attain a measure of superhuman physical ability. Plus, if a person or vampire drinks three times from the same vampire, he or she is Blood Bound to that vampire, which may explain why Sakuya is so undyingly loyal to Remilia.
 * This makes even more sense if you're talking about Vampire: The Requiem ghouls, which can learn certain disciplines.

The other two Devas of the Mountain will appear in future games.
Well, there's Suika in IAMP and Yuugi in SA... chances are the other two will pop up as bosses in the near future.
 * My bet's on them being Blue Oni since Suika and Yuugi are pretty clearly red.

Mokou and Kaguya symbolise the Sun and the Moon, respectively.
I'm not sure whether this is really a Wild Mass Guess or whether I'm just stating the obvious, because it does seem pretty obvious to me. The unending rivalry between Kaguya and Mokou is a symbol of the cycle of the Sun and the Moon. Fiery phoenix girl Mokou is the sun while shadow Lunatic princess Kaguya is the moon. As the Sun drives the Moon away during the day, only to disappear leaving the sky to the Moon at night, so does Mokou kill Kaguya, only to get killed by her later on, ad infinitum.

Mokou was given the power of a Phoenix by an actual Phoenix.
Popular Fanon, putting it down here. Unless it's an mutant ability, immortality usually doesn't grant door prizes. At some point in her immortal life; Mokou met an everliving phoenix that either wanted to die or was touched by her existence such that it gave its power to her. This would have burnt a mortal to cinder; but Mokou was able to absorb it. Nevertheless, this bleached her hair white. Which is rather impressive; given that the description of Hourai Elixir is that it renders every physical aspect of someone Eternal.

The PC-98 games and Windows games take place in different timelines that are connected somehow.
There's several rather significant differences between the settings and characters of the PC-98 games and the Windows games - the appearant absence of the Spellcard Rules in the PC-98 games, the fact that PC-98 Reimu rides Genji rather than flying by herself, Alice originallly being (or at least * looking* ) a lot younger than than Marisa and Reimu while she's implied to be a lot older than them in the Windows games, the presence of some high-tech weapons in the PC-98 games (Rika's tanks, Mimi-chan the ICBM) - but at the same time, there's also a few hints that the two settings/timelines are not completely separate continuities. One of the best arguments for this is the dialogue between Alice and Reimu in Perfect Cherry Blossom; Alice clearly reckognizes Reimu, and even asks her "Don't you remember me?" in a way that can only refer to their encounter in Mystic Square. Yet at the same time, Alice is - thanks to her backstory and mysterious age-up - * also* one of the best arguments for why the events of Mystic Square cannot have taken place in the timeline of the Windows games. The only logical explanation for this (other than this just being a mere Shout-Out, the Continuity Reboot being Lampshaded, or ZUN being drunk or not quite caring about the whole damn thing) is that the Alice from the Windows games timeline really is the same person as the Alice from the PC-98 games, but that she travelled from one timeline to the other at some point. The Reimu she meets in PCB is an alterganger, a counterpart from a parralel timeline/universe, of the Reimu that defeated her and Shinki. And exactly why did Alice travel to another timeline? My guess is that Shinki, being the loving (adoptive) mother she is, wanted to bring Alice to a safe place after her defeat at the hands of the protagonists of Mystic Square. So she created a portal to a timeline in which Gensokyo is a much safer place (thanks to the Spellcard rules, etc.) and, just to be on the safe side, she even went so far as to send Alice to a point in time before Reimu or Marisa were even born - hence Alice's mysterious age-up.

Marisa's supposed insanity...
Remember in Imperishable Night Marisa says she's immune to the full moon's madness effects because "she's already insane to begin with"? I think I might have discovered what she means... Marisa fuels her magic with "phantasmal mushrooms", right? Do you know what's a "magic mushroom" in real life? Marisa must probably consume a lot of those during her travels to keep her magic level high... Hence, she must be in a permanent state of... well... you know. Which is pretty much like temporary insanity. It's just a wonder how she manages to dodge all those bullets while being in such a state... Whoa man, I'm trippin' out man... WHOA! Shiny colors! Whoa man, that's really coo... OUCH! THEY HURT!
 * And her Master Spark is just the physical projection of her mind/what she has in mind. OMG RAINBOW POWER !

Youki Konpaku is ZUN!
It explains why he isn't in the games, and no one seems to know where he is. This also explains why ZUN is so thin In real life... he merged with his ghost half, to hide it. As for the hair... there is no official art for him, so Youki may have black hair. This leads to a problem though. 'How is he making these games?' Well, an above post said that Yukari is ZUN's drinking buddy, and tells stories from Gensokyo, and gives him Bunbunmaru news papers. That would explain it.

The next fighter will have Meira.
Surely there are more deserving characters from the PC-98 era to return. Well, that may be but Meira has a reason. She wants to steal Reimu's power, giving her perfect reason to return.
 * Arguably the same logic could apply to almost any PC-98 Touhou. Orange returned from training in the mountains and wants to test her new skills. Kotohime broke out of the palace again and is playing "cops and youkai" with all the new faces. Rika and/or Rikako have stolen Hisou Tensoku from the kappa. The Scarlet Sisters drank Kurumi's blood lake.

Reisen Udongein Inaba is actually a Lunarian, not a moon rabbit.
But she somehow ended up in trouble with the Lunar authorities, so she disguised herself and changed her name so as to blend in with the moon rabbits. Unfortunately, the disguise worked a little too well, and she was drafted into the Lunarian army with the others. Eirin has already seen through it, of course, but keeps her around so she can have a human to test on. Plus, look at her ears in her portraits in Touhou 8 and 9. Those black dots look suspiciously like buttons or fasteners...
 * Every moon rabbit in the army has those buttons, as far as I know. I think they are a sort of distinctive mark. I remember reading something like that on the Touhou Wiki.
 * Maybe they're all Lunarians disguised as moon rabbits...

"Half-Ghost" is actually a type of tsukumogami, except with ghosts instead of objects.
Let's take a look at the existing tsukumogamis in Touhou (going by literal appearance instead of conceptual): Now let's look at Youmu: she has a humanoid form, and is seen accompanied by a ghost. Obviously, at the very least, there's a similar principle at work here.
 * Medicine Melancholy (doll-tsukumogami) has a humanoid form, and is seen accompanied by a doll.
 * Kogasa Tatara (umbrella-tsukumogami) has a humanoid form, and is seen accompanied by an umbrella.

Zun never liked Mima in the first place
Fact: Mima was one of the most important recurring characters in the PC-98 games. Fact: Despite constant pleas from all the fans, Mima has not appeared in a single Windows game. Fact: The PC-98 games were created by a team of which Zun was a part, while the Windows game were all made by just Zun. Do I really need to explain this one? For whatever reason, Zun never would've brought Mima back for even a second appearance if the choice had been up to him, but it was not; it makes sense that now that he's producing works completely on his own he's not going to include elements or characters he doesn't like.
 * ZUN solely made the PC-98 games. Check the credits.

"Nue Houjuu" isn't her real name.
"Nue" is the name of her species, and the kanji for "Houjuu", as written, means "Sealed Beast," which is exactly what she was until immediately before the events of Undefined Fantastic Object. What do you think, boys and girls?
 * Satori is also named after her race.
 * Perhaps the names "Nue" and "Satori" are thought of as names for particularly exemplary members of their species, similar to how "Andrew," derived from a word that means "man," means "manly."
 * Nue indicates that she's exactly the same nue from the legend, and implies that she's one-of-a-kind. Thus, she wouldn't really need a name beyond "nue, the sealed beast".
 * Satori's a little trickier, but since satori are telepathic perhaps they have other ways of identifying amongst themselves and don't normally use names. Koishi likes to interact with youkai and humans outside her own species, so she named herself for their convenience, and Satori goes along with it.

Youkai still eat humans.
However, they're now considered a delicacy and the number of them eaten is very low. Perfect Memento mentions that Outsiders are eaten by youkai on sight or after they've lost interest on them. They may be fair game since it won't impact the resident human population. Also, they may have struck a deal where executed criminals are turned over to a youkai who wants to celebrate or something. "Suika: This is a hell raven. She's a humble bird that eats the corpses of the dead. Reimu: She must eat mostly fried meat, then. That'll be bad for her when she's older. Suika: But, it looks like she's eaten something pretty bad. Utsuho: What are you mumbling on about? Did you come on a trip here to get eaten? Suika: I can feel something that doesn't belong in hell. She's ... Probably eaten a god. Utsuho: See, your body's getting burned up pretty nicely now. I want to eat you up right now, but it's not good to rush. You have to let it fry just the right amount for it to taste the best."
 * Yukari eats humans by putting in them in one of her gaps.
 * Utsuho's another man-(and god)-eating heavyweight, as Reimu and Suika's Subterranean Animism scenario shows (some lines cut for brevity):


 * This considered, Rumia's probably one of the nicer humanitarians in the series, since she asked politely first.
 * Counterpoint: While youkai can eat humans, in Gensokyo it can generally lead to dramatically shortened lifespans. For one thing, there is the presence of Reimu, who has "youkai extermination" in her job description and is the main character. More importantly, however, is the idea that there are quite a few powerful youkai who live away from humans and want to be left alone and would not hesitate to put an insolent youkai in their place if they do anything to bring attention to them. Even Yukari, for all of her laziness, would be very quick to put an end to something that could threaten the peaceful stability of Gensokyo. If you don't believe, just ask Tenshi.
 * Not to mention, the humans of Gensokyo are mostly descended from youkai hunters, meaning that most of them have at least some degree of magical power. Thus, a run-of-the-mill weak youkai (bear in mind that even the Team 9 members are stronger than the average youkai) would be in for more of a challenge than you might think if they try to eat a human.

The Tails Doll is actually a creation of Alice Margatroid on a bad mushroom trip.
Less of a WMG and more of a fanfic, but I figured I'd post it here anyways, if it's not the right place, feel free to notify me. After the Great Shroom Incident, Alice actually made it a habit to look for these mushrooms and to eat them to take pleasure from the sensations they procur (not before locking herself inside her house so as to avoid trouble for Marisa and any others). Once, she had the bad idea of actually sewing a doll while being in such a state. It started as a Ran Yakumo doll, but as Alice, on that day, was having hallucinations about a blue hedgehog and his yellow two-tailed fox sidekick defeating a mad scientist, she decided to drop the Ran idea and to represent said sidekick instead, both Ran and him being foxes and all... Now Alice, even when tripping out of her mind, is a competent dollmaker, however her insane fantasies made her create something so weird that upon coming back to her senses and seeing what she had sewn, she screamed and threw the abomination out the window. However, her state also caused her to pour much more of her power into the doll than she did ordinarily: raw, chaotic, insane power. So, she threw the doll away, only to have it land square on Hong "China" Meiling's head. The angry gatekeeper was about to turn the doll into a punching ball, but then realized it might be more useful to another person... and it's so that Alice's creation became Flandre Scarlet's playmate, soaking in the little vampire's intense aura of immense power and insanity. After a few years, the doll born from Alice Margatroid's acid trip and fortified by Flan's magic acquired sentience as a youkai and phased itself out of Gensokyo and to another dimension, becoming known as the mighty Tails Doll, Stealer of Souls. Flan didn't miss it: she already had a new companion, a rather unsettling looking teddybear created by Alice on another mushroom trip. This teddybear would eventually acquire sentience too, and its immediate proximity to one of the most moe vampires ever would transform it into the creature known as Pedobear.
 * This WMG has singlehandedly made me more afraid of Flandre than all the innumerable "unstoppable murder machine" portrayals of her I've ever seen combined.

There are buses in Gensokyo.
Cirno said that "there are no buses in Gensokyo." Do you wanna really trust an idiot's word?
 * There's no need for buses in Gensokyo, since everyone flies. But Yukari could bring them in anyday.
 * true enough, even though we always see that Yukari brings train instead, anyway.

Umbrellas are a sign of power in Gensokyo
Yuka and Yukari always carry one around, and Remilia is often seen with one...See the pattern?
 * Kogasa is an umbrella, but her power by herself isn't very impressive.
 * Kogasa is clearly just holding back. She's the EX midboss, after all.
 * Kogasa also seems like the type to not care so much about silly things like danmaku when she could be busy scaring humans instead.

Touhou players don't play with pads because Sakuya will knife them.
It's not that they won't use pads, it's more like they can't.

ZUN will create a Mima Expy for Touhou 13.
Alright, so Byakuren's not quite an expy of Shinki (borrowing one spellcard? Jeez), but she's apparently close enough to piss off some fans. If ZUN did this for his own personal amusement, my guess is that for the next game he will create another character borrowing at least a few of Mima's spell patterns, to further enrage us and/or emphasize the point that Mima's not coming back.
 * Who would know, maybe he did it before, But we didn't know who.
 * Hell, We even have a New Youkai Moe~
 * If he did that, half the fans would just insist that it's Mima operating under an alias anyway.

Confirmed!!
 * By what, exactly? I don't see anyone who stands out as a Expy of Mima...
 * Soga no Tojiko. Fog Feet, somewhat similar outfit

Rinnosuke is actually Yuki Nagato.
Just look at his genderswap (ads in the link are NSFW). Which makes us think that there may be a Haruhi somewhere...
 * Yukari, obviously.
 * Alternatively, Rinnosuke is Kyon.

Sanae in Touhou 12 is really just Mima in disguise.
Here is the evidence. It also explains why she's so uncomfortable and powerful.

Sakuya is a Dhampyr
This would explain why she has both blue and red eyes. Blue eyes is when she is her "normal" mode. Red eyes is when she is using her more "vampiric" aspect, and thus fields a generally more powerful arsenal. Plus it may explain her young apperance, yet, if you go by Akyu's account, her behavior seems to be of someone far older than she appears. And if Sakuya is a Dhampyr, Remilia would have all the more reason to keep her around.
 * Plus if you want to go the Sakuya-was-a-former-vampire-hunter route, note what is frequently a Dhampyr's employment in that entry.
 * Clever, but there's one small problem - she can go 100% human in IN, while half-ghost Youmu can only go 50%.
 * If so, she must be Dio Brando's illegitimate daughter.
 * And considering that Dio is a massive asshole in Jojo canon, this gives Sakuya all the motivation she needs to be a vampire hunter.

Despite how she seems to act, Reimu's turned into a Blood Knight.
In both of her scenarios in Unidentified Fantastic Object, she acts like she's bigoted towards Youkai when she's talking to Byakuren, but we all know she's made friends with a good number of them. It's possible that she just wanted a good adrenaline rush, and thought that Byakuren would give her the challenge she needed, so she essentially trolled her into a conflict.
 * On the other hand, Reimu may have serious identity issues about being both the Hakurei Maiden as well as a growing girl, because her emotions may get in the way of some of the harder parts of her duty (although this may not be a problem at the moment in the currently peaceful Gensokyo). Danmaku play may be something she can really identify with herself, as her identity role while in danmaku combat is very simple. Therefore, she developed an addiction to danmaku play to escape from any possible conflicts between her life and her duty.
 * It should be noted that for all the Yokai Jesus or Martin Luther King jokes we make; Hijiri focused on peace for Yokai more than for humans. Marisa and Reimu mention that humans still need protecting; and that will result in conflict with Yokai.

== Reimu acts like a jerk to deliberately try and put distance between her and Youkai; as she's supposed to balance humanity and them. She is the Balance. (Yin Yang). She's failing, and is turning into a Youkai or possibly a Goddess/Celestial == She does view Yokai and humans equally; however, more yokai like her than humans do. She deliberately comes up with Super Dickery to try and distance them, but humans continue to avoid her, and the Yokai like her more and more (and she gains more and more of them as friends). Hijiri horrifies her because she sees this as her fate. Attempting to balance humans and yokai, but ultimately only have yokai are her friends and family. Not that this would be too horrifying, but it is a failure of her attempt at being Neutral.
 * This is why donations are so important to her. It's not the monetary value; it's the connection she has with the rest of humanity. Literally their investment in her. It's not Reimu's fault; btw. She is doing her best. But it is inevitable unless the human population in Gensokyo open up to her. (It's a two-way street.)
 * That doujinshi where she dies peacefully as an old woman with humans and yokai filling the shrine is possible future where she is successful.

Wriggle Nightbug was originally a boy
Gensokyo has some sort of Gender Bender-inducing field, and Wriggle wears pants because she only recently made the switch-over and hasn't adjusted. This also explains why there are so few males known of in Gensokyo—only those who can resist this effect remain male—the unconvincing Word of God that there are as many men, but they virtually never show up in-game just because is intended as a cover for this dark secret.

Gensokyo actually has a matriarchal society.
There are only four known males in the land, with the rest being insignificant characters who apparently spend all their time at home. Of the male characters, two are servants for female characters. one has mysteriously vanished without a trace, and one runs a shop that, despite a prime location, is inexplicably devoid of customers except a few "nuisances." Obviously, the males Stay in the Kitchen because that's what society expects of them—similarly for the men (well, turtle and cloud) who are servants to female characters. Rinnosuke decided to defy convention and try to open his own business, and has been ostracized for it... except for a few girls who are just too weird to care. As for Youki... perhaps he decided to remove himself from a society that didn't value him. Perhaps something more sinister happened. Perhaps it's entirely unrelated. Whatever the reason, he's gone now.
 * It's likely that something in Gensokyo's gene pool or magic field causes only women to gain magical powers, and therefore the men simply don't participate in the conflicts (i.e in the games) because they can't, due to magical ineptitude. They exist, they're just so unsignificant we don't see them. The exceptions being a FEW animal youkai, such as Genjii, and some elementals, like Unzan. Rinnosuke is one of the men who would normally not be seen in the games due to absense of powers and therefore of importance. He gets introduced in a book and from what I know, never does any fighting whatsoever.
 * I might as well post my theory on the subject: Most of the major (humanoid) youkai in Gensokyo are shapeshifters, who take Moe Moe girl forms to distract youkai hunters. This in turn leads to the humans assigning youkai hunting to the religious and to women, who are less easily swayed by feminine wiles. Thus, most of the characters we encounter (youkai hunters and youkai) are female, with menfolk in minor roles and behind the scenes.
 * If most hunters are female, shapeshifting into a moe girl holds no advantage while a cute boy might have advantages.
 * Genji remains male because he's a longtime ally of the Hakurei family and won't get hunted.
 * Rinnosuke is accepted by humans in his natural state and might not be able to shapeshift due to being only half youkai.
 * Unzan is too modest to shapeshift into a girl, hence his reliance on Ichirin.
 * Doesn't explain fairies, magicians, lunarians, gods, and other non-youkai also being entirely female. Or all of characters that are too powerful to be threatened by humans.

Hong Meiling is actually a human, not a youkai.

 * Although she's repeatedly described as a youkai, it's never been clear what sort of youkai she would be, and indeed, she seems more like Gensokyo's human population... except for the implication that she eats people. It's possible that she's just a cannibal, and people have assumed that she's a youkai because eating people is something they do—although not very often anymore. Following the Literary Agent Hypothesis, this faulty assumption would have trickled down to ZUN, who would repeat it.
 * Remember when she described herself as "just a normal person" in Embodiment of Scarlet Devil...
 * There's been some evidence that she's a Hong, or rainbow-dragon. While it's not exactly confirmed, the fact that her fighting style uses rainbows and her Chinese origin gives some evidence in favor that she is a Hong.
 * So what you're saying is Meiling is totally a dragon, right?

Humans can extend their lives by becoming youkai.
Perfect Memento states that a human who learns Shashoku magic, they become magicians. In Touhou, magicians are a subclass of youkai and enjoy the relatively longer lifespans other youkai do. If Marisa ever wanted to, she could learn this spell and extend her life.
 * Reimu, on the other hand, would have to perfect her border-related powers (maybe with some help from a symphathetic Yukari) and become a sukima or her divine powers and use it to extend her life or become a celestial.
 * Keep in mind, the magic words are "if they wanted to." Word of God states it's very easy for a Magician of some skill to "stop eating food" and become immortal. That Marisa hasn't implies it's a personal choice. Reimu's reaction to Byakuren also implies she'd possibly be opposed to the idea. Of course, if time keeps passing and the characters stay the same age, it may no longer be an issue.
 * Sanae may also be able to use her divinity to extend her life or become a goddess.
 * Given Suwako's dialogue with her in 12.3, she may well be a demigoddess already, and may almost ready to fully ascend.
 * Meiling's mastery of Chi could have made her a youkai. However, since this method relies on a person's spirit only, her abilities with danmaku, or magic in general, would be lower than the average youkai.
 * On the other hand, this would explain perfectly why Meiling is terrible at danmaku play.

Marisa is connected to Maribel Hearn and/or Yukari Yakumo
On the drama CD "Dolls in Pseudo Paradise", the character described in the story attached to "Reincarnation" is considered to be Mima, and her daughter is then Marisa. But Mima looks nothing like Marisa. Then who could it be? Why not look at the two people with uncanny resemblances. Descent from the human half of the youkai of boundaries would explain some of Marisa's potential.

Powers have an inverse effect on usefulness
By this of course, I mean that the more useful a power is by nature, the less potential it has. Consider Yuyuko's ability to inflict death. That's all it does. However, look at some of the more 'useless abilities.'
 * Reimu has the ability to float around in the sky. The results? Fantasy Heaven, where she floats out of existense and shoots at you.
 * This ultimately means that Reimu hasn't demonstrated her true ultimate power; the ability to eat sweets and not get fat, which if applied to combat would defeat entire pantheons of gods.
 * the above is already used in the form of Reimu having the smallest hitbox of the games she's in.
 * Yuuka has manipulation of flowers. This Troper once saw an eight panel comic showing Yuuka beating up Tenshi. When she found that her body couldn't be destroyed from the outside, she ripped of Tenshi's peach, took a bite, french kissed the seed inside her mouth... I think you see where I am going with this.
 * Through sheer focus, Youmu can slash at ridiculous speeds, create a body double, and is in decent spots on tier lists.
 * Of course, these only apply to the idea that the character has honed their power to the right degree. Yukari is still the strongest Youkai in Gensokyo, because she has totally mastered her power. Utsuho may have the most destructive power, but she doesn't really know how to use it, other then Beam Spam.
 * Point of contention: Yuyuko's ability is actually "manipulation of death", which while mainly manifesting as inflicting death also allows her absolute control over the dead. She just doesn't, because she's super nice.

Cirno is Satan
Specifically, Dante's version. Her symbol is a 9 in a circle. Fans take that to mean that she's an idiot, but it can easily be taken to mean the 9th Circle, the lowest point in Hell and Satan's location. What's more, Cirno is an ice fairy. Ice, as in the means of punishment for those in the 9th Circle. By calling the ⑨ an idiot in the Phantasmagoria of Flower View manual, ZUN wasn't just calling Cirno an idiot, he was calling Satan himself an idiot!
 * Holy frigging crap it all fits! That also justifies her false claims of being "THE strongest": Satan believes he is stronger then God whereas it's not actually so. Do want Devil Cirno as an extra boss!

There has only ever been one Hakurei Miko
Reimu is not the latest in a family of mikos to protect the boundary of Gensokyo, but is the first, last and only. While Yukari and the other youkai involved in its construction could contruct a boundary that would isolate Gensokyo from the world, they could not construct one that isolated the world from Gensokyo, preventing human access, and they determined that as they would be the focus for the former aspect a human was needed to be the focus for the latter (that humans still manage somehow to enter Gensokyo shows that this solution was not as perfect as they wanted). Who this "original" Reimu was and why she was chosen is something for another WMG, the point being that she became inextricably linked to the boundary, effectively giving her the immortality of the boundary as she cannot die while it remains and the boundary cannot fall while she lives. Without the option of increasing her own longevity (she still must age and die like a human, otherwise she wouldn't be human), Yukari used a variation of the "no reincarnation" state she placed on Yuyuko some centuries earlier, ensuring that at her death Reimu would insantly revert to the state of her original "sealing", a teenager with no memory of her past live/s, continuing the cycle.

Reimu is the Goddess of the Hakurei Shrine.
She even hints at it in Oriental Sacred Place. Specifically she's the Nameless, the Miko Goddess who was summoned by Watatsuki no Yorihime against Reimu. (Canon has shown you can summon a god against itself.) Reimu pretended to be puzzled on who that Miko was. She gets her Faith from the other side of the Barrier.
 * In canon, Reimu comments that she "doesn't know the name of the god of the Hakurei shrine." This is technically true; she doesn't have a deity name.
 * This is also why it's easy for her to summon other gods; being the concept of a miko; she's the god of summoning other gods.

The Spellcard Rules are a Reality Warp
Anyone in Gensokyo or neighboring realities like Makai must follow them when engaging in combat with someone. It doesn't even cross their minds not to. Even if they've never heard of Spellcards, they will be RetConed in.

The PC-98 Reimu and Marisa are the mothers or grandmothers of the Windows ones
The reason Reimu looks very different between the two is because she's a different person, just with the same name. Mima isn't around anymore because she lost interest after the Reimu she befriended died. None of Yuuka's old exploits are in PMitSS because she hasn't done that sort of thing for decades now, but Reimu (w) still knows what she's capable of because of stories passed down the family. Alice's first conversation with Reimu (w) is the result of Alice getting confused by the colour scheme and some family resemblance.
 * Embodiment of Scarlet Devil's manual said "Chronologically this title is not too far from the previous title, thus her age stays the same as before." so...

In order to enter Gensokyo, Kanako and Suwako completely erased themselves (and Sanae) from Outside World existence.
Even without faith, they would have existed in some non-corporeal form; at the very least through stories told by historians about what people used to believe. They may even have been able to have been "summonable" the way the Shinto Gods are in Silent Sinner in Blue. But they wanted to remain corporeal. So they took all the stories and records and memories that the Outer World had of them; and threw it into the Memory hole. Something that once existed in the Real World but then left a vacuum resulted in them appearing in Gensokyo; and not a single record of the Sky and Earth goddesses remain outside.
 * This is probably canon.
 * I'd sort of assumed they followed the Hakurei shrine example which IIRC exists on both sides, but is abandoned and run down in the outside world. So basically one day the shrine is suddenly empty and everyone is scratching their heads over where the teenage Miko living in it went.
 * Maybe they did force the barrier. And the result of ending up in Gesokyo caused the memories of their existence to vanish from the outside world. Chicken or the Egg.

The god that Utsuho ate was Blaze
It was a "fire"-ish being who granted its godlike powers to anyone who could defeat it and absorb them. Apparently Blaze won the tournament himself and ended up in Gensokyo, where he (possibly now a "she" if Gensokyo has a Gender Bender effect like the one in the Wriggle guess) lived out the rest of his life in Hell until Utsuho, on the prompting of Kanako, went down to absorb Blaze's power.

Touhou doujin is produced in Gensokyo
This was proposed in #tropers-touhou. Basically, Touhou doujin is the porn industry of Gensokyo: Patchu writes them, Koishi makes them happen, Aya takes the pictures, and Keine erases the history/evidence. Then, Kaguya uploads them to the Internet. The black-and-white manga style comes from a combination of data loss when the upload crosses the border and the fact that everyone in Gensokyo really looks Super-Deformed.

Maribel is a young Yukari.
Maribel and Yukari aren't dreaming that they are each other, they actually are, in different stages of their life. Yukari was born as Maribel, a human, and developed her ability to see borders until she could manipulate them as well. She and Renko entered Gensokyo and had many excellent adventures. But it wasn't the Gensokyo we know and love, it was the Gensokyo of the past, when the border was still young. Renko trained as a shrine maiden and Maribel eventually became powerful enough to become a youkai. After settling down in Gensokyo, the two had a falling out, perhaps over Maribel's becoming a youkai, and this is why they built their houses in different places, but both along the edge of Gensokyo so that they could keep an eye on the border / get luxury items from the outside / help humans coming across like themselves. Renko had children and fathered the Hakurei line. At the end of her natural life, Renko was reconciled with Maribel, and Maribel agreed to protect Renko's daughters and their descendents.
 * Alternative storyline: Maribel and Renko have their adventures in the present/future as Maribel's powers develop, but at some point Maribel goes to the past and becomes Yukari as we know her (Renko's fate is unknown).

Maribel is the reincarnation of Yukari
First off, it's very unlikely that they're the same person dreaming of being each other as in the common theory; Maribel spends most of her dreams running away from youkai and her tendency to bring back various objects implies that she's physically transported.

Maribel lives in what's clearly the future, and magic appears to be common knowledge when she lives. Sanae seems to come from the present day, and her move to Gensoukyou was due to people not having faith. It seemd likely that Maribel doesn't just live in our future, but in the rest of the series' future as well. Plenty of time for Yukari to die.
 * Yukari has lived for thousands of years. For what we know, she CANNOT die.
 * She can manipulate the boundary of life and death. So she can die, she'd just have to want to.

Eirin is genetically modifying Reisen.
In Cage in Lunatic Runagate, Kaguya muses on how "Udonge"; Eirin's nickname for Reisen is also the name of a lunar plant that becomes jewelled when exposed to "impurity". (IE, Earth) She considers that Eirin is trying to see if Reisen can become something greater than what she was on the sterile moon. The "Punishment Time" that takes several days of Reisen being unconcious is Eirin modifying Reisen's body so that it adapts to Earth. Normally, Lunarian's have a magical shield against "impurities" like disease and bacteria (No War of the Worlds type Deus Ex Machina, no.); but long-term exposure gets past the defenses. The immortals gained immunity to Earth diseases the hard way, but Reisen doesn't have that option.
 * Why? Well, first, it IS to keep Udonge alive. But Eiren has another goal. Now, consider, Lunarians are incredibly long-lived; but still mortal. Silent Sinner In Blue has them having an almost skeletal society; despite having a powerful one half a century ago. We only see the Watatsuki sisters and two guards as humanoid Lunarians in the entire city; (There's likely others, but probably not many) the rest being moon rabbits. The zealous pursuit of purity has resulted in cultural suicide; the lesser moon rabbits ironically enough not sharing this fate. Eirin foresaw this happening; and has decided to see if she can create a treatment to allow the most prolific of the Moon culture; the moon rabbits; to live on Earth. Sometime in the next couple of centuries (Eirin is patient), the population crisis will come to a head; with Moon Rabbits outnumbering human Lunarians to the point that they cannot be the dominant caste. Eirin will offer to take some of the Lunar Rabbits off their hands. Should the population crisis continue, Eirin will offer the treatment to any Lunarian who wishes to move to Earth. (Provided they accept Eirin and Kaguya's existence as is, of course.)

Yukari's Second Invasion of the Moon was a social attack.
Yukari, like Eirin, isn't just The Chessmaster; she's an immortal chessmaster. Moves that she makes aren't always apparent until centuries down the line. It was very important for the Moon Rabbits to sense that Reimu was summoning the Shinto Gods. This served as a distraction and gave the Watatsuki sisters a motive for not immediately killing or banishing Reimu; they needed to show Reimu to the Moon Rabbits to show that they weren't the ones unauthorizedly summoning gods. Something only they could do up to know. Now, Reimu and the Watatsuki sisters may be Nay Theist. they summon gods but they sure don't seem to worship them, but the Moon Rabbits are religious. And now, it's been revealed that those "inferior" Earthlings are capable of being conduits to the gods. This will have incredible impact on the Moon society years down the line, and severely take away one of the unique traits the Moon royalty used as a symbol of superiority.

The Lunarians are Lunarians
At the end of Final Fantasy IV the Red Moon, and all the Lunarians aboard, left the Blue Planet in search of a planet that was ready for them. Eventually they happened upon the planet Earth according to Touhou, complete with a seperate realm full of empowered humans, youkai, etc. The Lunarians decided that this planet was ready for them and stayed. This also means that the lunar rabbits are the current form of the Hummingway species, who were shown to be quite rabbitlike in Final Fantasy IV DS and Final Fantasy IV: The After Years.

ZUN has only learned how to draw males relatively recently
ZUN has always drawn everything for the Touhou series himself, even though ZUN isn't exactly the best artist ever. This seems to suggest that ZUN takes a certain amount of pride in drawing everything himself. Since he seems to have an obsession with creating female characters, it's not that huge of a stretch to suggest that at least during the PC-98 era ZUN simply had no clue how to draw a character that looked male. Instead of getting someone else to do the art, however, ZUN decided that since he liked to design female characters anyway, he should just make the cast be all-female. Notice that before Rinnosuke, none of the male characters were even remotely humanoid.

This all changed during the Windows era, when ZUN decided that he might as well try to draw male characters for once. Wriggle Nightbug was practice for him, as even though she was a female character she has feature usually associated with male characters, and is one of the first touhou characters to wear pants. ZUN couldn't draw a guy character in a dress, now could he? Rinnosuke is the result of his practice, but now that the tradition of Touhou having only female spellcasters has been established, it's doubtful ZUN will ever get to draw more males.
 * ZUN has never drawn Rinnosuke. He only appears in a manga he hired another artist for.

Parsee is part Tengu
She has the same ears as Aya. This isn't a weird coincidence, but a sign of mixed ancestry on her part. When the Oni moved to hell a few of the Tengu decided to come with them. One of them fell in love with a Bridge Princess, and Parsee is the result. This even explains her weird name; Tengu have traditional Japanese names, and we don't know about Bridge Princesses. She has her father's family name and her mother gave her a name from her culture. While her species is given as 'Bridge Princess', that is simply the side she primarily took after.

Parsee is a former human/near human youkai, like Alice.
Per the story of the Hashihime, her grudge against an unfaithful husband caused her to become a jealousy-ridden youkai. Her pointy ears are fakes, which she wears out of jealousy for the more unusual-looking youkai.
 * Being a Persian plays into this; her marital strife stemmed from culture clash with her presumably-Japanese husband. Her jealousy that other people can travel freely is because she's homesick for her homeland.

Meiling's reputation for sleeping on the job is Reimu's fault
During the actual game Meiling is never actually caught sleeping. She proactively attacks you before you even get to the mansion and attacks you again at what is probably the front gate. Assuming Remilia did the vampire thing of being active mainly at night, Meiling's job would be to keep out intruders during the day when her mistress was most vulnerable. She would then sleep at night. After Reimu beat Remilia, Remilia starts taking an interest in things outside the mansion and becomes more active during the day. With her mistress spending more time awake during the day, Meiling would have to stand guard at night as well as through the day; to guard her mistress while she slept and to guard the mansion when Remilia and sometimes Sakuya were absent. Meiling probably had to switch to that sleep system where you nap throughout the day to make up for not being able to get eight straight hours.
 * Going along with this, her story mode in Unthinkable Natural Law  might be her crashing from not getting enough sleep and all the REM sleep she missed giving her some really messed up dreams.

Mokou and Kaguya have a noble women's agreement to tone down their feud in front of friends and family.
Even in the most viscous interpretation of their continuous killing of each other; Mokou never harms the mortals in Eientei. Kaguya tries to avoid Keine as well; but Keine tends to butt in anyways. Hence Kaguya getting other people to do it for her in the Trials of Guts.
 * Despite her burning passion hatred of Kaguya, Mokou is actually on rather good terms with Eientei's inhabitants and doesn't associate them with her grudge. There is nothing to indicate that Kaguya possesses a similar opinion though, and indeed Mokou could easily have become a hermit to avoid anyone becoming a target of Kaguya (or even they already did and Mokou is attempting to avoid it occuring again).
 * The point is, whenever people see them together; they seem rather relaxed despite being Immortal Enemies. This is because other people are there. When they're alone; and nobody else can get involved; that's when the mutual killing starts.

Hatate Himekaidou will be one of the Touhou 13 Bosses.
Because it happened to Aya, right?
 * Hataters gonna Hatate
 * Kinda makes sense given what's known at this point. Holy spirits. Spirit photography.

Touhou 13 will be another Phantasmagoria Game
Because Phantasmagoria of Flower View came after three games, so now that another three games have passed, it seems fitting.
 * Dubious. ZUN has to know that nobody really likes the Phantasmagoria games.
 * That might just encourage him.
 * Nope. Regular shooter

Cirno is the forger of the Idiot Ball.
Cirno used to be one of the smartest beings in any dimension. So smart she was, that she discovered the secret of stupidity. All excited by the revelation, she created a powerful weapon using her newfound knowledge... a simple crystal orb emitting a strong mind flaying aura that immediately drops the IQ of anyone to come in contact with it. It would be called the Idiot Ball... Sadly, the creation of the Ball did not come without a price... prolonged contact irreversibly ruined the genius Cirno's mind, turning her into what she is now. The secret of stupidity was sadly lost along with Cirno's intellect.
 * Then how did Mermaid man get his paws on it?

ZUN really wants permission to include Jojo characters as partners to the protagonists in a game.
He has fitted countless references to the manga series in the games, modelled numerous characters after some of them, i.e Sakuya, Youmu, Yuugi, and even has dialogue almost directly quote the series "How many breads have you eaten?" (Remilia: Marisa scenario). Hell even some spellcards reference objects from the series (Red Stone of Asia: Kaguya in StB). Perhaps ZUN really is just waiting for the chance to include his favourite characters, pair them with touhous with similar powers, Sakuya/Dio/Jotaro, Flandre/Kira, Giorno/Yuka/Wriggle/The Moriya Trio, Youmu/Polnareff, and just smack the fanbase with a massive 180 on his all women law.

Kogasa will be a midboss in some future game, though not 13.
Why? Because who would expect her? Besides, Cirno did it, and she didn't have the fourth-wall breaking excuse.
 * She's a midboss in 13.

Alice Margatroid is a Doll.
PC-98 and windows are about 1 (one) year away from each other. What happened, is that this doll, called Alice Margatroid, is a reflection of what Alice could have been if she grew up, but since she opened the Grimoire, that won't happen. And Shinki's power is unknown, so the whole "Warping Alice to another Dimension" WMG above is possible, however unlikely, since her power has something to do with Sara, Luize, Yuki, Mai and Yumeko, since it was established, that everyone (excluding Alice) was created by Shinki. So unless she has an incredibly vague power like Yukari's Manipulation of Boundaries, it's safe to assume that Shinki's power is to give life. With that, we move to the Alice is a Doll Theory In Alice's description in Perfect Memento in a Strict Sense, She has blond hair and pale skin, and looks very much like a doll herself. Which supports the theory on it's own. But there is more to support this claim, this trouper has more evidence. But wait, the author of Perfect Memento also says that this Alice was once human, who became a Youkai. However, which Alice is she talking about? Is it Alice Margatroid? She's a doll though. So to be a moving doll, who is her puppetmaster? That would be Alice from PC-98. Which then links to the Momento, "She's the type of magician that was originally human and became one through training." This can be assumed when Alice first opened the Grimoire of Alice This makes two Alices in the same world. One who is the PC-98 Alice, and one who is the Windows Alice. Here, if Alice of PC-98 is controlling the Windows/Alice, then she would remember losing to Reimu and Marisa is Mystic Square. Therefore, out for revenge in Perfect Cherry Blossom. In Imperishable Night, it's seen in the prologue that W/Alice's dolls are capable of talking. If W/Alice can do it, so can PC/Alice, since with the Grimoire at hand, Alice has access to many spells. But W/Alice has a Grimoire too. Maybe the W/Alice has a fake grimoire, only to look like PC/Alice. So PC/Alice has the real Grimoire, and W/Alice has a fake. Which also explains why W/Alice hasn't used her Grimoire yet. It's because it's fake. With this theory, it answers why Alice suddenly came back all grown up, why she never uses her Grimoire, why she is described to look like a doll, and why Reimu didn't recognize her when she first saw her. W/Alice Margatroid is a doll being controlled by PC/Alice.
 * Or rather, Windows Alice is an Autonomous Doll made by the PC-98 Alice, and thrown to Gensokyo without any memories of her creation. The process made Windows Alice's inner subconciousness want to make an autonomous doll too. As said above, the Grimoire is fake. The figment of memory of Reimu and Marisa is adopted by the magic flowing from PC-98 Alice. (or Alice has seen them sometime before.)

Most of the bosses in Embodiment of the Scarlet Devil are expys of Negima characters.

 * Patchouli Knowledge = Yue Ayase
 * Sakuya Izayoi = Chachamaru Rakuso
 * Flandre Scarlet = Evangeline (Battle mode)
 * Remilia Scarlet = Evangeline (School mode)/ Ako Izumi (She was one of Eva's victims in volume 3, and she has a similar appearance to Remilia)
 * Hong Meiling = Asuna
 * Cirno = Remaining "Baka Rangers" (Rather, the idea of them)
 * I thought EoSD came out BEFORE Negima...
 * "Is that so~" Oh well. It was a fun WMG.
 * It's commonly believed Yue is a Patchouli Expy. So it's the other way around.

The Master Spark is powered by shipping.
This is why Marisa is paired up with so many people.
 * It's powered by love... that is sucked out of the universe a little bit at a time
 * All right, who HASN'T Marisa stolen from?

Okay, two theories on Meiling:

#1: Meiling does not actually sleep on the job.
She's actually in a state of hypersensitivity, in which she can discern threats more easily. The reason she lets Marisa through is because she doesn't feel that Marisa is going to be an actual threat to the mansion. And she doesn't regard Sakuya as a threat because Sakuya is a resident of the mansion and therefore belongs there. Sakuya only perceives that China is asleep and therefore gets pissed off about it. After all, why would Remi want a useless guard? She obviously sees something in Meiling.

#2: Sakuya never liked Meiling and gave her a form of brain damage.
All as an excuse to whale on her. One knight, while China was asleep, Sakuya sneaks up on her and stabs her in the head. Meiling gets screwed up by this and is never right again. She starts constantly falling asleep while doing her job, and who constantly checks up on her? Sakuya. This means that Sakuya gets to mistreat Meiling for failing to do her duties, and she enjoys it all too much.

Reimu is not underaged!
Time line recap PC-98 and Windows have a 1 year gap from each other. Gensokyo moves about as quickly as our real life. Which means during from Summer and Winter Comiket (And not Retisai) one year passes. Reimu begins Touhou 1 as a twelve(12) year old. This is very evidant in TH2. Those two game passes, and she is now Thirteen. TH3 and TH4 pass, she is now Fourteen. TH5 passes, and there there is a one year timeskip. Reimu is 15 and a half by this time. It is now Summer and EoSD takes place, and TH7 takes place. She is 16 by IaMP. Going to TH8 and TH9, TH9.5, she is now 17. TH10, and TH11 pass, she is now 18. TH12 comes out during the summer, and there wasn't a touhou game for 2009 Winter Comiket. Reimu is now 19.
 * ZUN specifically says that the timeline is wonky, and encourages fans to disregard it.

Nazrin is a Planeswalker
As you can clearly see, at some point there was an Ondu Relic Hunter named Javad Nasrin. And those Eldrazi relics look rather like her dowsing crystals. Clearly, at some point Javad managed to gain control of Eldrazi tech, becoming a planeswalker, and ultimately ending up in Gensoukyou, where people started misspelling her name.

Rumia is Satan sealed in the form of a young blonde
Her name is alternately spelled Lumia, cognate to Latin lumen, just like the name Lucifer. Her usual "the saint was crucified" pose could be construed as a sort of deliberate blasphemy. Oh, and her darkness-manipulating ability seems perfectly appropriate for the Prince of Darkness. She may also be one of the more evil characters in a world of Grey and White Morality, as she's one of only a handful of youkai who explicitly expresses an interest in eating humans.
 * Um, doesn't "lumen" mean light in Latin? Because that would mean that "Lumia" is either a victim of Non-Indicative Name, or she may of had the power to control darkness and light at one time, which she could combine into one force and become enough of a threat to Gensokyo, that the Hakurei Miko of that time (and possibly Yukari as well) had to seal away that portion of her powers, leaving only a weakened version of her power over darkness afterwards.

To expand/play with the previous theory: Rumia is the Alpha youkai, and the Dark Messiah who will bring about the new Dark Age of Gensokyo.
I abide by a theory which seems to make sense with incorporating EX Rumia into canon, which is that EX Rumia was somewhat of the leader and master of all savage youkai. Back in the dark days when man-eating youkais were legion and mankind covered as night fell across the land, Rumia's screech used to strike fear in the hearts of every and all beings, as it ushered the arrival of a formidable hunter, the perfect killing machine - the perfect Youkai. The sealing of EX Rumia, reducing her to her diminutive state nowadays, paved the path for the Gensokyo we know today, a relatively peaceful place where man-eating youkais are rare and nonlethal duels are the rule. Rumia likes to assume a "crucified" position for she is the Anti-Martyr, the Dark Messiah of Youkais. Should EX Rumia be unsealed and left unchecked, Gensokyo would return to its primal state - a vicious bloodbathed country, where youkai oppress mankind and EX Rumia is the ultimate butcher...

Mima won't be in the Touhou games until Reimu gets more donations.
Her profiles in Phantasmagoria of Dim. Dream and Mystic square refer to her as the "(evil) deity of the [Hakurei] shrine". No one seems to visit the shrine, so Reimu is low on donations and Mima is low on faith. So unless the Hakurei shrine gets more visitors/donations...

The True Final Boss of the last Touhou game ever made will be Rinnosuke.
The plot of the game will most likely be the result of Marisa and Reimu getting into a fight that will end up completely destroying his antiques store. In a fit of righteous fury Rinnosuke will unlock his true power and transform into the fundoshi-clad MANosuke who then, wielding the legendary Kusanagi-no-Tsurugi he obtained from Marisa during Curiosities of Lotus Asia, will go on the warpath effortlessly owning all who stand in his way. The end of the story will see Reimu and Marisa join forces in a desperate last ditch attempt to stop him in a battle that will shake the foundations of Gensokyo and which will be hailed through the Internets as the most seizure-inducing, nerve-racking, bone-breaking, blood-boiling, ass-kicking, computer-destroying, explosion-laden fight of all Touhou.

And then they'll all go have tea.
 * You forgot the Extra Stage, where Tokiko (having Taken A Level In Badass) will steal Rinnosuke's heater and hold it hostage to get her books back.

Sakuya is a former werewolf.
In exchange for working at the Scarlet Devil Mansion, Remilia found a cure for her (although her powers are still linked to the moon). That's why she's often compared to a dog, and why Eirin is so surprised to see her in Sakuya's IN story mode.

Star Sapphire = Kaguya Houraisan.
First of all, they look exactly alike. You're probably thinking, "But Star Sapphire has wings!" Kaguya could have clip on wings, or Eirin has made a potion that can temporarily give wings to someone (most likely the former). Star Sapphire is also the only one of the Three Mischevious Fairys that isn't affected by the time of day. Neither is Kaguya. Both have resurective immortality. As for why they have different abilities, she could temporarily seal one of them while in each of her personas to prevent accidental ability discharge, or she could just choose not to use them. Also, we've never exactly seen Star's spellcards in action, so we don't know whether or not they are the same, and if they aren't, she could have two sets of spellcards. (This WMG has been brought to you by This Troper.)
 * Star Sapphire is about a meter high.
 * Kaguya takes care of that with Eirin's "shady drugs"
 * A doujin actually played with this by having Kaguya replace Sapphire.
 * And at least one fanwork has Kaguya turn Sapphire into her Mini-Me.

Chen is the ultimate Big Bad of the series.
Think about it. Ran(-shamaaaaaaaaa~) goes into nosebleeds and name-screaming whenever Chen does cute things is simply around her. People on Danbooru go "HNNNNNNNNNNNNGGGGGGGGG" over cute pictures of her. Chen's cuteness is simply a cover for her plot to take over not only Gensokyo, but the other side of the fourth wall!
 * There are some people who are unaffected by Moe though, including this troper. We perfer GAR anyway.
 * And even in her GAR moments, she still sets off some people's Tastes Like Diabetes radars.
 * You've obviously never seen X-CHEN! [NSFW due to ads]

The Gensokyo Barrier has sealed the Dreams from the Earth Alternate Universe it is connected to.
A "world where children don't smile" and tender fruits are extinct; this is why Maribel's and Renko's world is a little colder and grayer than ours. Such feelings aren't completely gone, but they are harder to get to.

Keine is a time crack youkai.
They both eat history. Not just that, but "The Pandorica Opens" tells that the cracks have spawned in every universe. Which would include Gensokyo.
 * Don't worry. Sakuya is a Timelord. They'll be fine.

Keine ate the PC-98 continuity.
Thus, things in Windows continuity can only indirectly reference PC-98 events and characters. Sadly, this theory would mean Mima is in fact gone for good.
 * Alice escaped by reincarnating herself as a human and becoming a Magician youkai. Yuuka escaped because she's Yuuka.

Keine has Yokai longevity.
She refers to a Hakutaku as a "beast" but it's really another species of Yokai. That one-three days of the month she's in Hakutaku form; her body is "not eating" that period of time. She has aged up to this point because Immortality Begins At Twenty. This will manifest one of two ways:
 * 1) That one-three days of the Full Moon; her Hakutaku body repairs any aging cellular damage that occurred during her human days. It will take a little longer for her to realize this as having natural white hair make lack of greying difficult to distinguish. So probably in her 40's/50's she'll realize.
 * 2) Her human self will age and die; and then she'll become a full Hakutaku.

Sakuya is somehow related to Aeon.
Both have silver hair, can manipulate time, and dress very formally (Sakuya's Meido next to Aeon's aristocrat might suggest he's her superior somehow). Aeon says immortals disrupt the flow of time, so Sakuya was sent to Gensokyo to make sure so many immortals aren't having an impact on the outside world. Her working for Remilia is just a facade so she can stay close to Flandre, one of the most powerful immortals, and observe any ill effects on the time stream. Also, similar to how Aeon only has limited influence beyond the Time Rift, only Gensokyo's fantastic nature allows Sakuya to use her abilities freely.
 * Flan? Remi has the ability to manipulate fate. If anything could affect the timestream, that'd be it.

There are two strongest non-god beings in the Windows continuity of Gensokyo: Koishi Komeiji, the extra boss of Subterranean Animism, and Fujiwara no Mokou, the extra boss of Imperishable Night.
Although it has been said that Suika, Yukari, Yuka or even Cirno are the strongest in Gensokyo and it has been heavily implied that it could be one of the heroines (Reimu and Marisa, namely, but also Sanae and Sakuya), this, in fact, is false. Canonically, the extra bosses of Subterranean Animism and Imperishable Night are stronger than all of them. And here's why.

(Just a note here: I'm taking the fact that every boss's power goes up by the same amount each stage; that is to say, Youmu is to Yuyuko what Shou is to Byakuren.)

Let's start with Embodiment of the Scarlet Devil. Since Reimu and Marisa defeat everyone in that continuity, that places the two of them at the top of the metaphorical food chain in Gensokyo. Next is Perfect Cherry Blossom. Since Sakuya was a stage 5 boss in Embodiment of the Scarlet Devil and she defeats everyone—even Yukari!--in that game, that must mean that youkai like Yuyuko or Yukari are weaker than Sakuya and, therefore, weaker than Remilia Scarlet. Since Reimu and Marisa defeated Remilia, though, the two of them are still at the top. They also go on to defeat Suika in Immaterial and Missing Power, which rules her out of the running as well.

Imperishable Night is where it gets a little weird. Since Reimu and Marisa are only stage 4 bosses in this game, that means that they are weaker than Reisen, Kaguya, Eirin and Mokou. Because every boss's power goes up by the same amount each stage, that means that Mokou is, canonically, the strongest up until this point. Since Mokou is never in any other games, though, we can't gauge her power level against other youkai.

Phantasmagoria of Flower View is also somewhat weird. Weak bosses such as Cirno and Mystia can go through the story and defeat a shikigami and a judge of the dead (as well as Reimu and Marisa, which further debunks their status as the strongest characters).

Reimu and Marisa hack their way through Mountain of Faith, which makes even goddesses Kanako and Suwako weaker than they are. The same goes for Iku and Tenshi from Scarlet Weather Rhapsody; since they're trumped by people we've ruled out like Yuyuko and Suika, they're out of the running.

(A word on the next two games, Subterranean Animism and Unidentified Fantastic Object: they are widely regarded as the hardest games in the Windows continuity of Touhou; therefore, I will rule their characters' power levels as a bit higher than the rest of 'em.)

Reimu and Marisa—stage 4 bosses from Imperishable Night—go to defeat every youkai underground, as well as Sanae Kochiya and Koishi Komeiji. Now, although Koishi is defeated by these stage 4 bosses, Sanae, Koishi's stage's midboss, goes on to beat the living shit out of UFO's bosses which, as stated above, is probably one of if not the hardest Windows Touhou games. Koishi, then, is stronger than even Nue, which makes her approximately around Mokou's power level, and high above youkai like Yukari or Suika.

Granted, I know that anyone can win spell-card battles (trust me, attempting to 1cc UFO lunatic will teach that to you...), but Koishi and Mokou are just the two that are the "favorites to win", shall we say.
 * You're only talking about who has the smartest and most beautiful spellcards. 'sides, Reimu and Marisa were Extra Stage bosses more than once. And the PC98 era didn't have spellcards yet.
 * Additionally, Mokou isn't really all that strong (probably equatable to Kaguya considering their similar abilities). In fact, she can be killed pretty easily, which would be great if you only had to kill her once. Her only strength is that she keeps coming back again and again. A nice in-game touch is that she has multiple, disconnected health bars; each time you kill her, she "resurrects" and moves onto the next health bar. If immortality is strength, Cirno is actually in the same boat, considering fairies, canonically, can't be permanently killed either (why Cirno doesn't have a number of lives in her game, she just has a motivation meter).
 * On the other hand, Mokou is the only character in canon to be an extra boss for Reimu, Yukari, and Ran at the same time. That's an extra boss, a main character, and the phantasm boss all at once. Anyone that can extra for all three of them simultaneously has to have a pretty high power level.
 * Mokou gets killed repeatedly because the player characters know she's immortal and thus don't have to hold back like spellcard rules normally require. They would've treated Eirin and Kaguya the same way had they known going into the fights that they were immortal too.

Touhou 13 is the NEW Duke Nukem Forever
As Duke Nukem forever was cancled, something MUST take it steed as there must always be a Duke Nukem forever. Touhou, was given this role. Think of it like this. Touhou 12 and 12.3 comes out. We then skip over Winter Comiket. Now Double Spoiler Comes out, as Another spinoff. Recently declared on July 23, Touhou, not 13, but 12.8 is coming out with the Fairy Wars. There will never be a Touhou 13, as the highly anticipated Touhou 13, which is the Storm after the calm (claimed by Reimu in TH 12.3) will never happen.
 * DEAR GOD, NOOOOOOOOOOOOOO!
 * And Duke Nukem Forever is actually being released.
 * 13 has now been announced

12.8 will chronicle how Cirno got her title as the strongest... of the fairies.
By diplomatic means, it seems, as Cirno freezes bullets instead of fighting the fairy head on. It seems Cirno is a pacifist when it comes to fighting Fairies. Guess she's a lot smarter than people assumed.
 * Well, it's a sequel to a story that at least took place after IN, and Cirno was calling herself the strongest fairy back in EoSD...

Kasen is/was an oni.
She's the titular character of a manga titled Wild and Horned Hermit. Her personal title is 'One-Armed, Horned Hermit'. It's not much of a stretch to assume that she has horns. The only horned characters so far are oni. Also has a shackle on her left arm, which is also an aesthetic so far unique to oni.

So, at some point she had a falling out with the oni (probably related to whatever cost her her right arm) and decided to live as the purest form of a human (or possibly being a hermit is the only way for youkai to be human). At this point she changed her name from Ibaraki Kasen to Ibara Kasen and broke off her horns (the remains of which are under those double buns).


 * Youkai (even the low level ones) can recover from all physical damage as long as they are not properly exterminated. According to Akyuu the knowledge of how to exterminate oni has been lost even before the creation of Gensokyo. So she must have lost the arm after becoming a hermit, especially considering eating hermits is fair game even in present days. Alternatively, she could be some kind of human/oni hybrid. Maybe she became a hermit to gain the strongest traits of both species or she needed the mental discipline (a quality not very popular among oni) in order to control her power, which she seems unusually shy about.
 * In Japanese mythology, it's entirely possible for an oni to become a hermit, and in fact that's the only real way an oni can overcome their baser desires. So if Kasen was unsatisfied with being a party animal like sake-guzzling Suika and Yugi, becoming a hermit would be the way to go.
 * That even fits in with the 'blue oni' WMG somewhere above this one on the page.
 * This is looking more and more likely, in chapter 9 of Wild And Horned Hermit she hides from Suika to "avoid being identified."

Mima returning in the windows games will be the Duke Nukem Forever of Touhou.
And it's totally gonna happen in 12.8.
 * Jossed. Still have hope for 13.
 * Duke Nukem Forever has been released. Clearly Mima returning will mark the apocalypse.

ZUN can actually draw very well. The reason he doesn't is because if he did, the epicness would collapse the universe.
Why not?
 * Why would he intentionally draw badly? Simple: He's like the guy who made Fourecks - anything he puts too much effort into becomes real.
 * In fact, he created a real copy of Gensokyo before he made the games, so there are now three Gensokyos in existence:
 * The true Gensokyo that exists independent of anyone, the one that his drinking buddy Yukari comes from;
 * The Gensokyo (copy) he created when he did some sketches that carried too much "reality" in them'
 * The Gensokyo (copy) that exists on the other side of the Fourth Wall, created by ZUN for the game series and remoulded by the countless hands of the fandom in their fanvids, fangames, and doujinshi.

Alice is actually infertile.
When she was human, Alice was infertile. In a last ditch effort to have her own child, she became a magician, and attempted to create a living doll using human souls. She was however punished for her sins and sealed in Makai (much like Byakuren was). There she encountered the witch "Alice" and challenged the witch to duel where she kills "Alice", steals her grimoire, and stole her title of "Alice" (here Alice is a title like Beatrice is in Umineko.). The new Alice then broke out of Makai and ended up in Gensokyo, where she is still trying to create a living doll. However TH 12.3 hints that she has created a living doll.

Remilia hired Meiling for no other reason but to be a butt monkey.
First, SDM doesn't really need any protection, there are enough competent fighters in SDM (including the fairies) and nobody is bothered enough to attack SDM anyway. Second, if SDM really needed protection, Meiling's level of power hardly does a thing, both Sakuya and Patchouli can fend off invaders far more easily than Meiling. If Remilia really wanted to have the gate well defended, surely she can pick someone with a higher level of competence. Third, Meiling is a melee fighter, or martial artist, which means she is a lot more "durable". Remilia and Sakuya must be pretty bored by themselves, and Patchouli never ever comes out, so they need someone else other than the fairies to "play" with, and Meiling seems perfect for that role, more so than a gate guard.
 * Hong is there to dispatch any riff-raff that attempt to enter the mansion, something she is easily capable of doing (though she is hardly a planet-crushing menance, it is often forgotten Hong is still a capable fighter). It wouldn't make sense to bother either Sakuya or Patchouli with such things, as they both have more important duties Remilia wouldn't want them shirking. It is just that in Gensoukyou nearly everyone is a capable fighter, Reimu and Marisa among the best, and Hong is constantly Overshadowed by Awesome, which is what has turned her into a joke. Besides, Sakuya and Patchouli are too serious and obsessive to bother abusing the guard, though I wouldn't put it past Remilia.

The reason Alice is so afraid of going all out in the Windows games is because of the events in Mystic Square's Extra Endings
Yeah, you're not misreading that; Mystic Square is the only Touhou game to have a proper ending and credits sequence (actually a list of all the characters in the PC-98 games) after its Extra Stage. They all involve some rather humiliating thing happening to Alice. . Under that treatment, who wouldn't be worried about going all out? THEY MIGHT DO IT AGAIN!

Revenge wasn't the only reason Cirno started the war with the fairies
It was mainly to test her newly developed bullet freezing powers on weaker opponents, once she was confident it was awesome she went for the true targets of her revenge, that infernal Miko and Witch who think just becauses beat her X amount of times they're stronger! The very fact her first action after beating the fairys is going to fight  in the extra stage supports this.
 * She's been able to freeze enemy bullets since PoFV.
 * Well way to kill my fun. I suppose I could argue those are more like Bombs than the Freeze near infinitly she has in 12.8.
 * Ah, but there's some evidence in Fairy Wars that suggests it may actually be taking place before Phantasmagoria of Flower View.
 * Cirno doesn't meet the Three Fairies until after MoF. Assuming that SaBND's chronology is linear, anyway.

The presence of youkai of non-Japanese ethnicity implies that there are non-Japanese Gensokyo counterparts.
This explains, for instance, where the Chinese Girl characters come from.
 * Not exactly. The current form of Gensoukyou is unnatural, a barrier against the lessening of fantasy. The foreign characters could have made it into Gensoukyou before this was necessary. That said, there's nothing stating that Gensoukyou is unique, and the Lunar Capital shows that you don't need a boundary youkai to set up something like that.
 * Is not only the Lunar Capital, there is the hell of blazing fires from SA with is underground but not *really* underground. There's a great chance that other legendary magical places also exist in sealed form like Avalon, Atlantis, El Dorado, Shangri-La Mount Olymp etc. And probably the entire Makai and Netherworld.
 * The abandoned hells are in fact actually underground. Hence Okuu's powerup resulting in a geyser.

Prior to working for Remilia, Sakuya was a murderer
Time freezing and space manipulation would make it very easy to clean up after oneself; by targeting out-of-the-way places, she could avoid attention from anybody powerful. On one occasion, by pure bad luck, she picked a house full of vampires and got smacked around by a rather irate Remi. Remilia saw the potential for easy meals and offered Sakuya job looking after the SDM instead of turning her over to Reimu/whoever handles homicides in Gensokyo/chowing down herself; when she accepted, Remilia picked a pseudonym so nobody could pin anything on her.

This explains Sakuya's fascination with knives and skill at concealing them, as well as the Serial Killer theme to a lot of her spellcards. It also might explain why an alleged human is comfortable making blood-based foods for her mistresses - she enjoys it, and perhaps even partakes herself.


 * A very interesting theory, and a highly recognized one, as far as I know.
 * And if the Lunarian theory is true and she is much older than she looks then maybee there is a chance she is THE Jack the Ripper. Since Jack the Ripper mysteriously dissapeared and Yukari having a habit of spiriting away people she finds interesting. A renowned serial killer would have been irresistable to her. The barrier was erected 1884 and the last known murder of Jack the Ripper happened 1889 witch means Gensokyou existed before Jack dissapeared.

Gensokyo is the name of a mental hospital
...and all the fantasy elements and adventures are the collective result of a bunch of fractured minds coping together. Each character's individual quirks actually come from their neuroses:
 * Reimu and Marisa suffer from intense hallucinations, which is why most of the world seems to be built around them. They're also paranoid, leading to them picking fights whenever they think anything strange happens.
 * Also, the two of them, along with Yuuka, were the very first patients of the hospital. Because they didn't have much company, they started to make some imaginary "friends" that they could fight with (well, there was Yuuka, but the caretakers thought it was better not to let them in contact with her. Not that they succeded, of course), along with recurring character Mima who Marisa claimed was her teacher and that Reimu could never defeat her (thus their rivalry). Eventually, more patients ended up in the hospital, thus there was no need for any imaginary friends when the girls finally had someone to interact with(thus explaining why the PC 98-era is Ret-Gone).
 * Marisa's father abused both her and her mother, Mima. His beatings led to Marisa's severe paranoia of most males, which is why there are next to no males in Gensokyo, (other than Rinnosuke, a friend who visits her). Mima, unfortunately, was killed when she managed to get Marisa out of the house and to the hospital. For a long time Marisa was not informed that Mima was dead, and continued to believe she was around for her. Her "visits" were some of the aforementioned hallucinations. After a while they broke the news to her, and she was devastated. Reimu managed to move on, however. Marisa still occasionally hears her voice or sees her in the distance, though. This led to her belief that Mima was a "ghost" and one of her "caretakers". She still follows hints of "advice" Mima gives her, considering her as a brave rulebreaker who would let her daughter do things like beat up other patients and steal for the greater good.
 * Yuka was a schizophrenic gardener who made friends with the flowers in her garden, believing they could talk to her. She was sent away to Gensokyo for brutalizing an unfortunate soul who accidentally ruined her garden, killing several of her imaginary friends.
 * Rumia had always been a troubled child, but her insanity finally reached a climax when one night, she crept out of bed and assassinated both her parents. She has been found eating their bodies, calling herself a "youkai".
 * It was January and -35 degrees Celsius outside when little Cirno's abusive drunkard of a father kicked his simpleton of a daughter out of the house with nothing but a dress to protect her from the biting cold. Cirno wandered around, slowly freezing to death. By the time someone helped her, it was too late. The cold had irreversibly affected her nervous system, turning an already simple child into a mental retard, as well as completely inuring her from any sensations in her members. This lack of pain and feelings has led Cirno to believe she has gained immunity to, and subsequently control over frost, of which she is extremely proud.
 * Daiyousei is a quiet, homeless, but (relatively) mentally well girl who alerted child welfare when she found Cirno. She quietly comes and goes, seeming to appear and disappear like a fairy to most of the the inmates. The nurses allow these visits since Cirno is always happy to see her.
 * Shinki was apparently a woman who was traumatized by witnessing or being part of some occult ritual, or she herself conducted it.
 * Hong Meiling is narcoleptic and a recovering drug addict (see: giant catfish), at a specialist hospital because the latter restricts treatment for the former. She comes across as a doormat in the fantasies of others because she's lucid enough to know that playing along is best for everyone.
 * Sakuya is the one who initially insisted she be institutionalized for her drug problems. Meiling jokingly says she thinks she can manipulate time and throw knives because she always seems to teleport around and start poking her mid-conversation, though she realizes she just fell asleep.
 * Alternatively, Sakuya was a batshit crazy knife nut serial killer, so skilled she never left any traces after her murders, always getting away, almost as if she could stop time. She would have gotten the death penalty (or lifetime prison), but the attorney pleaded insanity.
 * And with that alternatively, Meiling was Sakuya's partner in crime and got the pair caught when she fell asleep while on lookout. Despite the risk, they pair are allowed to stay together since they keep each other controllably calm, though they are kept a few rooms from everyone else, not least because Meiling is a masochist to Sakuya's sadist.
 * Remilia comes from a family of nobles, but their fortune was lost. In desperation, Remilia went insane, becoming a serial killer suffering from a vampire complex, hiding in her decrepit mansion during the day. She would kidnap and kill people to drink their blood until she was finally stopped. She became good friends with Sakuya, who respects her as being the more hardcore of the two. Her sister Flandre (something with the genes of this family is just wrong, maybe it's all the cosanguine marriages between nobles) suffers from psychosis, and gets violently destructive when she suffers a psychotic break. She lives in a more secure ward downstairs from the others for everyone's safety, where Remilia regularly visits her.
 * Alternatively, the two are not actually related. Both suffer from abandonment issues and have formed some sort of familial bond as a defense mechanism.
 * Yukari is an old woman who suffered a stroke that severely damaged her spatial perception - she thinks she can manipulate the borders between places because she constantly misjudges where things are. Ran and Chen are her daughter and granddaughter.
 * Youmu constantly has out-of-body experiences, leading to a delusion that she has another, "ghost" half. This is a genetic condition, as evidenced by the history of her grandfather Youki, who was similarly delusional, but was cured. He now runs a fencing dojo. Youmu used to be one of his students, but left after her condition became too disruptive.
 * Yuyuko suffers from a neurological condition that makes her think she's always starving. She has to be chained to a chair or she'd bother everyone in a hysterical search for food, or if she could find enough, eat herself to death. There's a cherry blossom tree outside her window, and Youmu is her wardmate.
 * Yoshika may suffer from the same condition Yuyuko has except she is bound to the wall of a room, completely unable to move her arms and legs lest she attempt to eat them, too.
 * Nitori has an acute case of Asperger's and an intense fascination with machinery. She's in Gensokyo to treat her debilitating social awkwardness, and has just started to come out of her shell, with some thanks to Marisa.
 * Kanako suffers from a severe God complex, or more precisely a Wind God complex. Suwako has an extremely weird combination, she has a God complex, and she also thinks she is a frog, hopping around like one.
 * Sanae is Kanako's daughter, and visits her mother often. She plays along with the patients' escapades, and, as of late, is becoming more eager to play make-believe, especially now that she's compared it to her comparatively dull reality. Her humans-first attitude is a reflection of her annoyance with many of the other patients.
 * Utsuho Reiuji worked at a nuclear central until a catastrophic nuclear accident happened and she was exposed to massive amounts of radiation, deforming her foot, forcing the amputation of one of her arms and its replacement by a prosthetic arm, and twisting her brain. Utsuho believes that she has gained superpowers (oh, and that she's a bird). She likes to wrap herself in a sanitary blanket like a cape, and make up ludicrous plans to burn the asylum to the ground.
 * Alternatively, Satori is a patient with a form of autism from so far into the deep end of the spectrum that she finds normal social interaction impossible. Instead, she keeps pets, a cat (Orin) and a raven that comes past every day because she feeds it (Utsuho). Since she can think well enough to require stimulation (just being rather sideways about it), she reads the facility's medical texts; since she has a habit of diagnosing others with the same things the nurses say, they all think she can read minds.
 * Aya was once a world famous journalist but one day had her cover blown while following some highly illegal lines of investigation. The ensuing storm saw her reputation and publishing history made a joke practically overnight; since she lived for her job, this was enough to make her completely snap. She was admitted for her mental wellbeing, but since she's mostly harmless (running back and forth taking photos for the big story she still believes she's chasing) she's allowed more freedom to run around than the others, also making her think she's incredibly fast.
 * Aya's co-worker, Hatate, was so shocked by Aya's fate that she went into seclusion. She's now effectively a hikikomori, giving up high-profile journalism to write relatively boring but risk-free stories from home, and really only ever leaves to pay Aya an occasional visit. Aya, in her current state of mind, believes Hatate to be her rival; Hatate plays along for Aya's sake.
 * Komachi was involved in a riverboat accident that left her with brain damage that chiefly crippled her sense of balance to the point she can't even stand on her own - she needs assistance to move anywhere in a way that isn't an undignified crawl. This, combined with her train of thought now derailing at random, gives the illusion to other wardmates that she's extremely lazy. This is actually far from the truth - she still possesses the rest of her mental faculties, has an average IQ, and can communicate just fine; she just lacks mobility, leaving her very bored a lot of the time. Consequently, she has regular visits from a tutor to continue her education:
 * This tutor - Eiki - doesn't have any training dealing with the mentally unwell (making her seem extremely moralistic to them in contrast to the nurses) and favors a light tap on the head with a ruler when Komachi loses track of what she's supposed to be doing. "Miss Shiki" is rather strict and has very traditional values, making it difficult for her to interact with the more delusional patients.
 * Parsee has an inferiority complex that she expresses through emotional abuse, and often has to be isolated for the sake of the other patients' well-being; this further cripples her self-worth.
 * Suika, Yuugi, and ZUN are patients of a nearby alcoholism recovery center. ZUN is Aya's boyfriend, and visits her fairly often. He also somehow manages to regularly smuggle beer and sake into his room, where he has parties with the other two.
 * Byakuren is a nurse who tries to make things better for everyone, but constant exposure to the patients causes her to fear for her own sanity.
 * Kaguya comes from a wealthy family, but social issues, autism, and her NEET habits eventually led the her being committed for care. Since she has such a rich family and good health care cover, she has her own private nurse, Eirin. Eirin herself should be concerned only with Kaguya's care, but her high qualifications are so useful she occasionally helps out with other patients.
 * Reisen is a soldier from the JSDF who suffers from PTSD stemming from a moment where she abandoned her unit during a crucial operation. In spite of her being unwell, she now acts as a sort of bodyguard to Kaguya and her entourage, scaring off offenders with a glare that seemingly drives its victims mad with fright. Tewi, on the other hand, is a shameless sociopath who exhibits anti-social behavior, and came to Gensokyo as a result of being found guilty of depraved-heart murder after a prank went horribly wrong.
 * 'Nue' is just the nickname of a girl with Multiple Personality Disorder severe enough that, with her parents having abandoned her, nobody can figure out which (if any) of the personalities is the original. Each personality has it's own style of dress; while it doesn't fool the nurses (and in fact helps them know 'who' they're talking to), it's enough to make other patients think she's a shapeshifter.
 * Kyouko arrived after becoming lost in the mountains during her junior-high years. Wandering around and trying to answer the calls of search-and-rescue teams, she developed severe obsessive-compulsive behavior which compels her to repeat back loudly anything anyone says to her. Her disorder is also the reason she can regularly be found sweeping the entry of the patient ward. Her habit of greeting everyone cheerfully in the mornings is the result of a phobia of being alone (also due to her unfortunate experience).
 * Kogasa was abandoned at birth to an orphanage, and due to her heterochromia, was seen as a freak by all the other orphans. Due to this, she has come to believe that she literally is a monster, and developed a compulsion for scaring people in order to gain attention. She also carries around an umbrella at all times, believing it to be her only friend.
 * Murasa was a sailor, until one day, the ship she was captaining hit a reef and sunk. Being the sole survivor of the tragedy, she believes she's directly responsible for all of those deaths, the resulting grief eating away at her sanity until she was forced to be instilled into Gensokyo after attempting to drown herself.
 * Alice was a shut-in with a rampant doll obsession, to the point of preferring to do maintenance on them than take care of herself, and occasionally having delusions of them coming to life and moving around. She believes herself to be completely sane, though, and so acts rather haughty towards other patients.
 * Miko was a student at a nearby university majoring in Japanese History. The stress of her studies caused her to snap suddenly one day and she came to believe that she is the resurrected Prince Shotoku. Futo and Tojiko are simply two friends who are willing to play along using the historical clan names of "Mononobe" and "Soga".

...and so on. Each new 'game' is a pecking order being established as more patients are committed.
 * I challenge anyone to make a fanfic for this!
 * Done. Maybe I'll even make it not a oneshot.

Yukari is a tanuki.
If she has human ears, they've never been shown due to her hairstyle. Her hat would conceal a pair on top of her head while her large dresses (or powers) would easily hide a tail. More importantly, the mythos of the animal would match her tricky nature, tendency to spirit away people and objects, and constant sleeping. Her household hierarchy of Shikigami even becomes Japanese wordplay. Tanuki->Kitsune->Neko.

Yukari has control over quantum phenomena
This explains her absolute reality warper status and manifests itself in her most powerful spellcard Boundary Between Wave and Particle. Yukari may be the ultimate quantum mechanic.

Yukari vacations in the Bermuda Triangle
Many people "disappear" in Bermuda Triangle... possibly because Yukari is bored and invites them over. If you would call opening a boundary and teleporting them an invitation.

Mokou and Kaguya were dummied out of Hisoutensoku because their planned movesets at the time made Gill look like a cakewalk.
the way i pictured them is them acting like gill when KOed after triggering a certain card only they can resurrect several times (due to being able to have several cards) which would lead to a long and boring fight which is probably why they got dummied then cut out of the game because there wasn't a way to make this balanced.

Games 11 and 12 were experiments by ZUN to circumvent the usual Touhou stereotypes into which he had forced himself by previous games.
Subteranean Animism, as the first of these experiments, only possessed small deviations. Instead of the character with the most authority also being the most powerful she was merely the Stage 4 boss, instead of the final boss being some ancient, epic individual with a grand history she was merely a stupid bird with powers far beyond her comprehension, and there was even a sort-of Mission Control.

Undefined Fantastic Object, however, possessed far greater variances. There was no great disturbance to investigate or powerful youkai to thwart, only a ship in the sky and a group trying to free their friend. Only one of the characters were not related to the plot at all, and she was specifically there to surprise people. The source of the original problem was not the final boss, but instead the Extra boss. There were two male characters, albeit one only in the backstory and one as an assistant, and three without any headwear, hair decorations or animal ears of any kind.

The reason that such a relatively large time has transpired between 12 and 13 is ZUN is attempting to make it his biggest deviation yet but is having troubles with it possessing numerous new elements while simultaneously remaining essentially a Touhou game.

Meiling is a really sucky Chinese dragon.
This would explain Meiling's magic, her penchant for guarding things, and how exactly she is a youkai. Dragons often take the shape of humans, so it stands to reason that in Gensokyo, where even spiders are lolis, a dragon would simply stay in human form (though more likely forced to stay that way).

Besides, dragons are hard to draw.

The Hourai Elixir doesn't keep hair from graying.
An illustration in the fourth chapter of Cage in Lunatic Runagate shows pre-Elixir Mokou with dark hair, but no explanation is given as to why it turned white. This is obviously due to a flaw in the Hourai Elixir: even if you drink it, your hair still grays as if you were aging normally! (Kaguya's hair kept its color thanks to another one of Eirin's shady drugs.)
 * Alternatively, Mokou's hair grew out until it reached its maximum length and turned white from overexposure to sunlight, while Kaguya retained her black hair because she never goes outside.
 * Or one of them dyes/bleaches her hair. Kaguya to keep up the appearance of youth, or Mokou in order to less resemble Kaguya.
 * Another theory is that it was a side-effect from Mokou attaining the power of the Phoenix. Whatever it was that enabled this was so warping, it changed the hair-color of an Eternal. (Popular Fanon is that she actually absorbed the power of a god-like Phoenix; which would have killed anyone else.)
 * My theory is that, since two sips of the Hourai elixir will make it so the drinker never gets sick, it strengthens and stimulates the immune system drastically. Mokou's immune system destroys the black pigment in her hair, along with contributing to her frequently being on the verge of death. Either Mokou's immune system was already much stronger than Kaguya's, or she drank more of the elixir, or she has multiple genes for black hair and her body intreprets the rna transcripts from it to be viral. Either that, or Kaguya's immune system was very weak before drinking the elixir (possibly part of the reason why she drank the elixir in the first place.)
 * Another personal theory (though it has less merit...): Hourai just turns your hair a funky color. What's the default hair color for Asian girls? Black. The opposite of black is white/gray. Reisen and Eirin both have white/gray hair, so we could possibly assume that white/gray is the default hair color of Lunarians. Kaguya? A Lunarian with black hair.
 * Or maybe Lunarians, unlike humans, simply never have their hair color change. Lunarians are all "immortal" in the sense that they don't age once they reach adulthood, but they can die by other means like illness, injury or starvation.
 * Mokou's hair is black...but it's all covered in ashes.
 * Rather, it is ash. A continuous state of burning to cinders instantly yet retaining form.

Mima's true nature...
Mima is just a normal chick. I mean, she got killed eventually, but death happens to everyone, yeah? And she just so happened to be a magician, which, of course, isn't anything terribly special. So she's just died, and is minding her own business, sitting at the banks of the Sanzu River waiting for the lazy Shinigami to get to ferrying her across, when suddenly she's GRABBED FROM BEHIND AND DRAGGED OFF. (Explicitly stated as what turns one into an Evil Spirit, what Mima is referred to as) She, like any sensible person, Screams her lungs out, but Komachi doesn't even think of helping her. So, eventually, when she's completely within the bounds of the living world, she's got her powers back, and just beats the crap out of the Youkai that carried her off and kills them, explaining why she isn't under their control. Well, now she can't do anything to the one she dragged off... But, she's got no clue how to get back to the world of the dead. So she figures, she's not exactly "dead", explaining her dialogue in PoDD. But she realizes... She ain't going back. So her morals essentially vanish. That's what makes her "Evil". But... It wasn't her fault. So she wants to revive herself, if only to get a second chance. But in the meantime, she just wants to make the lazy ferryman's job as hard as she can- What the hell, I'm screaming and you just keep sleeping?-, and the only way she figures she can do that is just kill as many people as she can. Without morals, that's no problem to her conscience. It's not that she doesn't like humans, no! It's just, she has no value for life anymore. These people, they're getting a better end of the stick than her anyway! So she's just like, "It doesn't matter. I don't care anymore. Just make that Shinigami pay somehow... She doesn't even think of working!" SHE HAS THE SAME GOALS IN MIND AS SHIKIEIKI. SHE JUST GOES ABOUT THEM A DIFFERENT WAY. (Marisa got abandoned for using magic. She was misfortunate. Mima took a liking to her, so she became her teacher.)
 * This Guess deserves a Fucking Awesome seal of approval.
 * This is indeed a good theory and you should feel good.

The original Reimu, Marisa, and Alice were all killed shortly after Mystic Square.
In response to this, Yukari, Mima, and Shinki all went on a Roaring Rampage of Revenge and killed nearly all of the PC-98 cast.

Then Yukari kidnapped three girls from somewhere and used border hax to brainwash them into being Reimu, Marisa, and Alice—she missed the memo on Alice's age—resulting in the three almost-exactly-but-not-quite-entirely-unlike girls in the Windows games.

Mima and Shinki appreciated the gesture, but weren't comfortable with the Replacement Goldfish scheme, so they made Marisa and Alice neighbors for their mutual protection, then quietly abandoned them and receded from society. Out of loneliness, Shinki started teaching the imprisoned Byakuren some of her spells.

Yuuka survived the PC-98 massacre, but the experience and the loss of her servants and Mugenkan gave her a lesson in humility, which is why Windows!Yuuka has toned down the evulz, and is homeless and without servants. This might also be why Eiki rebukes her for having lived too long.

The new characters in the Windows games are new youkai moving in, or old youkai who made themselves scarce during the PC-98 days/slaughter and are emerging again.

Two females can have children in Gensokyo.
The would explain why there can be a population of near entirely females, yet there isn't a huge population drop. This would result in more females, since they only have X chromosomes to give, their child would need to be a female. The men are few and far between because they still have a 50% chance of passing their X chromosome as well, and may well eventually die out.
 * The youkai population is almost entirely female, and not only are their reproductive methods unknown but even the weakest live for extensive periods of time. The human population however, of which we almost never see, is more evenly divided between females and males.

The Soccer Ball is actually Reimu's Yin-Yang Orb painted over for the occasion. That's how it survives every city-razing blast﻿ it receives.
Credit goes to Fenrirknight7 in the Youtube comments.
 * This would explain how Reimu somehow comes up with a "Super Technique" just from Soccer. ...okay, Soccer that has everyone concentrating their super god-like powers on the ball.

Hakurei Shrine Maidens do not take vows of chastity.
How else is Gensokyo going to survive when Reimu inevitably dies of old age?
 * Except that the people in Gensokyo don't seem to physically age whatsoever. Everyone in Gensokyo has modified DNA that can replicate without end.
 * According to The Other Wiki, Shinto religious professions do not require chastity to begin with, so... duh? Plus, it's canon that Reimu's ancestors served the shrine before her, so logically she wouldn't exist if they were bound to chastity.

ZUN will eventually be forced become a Youkai in order to survive.
Lets face it, he's looking pretty old for a guy in 20s or 30s, an alcoholic, and quite possibly poor. His fans (or Yukari) WILL find a way for him to live, and this may or may not lead to him gaining immortality via Youkai transformation, ala Alice. Alternatively, somebody will find a way to make the Hourai elixer.

Rumia is a Grue.
It is pitch black. You are likely to be eaten by her.

Reisen has the wild card
I got the idea when reading the following lines from the Alternate Interpretation compendium on TV Tropes: "So, basically, Reisen is the ultimate of not being able to tell anything. She's, I think this is the right term, somewhat sociopathic with the ability to apparantly completely change her personality to match whatever she needs for the current situation. For all we know the cute, helpless bunny appeal is all one big facade to rule us in."

This is precisely what the wild card does, it lets you change your persona, your personality, at a whim. Meaning that if she manages to somehow get Sakuya's "The World", she might even be able to seal away the moon. Note that this has hardly any basis in canon. Which probably is why I think this would be awesome.

Kasen Ibara is the new version of the previously Dummied Outed Satsuki Rin
How does this make sense, you ask? Well, Kasen is called a "horned" hermit, and kirin do indeed have horns (not that I'm stating that she's a kirin, although it could be a possibility...). Also, the entry for Satsuki Rin states that she had the attack types Flower Sign and Wind Sign associated with her, and the name Kasen is written with the characters for "flower fan", so...
 * I would like this: let's see what kind of spell cards she knows, before deciding.

The PC-98 games and the Windows games can be reconicled with each other
This is basically just me using WMG as a vehicle for putting down my various explanations, so here we go. Let's start with Marisa:
 * In the Windows games, one of Marisa's signature "signs" is the "Love Sign" series, which includes Master Spark and Non Directional Laser. Now, just from those two, you may think it's just for laser-style cards. You'd be wrong, as she has a few cards which are nothign but lasters that do not use any derivative of "Love Sign". Example: Light Sign: Earth Light Ray, and its upgraded form: Light Blast: Shoot the Moon. Love Sign isn't even used for all derivatives of the Master Spark: Once she reaches Final Spark, the supertitle has changed to Magicannon; similarly, Blazing Star is supertitled Comet, even though it uses a Master Spark for propultion.
 * Conclusion: the "Love Sign" supertitle is actually used for spells that Marisa steals. We know from canon found solely in Windows games that this is true for Non Directional Laser, and Master Spark derivatives only stop using "love" in the supertitle after they've changed so much as to not be even close to the original spell.
 * What does this mean for PC-98? Well, we know that Yuuka Kazami was the first character to use something like Master Spark: it was one of her strongest moves in Lotus Land Story. In Lotus Land Story, Marisa's self-stated goal was to steal Yuuka's power. Judging from her constant use of Master Spark in the Windows series, I'd say that she succeeded.
 * Speaking of Earth Light Ray: in Imperishable Night, ZUN's comments about the spell say that at this point in the battle, Marisa's been pushed to her limits; to the point that she's pulling out a really old spell. The spell is made up of thin lasers shooting up from the ground ad various angles. It is extremely reminiscent of Marisa's "extra attack" in Phantasmagoria of Dim. Dream, albeit modified to be an actual spell card pattern, and named.
 * This may sound like a far-fetched comparison, but then Phantasmagoria of Flower View came out. This being a Windows game, all the Extra attacks were named, and guess what? Marisa's is a copy of her Extra Attack from PODD... named Earth-Light Ray.
 * Next, let's take another look at Yuuka, shall we? In addition to supplying what is now Marisa's signature move, the oddly relocated flower youkai is mentioned in regards to Reimu a few times. In Perfect Memento In Strict Sense, Akyu mentions a rumor that Marisa once defeated Yuuka (though she doubts it). Whatever Akyu believes, there's no mistaking things when Reimu mentions having defeated Yuuka once before, when she talks to her in Yuuka's scenario in Phantasmagoria of Flower View. Yuuka may not have been talking about that at the time, but Reimu certainly remembers fighting her once before.
 * Conclusion: Well, barring the idea that there was some other big fight between Reimu and Yuuka aside from the one at the end of Lotus Land Story, it appears that this is a direct reference to said game, of which Yuuka was the final boss.
 * Problem: Despite the name, the incident in Lotus Land Story had nothing to do with flowers, and flowers were what was causing Reimu to accuse Yuuka of being involved.
 * Reimu says nothing about the flowers when she accuses Yuuka. She simply says "Everything went back to normal when I defeated you back then". Which is true. In any case, the Lotus Land Story incident involved a massive influx of evil spirits, which is sort of half of what the POFV incident is (overflow of spirits and the crazy flowers). Plus, Yuuka's newly-revealed identity as a flower youkai makes her all the more suspicious to Reimu. And nobody's ever accused Reimu of not beating up on someone for being very tangentally related to the incident.
 * Er, LLS was about large numbers of youkai (this being before youkai were established as the dominant species) coming out of nowhere, not spirits.
 * Oh, sorry. Misremembered. OK, so Reimu's reason for attacking Yuuka is downgraded to "she's tangentally related to the incident" (flower youkai) and "she's caused trouble in the past", which is about two reasons more than Reimu generally needs. In any case, I was never talking about Reimu's reason for attacking Yuuka; the important bit is that Reimu remembers fighting Yuuka, so unless this is a different Yuuka Kazami, with the same outfit, who has fought Reimu before...
 * Last but not least is Alice. She's a bit of a bucket of worms. Met in Mystic Square as a child in Makai, showed up again in Perfect Cherry Blossom as a grown woman (well, as grown as anyone can seem to be in this series). Not only that, but now she's described as a human that became a magician youkai, when it was initially assumed she was a Makai resident demon, like veryone else in Mystic Square. We can accept the idea that Shinki can make ordinary humans, or that Alice was "adopted" by her, if you will, but what about her age?
 * The explanation is in the Perfect Memento description of Magicians. According to said entry, there are three stages of being a magician: First is a completely human magician, who must cast magic through use of potions, reagents, and magical items. Marisa is one such magician. On the furthest end of the spectrum are "complete" magicians, who have learned a magic to abandon their "temper"; locking their age and extending their life. Patchouli is often regarded as one of these. In between the two is a transitional phase; occupied by youkai born as magicians, and humans who have learned as pell to become like said youkai. They can cast magic on their own, but still age and have a limited lifespan until they become "complete.
 * My theory is that Alice is one of these stage-two magicians. She has become a magician and abandoned her life as a human (or Makai-human), but she still ages, and that is the key. She appears to have aged between Mystic Square and Perfect Cherry Blossom because she is a Magician Youkai who still ages. She no longer needs a book to cast magic (though she still has it locked up and with her).
 * The problem was never that Alice aged, it's that she aged well beyond what should be possible in the time between the games. She seems to have gained a good ten years, while Reimu and Marisa are the same age as ever.
 * A growth spurt is possible, or perhaps Makai humans age faster. By the way, there are a pair of points I neglected to mention earlier. In Perfect Cherry Blossom, if you're playing as Reimu, Alice most definitely remembers Reimu. She calls her "old friend" and is annoyed when Reimu doesn't seem to remember her (perhaps because she's grown so much). Also, there's something about her book. In the intro to the "Grimoire of Marisa" Marisa says that the name is very definitely NOT a ripoff of Alice's. However, Alice's book is locked up and we can't see the title... except in Mystic Square, the PC-98 game, where we can see clearly that it reads "Grimoire of Alice". In any case, the book looks very much like the same one. In light of those two tidbits, I find it far more logical to assume she had a growth spurt/aged slightly faster than to assume that this is a different person, named Alice Margatroid, with the same book, who remembers Reimu.
 * It's also possible that... Alice didn't really grow all that much in between Mystic Square and Perfect Cherry Blossom, and it's simply a case of Not Drawn to Scale. If you look at Reimu and Marisa's portraits, or even the CD cover art, they honestly don't look much older than Alice, if at all, during Mystic Square. In PCB, she only seems much older because she's not wearing such childish clothes anymore.
 * Well, that and the fact that she acts like a young girl in MS, and like a reasonably mature adult in the Windows games.
 * Also, the only source that ever describes her as a human is Perfect Memento in Strict Sense. Every official profile given by Word of God never refers to her ever having been a human, and in fact, suggests otherwise. The article on Magicians seems to suggest that only the most devoted of human magicians can gain the skills necessary to become a youkai, which is something even Marisa hasn't achieved yet, but Alice's magical prowess is always described as average and even Akyu calls her a novice when it comes to magic. In fact, the official profiles always seem to make it a point to mention that she's a youkai as a species, calling her a "genuine magician."
 * Er, PMiSS makes a point of stating that magical knowledge has become easy to aquire, and that young magicians are now common.
 * And there are my explanations of major bits of evidence, and explanations of seeming inconsitencies. Further investigation may be necessary on a few fronts, but I feel that's the most major points explained.
 * One last thing: Reimu explicitly mentions having gone to Makai previously in UFO.
 * No, no she doesn't. She indicates familiarity with Makai, but it's entirely possible she'd simply heard of it.
 * The first boss in Lotus Land Story was never actually named ("Orange" being a nickname from the game coding), so she might have been a younger Meiling, prior to her service with the Scarlet Devil Mansion—during which she was given a new uniform to wear. She's not used to the sedentary life of a gatekeeper, so she dozes a lot out of boredom and isn't very good at danmaku... but it's a step up from being a Stage One boss!

Marisa is part (half?) Dutch.
It's the simplest and most logical explanation for the name and hair color. Ignore the Youkai with similarly western names and blonde hair, they are stated to be thought impossible by the outside world.
 * Sanae. Green hair. Sure, she's part god, but only a bit (and Suwako is blonde).
 * I've always thought that it was a reaction to the magic of Gensokyo that made Sanae's hair green. As for Marisa, I blame the mushrooms, if not her own magical training, as the cause.

Lily White/Black is a subspecies of fairy, not an individual.
Thus, in Phantasmagoria of Flower View, when she comes back after getting shot down, it's actually a different one replacing her.
 * Perfect Memento in Strict Sense refers to Lily as an independant character, so this is unlikely. Besides, fairies can easily return even after vaporisation, as well as being deeply stupid, so her reappearing for multiple beatings isn't unusual.

Youkai, perhaps even Gensoukyou as a whole, operates under a feudal system.
Weaker beings offer their loyalty and service towards a more powerful individual in return for their protection and use of their residence. Sometimes (in the case of the Konpakus) even entire families devote themselves and their descendents to an individual. This is why so many petulant, self-obsessed control freaks manage to acquire devoted followers, as for youkai (and some humans, if Sakuya is any indication) nothing is more important than power.

This is also what makes Satori and Byakuren so unusual, the servants of the latter retaining their loyalty even without her protection and the former commanding the loyalty of beings more powerful than her simply because of her kindness.
 * It's kind of mentioned repeatedly that most youkai are independent. And the tengu have a caste system, which isn't quite the same. Oh, and the Konpaku are humans, more or less.

Marisa's father is actually her adopted father.
Mima, during one of her usual attempts to make herself more powerful, was constructing a servant worthy of her majesty, but instead of a youkai she managed to create a human that simply possessed magical abilities. Instead of going to the trouble of destroying it she opted to dispose of it instead, and one day, with absolutely no-one noticing how it got there, a blonde-haired baby appeared in the Human Village. Mister Kirisame, long obsessed with the unusual and unexplained (and predictably a frequent customer of Kourindou), decided to adopt the baby and name her Marisa. For a while things went well, until Marisa began experiencing severe Power Incontinence. Fearing that she would be banished as a youkai imposter, he had Rinnosuke care for Marisa more and more frequently to hide her abilities from the Village residents, until Marisa eventually realises that she is a Magician. She wanted to explore her abilites while he wanted her to hide them, and subsequently Marisa ran away to live in the Forest of Magic. Mister Kirisame is still bitter over his beloved daughter leaving him and has mostly stricken her from his life, but part of him still yearns for those few happy years.

Mima, meanwhile, thinks that her creation contains some potential after all and offers to train her, but after the ghost is on the receiving end of one too many beatings from Reimu Marisa decides she is too good for her and returns to her solitary training mixed with bouts of kleptomania, leading to the witch we know.

Kogasa will surpass Yukari in hax one day.
think about it. She went from a weak stage 2 boss to an EX-Midboss with no warning at all. If power comes with age and training for a Youkai, this could mean that the Umbrella will be able to get power boosts right out of no where to the point where she can go toe-to-toe with Goku.

Alice is also an alchemist.
All that gunpowder she stuffs her dolls with has to come from somewhere. Given that canonically Alice tends to keep herself isolated from others, she probably makes the doll-making materials (gunpowder included) herself.
 * According to Wild and Horned Hermit, magicians in general tend to deal with things like arsenic and quicksilver. This is probably true, other than the implication that this would make Alice unusual.

Kasen broke Hell
She looked at the operating of the Hell of Blazing Fires and thought: "This much gratuitous suffering existing in the world is wrong. I shall do something about it!" Then she punched Hell so hard that it broke, and also her arm exploded, or something similar.

Thus why the shinigami is mad at her, and why she is concerned with the leakage of evil spirits out of Hell, and why considers herself a 'great villain', but also feels people ought to be grateful to her.

Kasen is Moses
She's got the horns. She's a hermit. She's all over laws and morality. She's Moses.

Moeses.
 * Alternately, Sanae could be Moeses, considering "The day the Sea split" and how she talks about losing the power of miracles. Moses split a friggin' Sea too, and that's a miracle!

The next Gaiden Game will be based around a jurisdictional pissing contest between Reimu and Sanae
One's pro-extermination, the other would rather throw a tea party with the Youkai. It's not a stretch to say they'd eventually get fed up with each other and eventually draw lines in the sand, then start arguing over where they should be and make everyone nearby pick a side. In theme with this, the game will have a story for each side and team elements, whether is's Imperishable Night style tag teams, Phantasmagoria competitive shooting with team members replacing multiple hitpoints, or a third-party SRPG or tag-team fighter.

Meiling is the creator of Gensoukyou.
Think about it. "Team Shanghai Alice". Meiling's theme song is "Shanghai Alice of Meiji 17". What if Meiling is the "Shanghai Alice" of the title? Maribel may be a character created by Meiling and everything that she dreams is actually created by Meiling's imagination, which all the girls being avatars of people she know, and, of course, our lazy gatekeeper being an Author Avatar.

Lily White / Lily Black is undergoing something similar to The Three Faces of Eve.
Both "Lily White" and "Lily Black" are unstable personalities that are repressing a third personality locked deep within Lily's mind after a particularly traumatic experience.
 * According to Touhoumon, the third form is Daiyousei. Just putting that out there.

The Danmaku rules work on the same principle as Magic's Golden Rule
...That is, where the rules as written and a character's powers and objectives conflict, the character's intentions win out. This is why Phantasmagoria of Flower View has different gameplay - both characters in each clash see themselves as the aggressor, so they compete head-to-head (where the main games always have an aggressor (the PC) breaking ground and a defender who got in the way).

This also explains why enemies "explode" in Double Spoiler and Shoot The Bullet: once Aya's got the photos she needs, she's "won", so the magic surrounding a danmaku duel forcibly ejects the "loser" from the area.

Meira is a member of the Hakurei Clan.
She was after Reimu for the power of the Yin-Yang Orbs, right? Presumably she's smart enough not to chase powers she can't use herself, so she must be related to the Hakurei bloodline or she'd be seeking another route to power. Probably a more distant or illegitimate member, so she was ineligible to inherit the Orbs and the powers and responsibilities that go with them. She also shares (PC-98) Reimu's purple hair.
 * I'm hoping Reimu didn't know this when she assumed Meira was flirting with her.
 * Since she didn't know who Meira was, that's not likely. Or they're not very closely related; Kissing Cousins is okay in many parts of the world, including Japan.
 * I think she wants the Hakurei Yin-Yang Orb powers in order to enhance her own Orb powers.

Alice and Medicine share a common origin.
Alice's dolls all look like little blond girls with blue eyes, wearing red ribbons in their hair. Medicine fits this description. The most obvious explanation is that Medicine is a forgotten one of Alice's dolls, perhaps one of the ones the player character encountered and shot down way back in Mystic Square, but that's way too straightforward for WMG.

My proposal, then, is that Alice's dolls have a certain look because that's just how she learned how to do them, from some unknown mentor who had the same skill, and Medicine originally belonged to that person.

Komachi is making an example of ‘em!
The reason why Komachi demands the deceased pay all their ‘money’ when crossing the Sanzu; the money represents all the people who miss them, by given away all the money the deceased loses their knowledge of those people and is freed from any lingering wish to remain with them on earth despite being dead. Those who cannot bring themselves to accept their need to leave their loved ones behind bring deep regrets with them across the river and their hesitation would surely be seen by the Yama, who would sentence them time in one of the lesser hells. So Komachi tosses them overboard to be eaten by the Sansu River’s monster fish as an example to the other watching spirits. This helps discourage the majority of deceased souls from withholding pay and thus preempts a certain amount of otherwise marginally good souls from being sent to hell.

Speculation on the Touhou Vampire
Inspiration thanks to the names of two of Youmu’s spell cards; Deva Realm Sword "Displeasure of the Seven Sins" and Deva God Sword "Components of Konpaku". The information in both their translation notes boils down to:

1. In Taoism, the most basic properties of the soul are made up by seven “hakus” –as in Kon PAKU.

2. These seven “hakus” are balanced by three “kons”, and together the kons and hakus make up the soul.

3. The body loses its three kons just before it dies, and during that time only the hakus remain. The person becomes unstable during this time due to a lack of the reason and balance that the kons provide.

4. Despite being despised, the seven hakus or “Seven Sins” are important base components of the soul and no one could live without them.

Now my lovely long idea…

Vampires drain a person’s three kons from their blood to retain their own balance, as they themselves lost their original Kons when they became vampires. They have nothing but their strengthening hakus left in their body, which grant immense physical abilities, but which will override their sense of self if not balanced by kons. Therefore, a vampire who fails to drink human blood regularly and replenish their kons will become an uncontrollable and blood thirsty killer. Or maybe just plain insane.

So strong is a vampire’s haku that they will eventually convert any kons into hakus as well, and the stronger the hakus the quicker the conversion.

Changing someone into a vampire can be accomplished by a vampire draining a human of their blood and kons, and then replacing both with a certain amount of their own hakus. The amount depends on the mental strength of the victim as well as the strength of the vampire; too many hakus in a weak person will turn them into mindless ghouls incapable of making room for any balancing kons, but still thirsting for them; while taking too many hakus out of a vampire will reduce or overrun their ability to move their body, usually only momentary, but sometimes permanently, thus making hunting and personal protection impossible and opening that vampire to attack.

Vampire conversion has the dual purposes of allowing vampire reproduction and temporarily reducing the potency of the vampire’s haku, thereby decreasing the need to acquire and balance it with human kons and so also acting as a stress reliever for the powerful vampire who is forced to drink copious amounts of blood so as to keep their hakus and mental abilities balanced.

-It's assumed that because many of their existences are on the verge of dissipating, it makes it difficult for them to act under sunlight.-Perfect Memento, The Embodiments of Spirit 気質の具現 : Phantoms 幽霊

-Although both "Kon" (魂) and "Paku" (魄) are "soul", their elements are different. "Kon" stands for a mental soul, which is separated from a body as soon as human dies and ascends to Heaven; "Paku" is a physical soul, which remains in the body a few days and goes back to the Earth. In this case, "Kon" is Youmu's phantom half, and "Paku" is the human half.- funfacts from Konpaku Youmu’s Profile Page at the Touhou wik

In light of the above, phantoms are pure ‘kon’, but the kon that can be born in plants, animals and humans rather than the kon that can only be born or reincarnated into a human. All kon is basically same besides that, thus why ghosts (the soul or ‘kon’ of a human who cannot or does not want to realize that they are dead) and phantoms (which are also ‘kon’ and may be spawned from a dead body, or simply born as a free floating spirit) are often mistaken for each other.

A kon without a body to shelter and nurture it will be quicker to dissipate then a kon housed in a body of some sort, this is due to their very precarious form of existence.

In this way, a vampire’s kon (which, while it might be housed in a body, is still under constant attack from the vampire’s leech-like haku) will be weakened when exposed to direct sun light, and thus the vampire thirst and need for balance will increase and their ability to fully control their bodies shall weaken.

Because the vampire is a kind of youkai, it is most affected by spiritual attacks, and because vampires rely on a very delicate balance of kon and haku, any spiritual attacks have a tendency to harm them more than they would other youkai. Hence the vampire’s long list of odd weaknesses, in most cases it is the faith humans put into these odd talismans or ideas that harms the vampire, not the items or ideas themselves. The humans make it real.

Water, especially clear running water, is considered by many cultures to be a purifying substance, so vampires cannot go out in the rain and have great trouble crossing rivers. (Some phantoms and ghosts might have similar reluctance in regards to rivers, most likely due to them unconsciously ‘seeing’ the similarities between a normal river and the Sanzu river, which is path to the Yama and also the representation of forgetting one’s time in life.)

Sunlight is often connected to human safety, life, and the death of the night and all devils that dwell in it, making a vampire’s original weakness to it even stronger.

Other cultural items, such as roasted beans, sardine heads, and broken holly branches, gain their power from that culture’s belief in them, thus what harms a vampire in England may be of no consequence to a vampire of Japan or Africa.


 * This is easily the best wild guess on this page. Wow.

Reimu is a Saiyan
Or at least of Saiyan descent. That's where all her power really comes from.

The thing that Utsuho consumed wasn't a sun god.
It was Deathwing. This explains why she turns into an Omnicidal Maniac as soon as she gains these powers. Also, Deathwing was trapped underground for quite some time, so it makes sense here, too. That and her theme syncs with the Cataclysm opening cinematic.

The Scarlet Sisters are Danes.

 * Factoid 1: The Order of the Elephant is headed by the Queen of Denmark. Included among Knights of the Elephant are the Emperor and Empress of Japan and their sons.
 * Factoid 2: Norse paganism was largely practiced in the Scandanavian region, which includes Denmark. Among notable items within Norse paganism are Gungnir and Laevatein.
 * Factoid 3: The Flag of Denmark is a white cross on a red background.

Mima is Returning for real in Ten Desires.
In Youmu's scenario, Yuyuko mentions that she wagers "some troublesome individual will make a return." Also, this game's focus seems to be on spirits, monsters, ghosts, and etc.

Erm, yeah. That's pretty much all I got. Still, it would be awesome. On the other hand, Myouren Temple might point at Byakuren (her brother's name is Myouren), so it could be about Shinki too.
 * The prologue ends with the Big Bad awaiting their resurrection and plotting vengeance. Mima certainly needs to resurrect, and has had vengeance as her motivation since her first appearance.
 * In Reimu's Scenario, Yuyuko said that these are not ghosts but spirits - Mima once said something similar about herself.
 * ...and all of this is officially Jossed now, as the person who's at the center of this incident is someone else entirely.

Suwako wants Sanae to become a goddess.
She is particularly insistent in UFO to have her defeat youkai, which arguably is the work of a shrine maiden... However, she could have been testing her abilities. In Hisoutensoku, she pretty much tells her that she's basically a god. And now in Ten Desires she seems to be looking to have the god spirits under her command.
 * However Sanae is happy listening to Kanako, so this only has the side-effect of having more confidence with herself.

Every character in Ten Desires will have a different goal than the others.
Based on nothing more than the fact that 4 playable characters + 6 boss characters = 10 desires. How the EX-boss fits into this, I have no idea.
 * The playable characters could be the stage four bosses

Ten Desires name comes from...
The game will contain ten things fans have been begging ZUN to do.
 * Youmu has returned as a playable character.
 * Which subsequently leads to having more than 3 playable characters.
 * Spell practice is back.
 * Mima returns?
 * Supposedly it will be easier than most.
 * Other characters from past games will be back.
 * Rinnosuke will appear in the game.
 * A fan theory will be confirmed.
 * We will get another Phantasm mode.
 * At least one shipping war will end.
 * It might be a reference to the ten commandments.

Sakuya is not a lunarian
she's Akemi Homura.

Utsuho Reiuji will received alot of flak after the events of the March 11, 2011 Japan Earthquake ...
If the Dai-ichi nuclear power plant does become the next Chernobyl, there would be a huge chance real people would distance and disassociate themselves away from our beloved Utsuho. Why? Because of the power she personify. When that disaster happens, the least thing people would want to see is a simple minded hell raven powered by nuclear energy.
 * Case in point. When thisTroper saw a video clip of a Japanese town with its tsunami warning klaxons wailing, the first that came to thisTroper's head was Utsuho. How much more if the disaster was nuclear!
 * Shouldn't Tenshi be blamed also for the Earthquake AND Tsunami?
 * Clearly Tenshi caused the earthquake. But the tsunami was probably Murasa being woken up rather abruptly from her nap.
 * Earthquakes and Tsunamis are natural disasters and they can easily be associated as the works of any Shinto gods but a nuclear disaster... Zun might be compelled to drop Utsuho from the Touhou franchise completely!
 * I sincerely doubt that peer pressure of that sort will cause ZUN to drop a character, since he stated once in an interview that he makes the games because he wants to, not to please the crowd. So unless ZUN himself wants to distance himself from her, she's not going to be dropped so easily. Plus, fanon will always make stuff for her, even if canon doesn't, so she'll always have fans somewhere, keeping her in mind.
 * Utsuho ALWAYS could have been considered a controversial character, given the history of Japan with nukes. She's not one of the closest things to a villain in the setting for nothing. As it goes, the recent disaster just adds on to her controversiality. As for the earthquake and the tsunami alike, I blame Namazu aka That Unnamed Giant Catfish.
 * Coincidentally, Tenshi and Utsuho are partners in the long running 4koma series Touhou Tag Dream, which by this point in its 4th year run probably deserves its own page.
 * Actually, nuclear fusion and nuclear fission are two very different things. For one, fusion does not release radioactive waste. Fusion combines hydrogen atoms and is currently impossible for humans (but not Utsuho) to achieve. And despite that, this troper still thought of Utsuho when he heard of the disaster...

The players are the only ones that see cute girls.
To everyone else, the various youkai look like, well, youkai. Reimu/Marisa/Sanae are excluded from society because they don't mind the appearances of the youkai, either because they are insane (Marisa), are used to it (Reimu) or are just going along with everything because they were placed on the top of the youkai mountain (Sanae).
 * So the player is actually Akyuu? Because she has drawings of the characters the way we see them, and describes a number of them as looking human
 * Alternately, the player characters see through the "cute girl" disguises of the youkai—Reimu instantly recognizes Yamame as an "enemy arthropod" and asks Suika about her—but the players themselves, being ordinary nonmagical humans, do not.

Various theories on characters.

 * Reimu lives alone at the Hakurei Shrine, but she's not the only Hakurei alive. The rest of the Hakurei bloodline lives outside Gensokyo, and send their eldest daughter to manage the shrine in Gensokyo every generation as a means of safeguarding the bloodline. If the Shrine Maiden gets killed before she can have a family, they can just send in another Hakurei of the same generation to resume the duties. This way there is no actual threat of losing the entire Hakurei family to rogue youkai.
 * Marisa is more than just a pupil of Mima, she's her next incarnation. Mima taught Marisa to use magic in order to save herself some time in her return, and her disappearance from the series means that she's taken residence within Marisa. This is even hinted towards by her old theme, Vessel of Stars ~ Casket of Star. She's to serve as the vessel for Mima's return. A 'casket' for a dead 'star', as she was an important character for the first 5 or so games. With Marisa now donning a star and white bow on her hat in Fairy War, very similar to how Mima's hat appeared, it seems that she's dropping hints towards this.
 * Rumia and Alice are two halves of a whole story. The Alice that we know of the Windows series is, indeed, a human that became a youkai magician, but her name isn't originally Alice. Rumia is the original Alice. The Windows version took advantage of the aftermath of the chaos in Makai and subsequently PC-98 Alice's return with the Grimoire to steal the book from the defeated young demon girl and steal her identity, sealing her memories and most of her power with a magic amulet. Being the daughter of the old ruler of Pandemonium, naturally Rumia would have power over darkness. That's all that she can manage however. The new Alice has largely used her stolen power to benefit herself, granting herself youkai immortality, and using the magical control she has over dolls to earn money from performances in the village.
 * Sakuya used to be a circus performer, who used that public role to assist her on her double identity as a legendary thief. Her skill with throwing knives comes from part of her act, which she practiced often to find even more unbelievable tricks she could pull off with the use of her innate ability to stop time, to keep people focused on her act. She would use their intense focus against them while she stole their possessions while time stopped, and then resumed to finish the trick. Her servitude to Remilia began when she marked her during a performance, but the vampire noticed her theft and had Sakuya arrested. Rather than have her face whatever punishment she would have normally, she took Sakuya as a servant, a role that she has since come to prefer over her old life.
 * Yukari isn't actually a youkai, she's really asleep all the time. Her power over boundaries allows her to fudge the Border of Dream and Reality in order to act in the real world. She does this to protect her real body, in case anyone should manage to circumvent her power and defeat her, they can't force her to do anything. Her flightyness and odd behaviour comes from the fact that she's essentially living with the consideration of dream logic as the real thing, and her odd attacks in the fighting games stems from dream logic as well. With her real body in Mayohiga where no one can find it on purpose, and two shikigami protecting it, she can safely putz around all she wants without true fear of retribution.
 * Keine is actually a friend of Mokou's from her life prior to the Hourai Elixir. Kamishirasawa is only her surname for the present time as part of her plan to extend her own life to be with her friend. She uses her power to rewrite history to shift her birthdate up one year, writing herself as the child of whatever women of age she knows and retroactively integrates into their family through this. She bumps up her birth year as long as feasible, then changes to another woman as soon as possible. She uses her role as a teacher to find prospective future 'mothers' for herself, as it allows her to get close enough to observe prospective girls lives before she makes a choice, condition them to her liking, or even outright propose they become part of her plan.
 * Reisen is an ex-member of some kind of Lunarian Special Forces team, which her powers made her a prime candidate for. Her usage of explosive bullet like shots is part of her skillset, and it works alongside her natural abilities. She would be perfect for infiltration, sabotage and even assassination, as anyone that saw her could likely be convinced it was an illusion, or otherwise driven insane by her manipulation. Reisen took an issue with this life at some point, and ran away.
 * This one is canon, more or less

Yoshika Miyako is Meiling's dead sister
She has Chinese origins (She's a Jiang-shi, or in other words, a chinese zombie), and that hat with a star.

Yoshika Miyako's stretch exercises are why there are "fast zombies" in movies lately.
Just as Romero's works influenced the Jiangshi existence; Miyako choosing to believe she can change the nature of her very existence is having a reverse effect on said zombie legends in the outside world. (The very fact that Miyako is aware of outside trends is...interesting.)

Mokou has always had the ability to manipulate fire
Reimu has the ability to "float", and Sakuya can manipulate time and space, so there's a possibility that some humans can be born with an innate magical ability, albeit an extremely rare possibility outside of Gensokyo. Granted, fire being fire, she probably had little to no control over it besides causing things to spontaneously combust (including things she didn't want to burn) until she spent centuries learning to tame it.

None of this contradicts the possibility that she might have encountered, and might have taken in power from the Phoenix, mind you (which would probably involve refining and amplifying both her fires, and her immortality).

Gensoukyou is Vault 69 from Fallout
Unnatural female to male ratio? Check. Nuclear Power? Check. Liberal use of lasers? Check. Inability to leave the setting? Check.

There is no other explanation. Gensoukyou is part of the Vault Experiment created by Vault-Tec in order to determine how people would behave on spaceship-like conditions.

There is a master manipulator behind every game since Phantasmagoria of Flower View.
All the events of the games, starting with Mountain of Faith, have been canonically connected. Kanako provided Utsuho with the Yatagarasu, triggering Subterranean Animism. Orin's panicked geyser blast also freed the Palanquin ship, triggering Undefined Fantastic Object. The unsealing of Hokkai is no doubt the source of the spirits in Ten Desires.

Wall of text time.

This Troper thus theorises that there is a manipulator, seperate from and possibly undetected by Yukari, that has guided the whole thing. He gave Kanako the means to move the Moreya Shrine into Gensokyo, thus providing a cover for his own entrance into the same. By taking advantage of her love for science and industry, he not only provided her with the Yatagarasu, but he told her where and how to deliver it. Since he helped her before, she would be quite willing to repay him in this way. Now an easily-manipulated Hell Raven has immense power, enough to free the Palanquin ship. Her antics do the job... partly. He then convinces Orin that informing her master of Okuu's insanity is a bad idea, and has her blow open a geyser to attract outside help. This frees the Palanquin and its crew, which are the ones he needed all along. He may well have been in communication with them, and may have enabled their ship for flight. He had long ago obtained the Jeweled Pagoda, and planted it at Kourindou where Nazrin would find it. All this together, he now had the means to get into his ultimate destination, Makai.

But! Things began to break down at the last minute. While he anticipated, indeed planned, the release of the Palanquin, he did not anticipate Nue's release. He had always accounted for Reimu and Marisa in his operations, but with Nue and her seeds of non-identification in play, the heroines felt more pressured than ever, and thus fought harder. They very nearly derailed his plans, forcing him to improvise. He intercepted Nue, and enlisted her help. Possibly via force. Nue then distracts the heroines via the Extra stage, while he slips into Hokkai. In now-unsealed Makai, he can enlist the help of old PC-98 bosses for whatever devious plans he may have. The spirits in Ten Desires? A side-affect of Hokkai's unsealing that may cause him even more touble down the line.

Convoluted, yes, but after Silent Sinner in Blue, and Yukari's brilliant masterplay, I have no doubt that this is not only a logical possibility, but a workable one. If this, or anything like it, is accurate, then we have the perfect setup for a beautiful endgame storyline in a later game.


 * And now, with the Touhou 13 demo out, this theory has additional support, if anything else. Simply, Yuyuko has started to suspect our hidden chessmaster (Told by Yukari over a dish of sake?), and has decided to send our heroines to either a)Determine his plans, or b)Stop them entirely. As such, she taught the heroines how to fight from beyond death (namely, the Trance mechanic from 13, a player version of Yuyuko's Ressurection Butterfly from 7), and directed them to a likely location. This explains both why she was the first boss, and explains her seemingly random hint to the graveyard. Fast forward to Stage 3. Our opponent, Miyako Yoshika, is a Jiang-shi, a Chinese vampire/zombie. She was revived and is controlled by the seal on her head. Now, the nature of Gensokyo's creation would leave absolutely no Chinese within when the barrier went up. The only known Chinese, Hong Meiling, is an import. Thus, noone should know how to create Jiang-shi... unless our chessmaster brought the secret with him from the outside! Thus, Yoshika and her fellow zombies are either his creations, or the creations of a subordinate. He's making his move.
 * Don't you mean "she"? There's no reason for said manipulator to not be a woman...
 * True, but given that ZUN wanted the final boss of 12 to be Byrauken's older brother (at first), there is a chance at the manipulator being male. And besides, proper English grammar requires that in the case of unknown gender, the masculine pronoun is to be used.
 * The fact that ZUN changed it shows that he doesn't want to use a male even if they're a historical figure. And most people use the singular 'they' in the case of unknown gender

The "human" characters become more powerful during every interval between games.

 * In Mystic Square, Alice is a stage 3 boss, but powers herself up to become an EX boss. Two games later, she's dropped down to being a stage 3 boss again.
 * In Perfect Cherry Blossom, Yuyuko is a stage 6 boss. Imperishable Night, Phantasmagoria of Flower View, Mountain of Faith, Subterranean Animism, and Undefined Fantastic Object happen, and when Yuyuko shows up as a boss again in Ten Desires, she's fallen all the way down to being a stage one boss.
 * More than likely, Youmu has it right; Yuyuko only fights in Ten Desires because she's bored and has somewhat useful information. She has no reason to stop the heroines (except maybe Youmu if she suspects the incident to not be worth being gardener-less for a day or so), and she did the exact same thing to Youmu in Scarlet Weather Rhapsody (also in Stage 1). If she isn't fighting because she's bored, then I'd have to imagine she's doing it because she realizes that danmaku must be exchanged before information can be.
 * Reimu and Marisa are consistently both stage 4 bosses to each other. When Aya fights them in Mountain of Faith, she's a stage 4 boss to them, too, which would presumably put them all on about the same level. When Aya encounters them again in Double Spoiler, they're suddenly EX bosses.
 * Similarly, in Embodiment of Scarlet Devil, Cirno is a stage 2 boss. In the very next game she's a mere stage 1 mid-boss. By the time of Fairy Wars she's fallen so far behind that Marisa is an EX boss from her point of view.
 * Kogasa is the exception that proves the rule, in a slightly more literal sense than usual. Stage 2 boss in Undefined Fantastic Object. She's still in stage 2 now stage 3 in Ten Desires, now as the mid-boss. Aren't you surprised?

Clearly, Reimu and Marisa are steadily getting more powerful every game. Youmu can presumably be assumed to be doing the same, since she also experiences stage 1 Yuyuko in Ten Desires. Sakuya is most likely similar as well. Sanae's harder to pin down, given that she raced on ahead and became an EX mid-boss in Subterranean Animism, but that's just because she knows better than to worry about common sense.


 * Actually, Kogasa is the Stage 3 midboss, so she is actually stronger, Yuyuko wasn't even trying to stop them and probably was just bored so she was weak on purpose. Alice needs to use her grimoire to be strong and she didn't use it in her PCB battle. But that doesn't mean that Marisa and Reimu aren't getting stronger, I believe you're right, but your logic is a bit wrong.
 * ...Kogasa's appearance is so surprising that she made me lose count?

Yukari is Gensokyo's Hidden Evil Overlord. Reimu and Marisa are her Unwitting Pawns.
Gensokyo was once a haunted region of Japan, a place of total chaos caused by youkai, until it was sealed from the outside world. That was when Yukari brought down the other youkai's power and dominated the area. Some youkai began obeying her, and she gathered enough youkai to try and invade the moon. This failed, and it's likely that the youkai began losing trust in her with this bold move. Many youkai are also rebelling against her, trying to reset Gensokyo's state to a pure, uncontrolled anarchy. Reimu (and probably, her ancestors) was appointed by Yukari (knowingly to Reimu or not) to exterminate hostile youkai who threaten Yukari's power, as Yukari was too occupied always doing it by herself, or she was simply lazy. Most of the incidents are either caused by said rebellious youkai, or Yukari causing it herself behind the scenes, as a way to test Reimu/Marisa's skill.

The Scarlet Mist Incident was unlikely to be Yukari's doing (Remilia doesn't seem like someone who would obey orders). The SDM inhabitants might be a rebel group with the mansion as their base. Remilia could be a rival to Yukari, seeking to overthrow her. Spreading mist was a tactic so that the mistress could go outside during daytime. Remilia's trump card is her sister, Flandre, whom she would unleash in a desperate situation. The mist bothered Reimu/Marisa so they went out to seek the perpetrator. Yukari didn't get involved, she knew that her underlings, the two heroes, would notice a youkai causing trouble and go out to defeat them. They even defeated Flandre, who might've been released by Patchy or Sakuya on Remilia's orders after her defeat. Or, she broke out on her own and went on a rampage, Remilia's plan backfiring as her mansion was hugely damaged by her own petard.

Yuyuko's spring theft happened with Yukari canonically being involved in it. Yukari helped Yuyuko to enact her plan, but she knew that the human protagonists would eventually stop her mischief. Later, Yukari herself was confronted by the heroes. She tested their power with relatively difficult spellcards, and she was defeated. A successful test.

Imperishable Night also had Yukari involved, but on the heroes' side. She teamed up with Reimu to defeat the Lunarians. Yukari knows that Lunarians aren't to be taken lightly, so she thought Reimu might've needed her personal help this time.

Mountain of Faith is where it gets interesting. Kanako, a goddess, has decided to intervene Yukari's dictatorship. Not only did she see Gensokyo as a desolate place with no faith, but also frozen in time with no technological advancement like the rest of the world. She moved her shrine straight into Gensokyo, which probably cost much effort because of Gensokyo's strongly protected border (Maybe Yukari didn't stop it because she was sleeping at the time, or she couldn't match the power of a god). The Moriya Shrine appeared right onto Youkai Mountain, a mountain infested by youkai (as the title suggests), many of whom didn't want a stranger to take over their mountain, such as the Tengu.

In Subterranean Animism, it's said that Kanako is the one who granted Utsuho her powers, and later in Hisoutensoku, her powers are used to supply a power plant. Utsuho might've ran a little amok, or it was also part of her purpose; to destroy Yukari's pawns, who have been (unconsciously) guarding Yukari by fighting Kanako and keeping her busy. Okuu is Kanako's trump card much how Flandre was Remilia's, as mentioned earlier.

Either Yukari vs Kanako is a youkai dictator versus a zealot goddess, or Kanako is the leader of the good forces, despite being the antagonist to the so-called heroes. Of course the "heroes", Reimu and Marisa, are pawns unaware that they're aiding a behind the curtains dictatorship, rather than simply defeating dangerous youkai. They're not doing it intentionally. It's all part of her plan.

So, Kanako & Okuu were the good guys (or rather, gals) in the story, seeking to turn a wasteland filled with human eating monsters ruled by an insane Reality Warper, into a prosperous land filled with technological advancement. You, the player, stopped them.

Reimu is a descendant of the Hokuto bloodline
Her ability to "vanish from existence" is exactly the same technique Kenshiro uses to defeat the Big Bad of the series. The name of the technique is the same as Reimu's ultimate technique - Musou Tensei. It's the ultimate technique of Hokuto Shinken. Also, the Fatal K.O. theme from Hokuto no Ken 2 plays when she uses Musou Tensei in Hisoutensoku.
 * Actually, it's a remix of her theme, Mystic Oriental Love Consultation. However, it is made to sound similar to the Fatal K.O. theme, so your confusion is justified.
 * You could also call it a mix. What's missing to prove her Hokuto Relatives, would be the ability to use the powers of fallen comrades. However, it doesn't appear to me that Reimu has felt "true sadness" (the requirement to use Musou Tensei) - so she might not even be at full power.

Eirin is a giant troll and the Hourai Elixir turns you into a human-sized fairy
Think about it. Both fairies and people who have taken the Elixir regenerate on death. Why bother figuring out human immortality when there is already an immortal species?

Shikieiki is related to N
I propose that N is Shikieiki's younger brother.
 * Green hair? Check.
 * Nice Hat? Check.
 * Judging based on Black and White Morality? Check.

Alice Margatroid and PC-98 Alice aren't the same person.
Just the facts: They look completely diffrent, PC-98 Alice' Last Name was never mentioned. Also PC-98 Alice is definitly a resident of Makai, not the forest of magic. The wouldn't be the only Touhou characters with overlapping names. (There are two Reisens) And it wouldn't be the only character using another one's theme. (Hatate uses Aya's theme from Mo F). I also think ZUN never implied that Alice Margatroid is from PC-98. Fanon just assumed that because of the name.
 * But in Hisoutensoku, one of Alice Margatroid's battle themes is "The Grimoire of Alice" aka the theme of Ex-Alice from Mystic Square. Plus, the locked grimoire she seems to constantly carry around resembles the one MS!Alice used in the Extra Stage.
 * That wasn't a remix made by ZUN, so it's unlikely to matter much.
 * This is pretty much denied by the fact that Alice clearly states in Perfect Cherry Blossom that she remembers Reimu ("Long time no see"), even if Reimu doesn't remember her. Why WOULD Reimu remember her? To Reimu, Alice was just another person in Makai she had to beat down. Even if she came back in her wonderland much more powerful, Reimu's defeated GODS before, so why should she care? YEARS probably passed between Perfect Cherry Blossom and Mystic Square. Alice, on the other hand, got her butt kicked twice by Reimu (and possibly Marisa) and no doubt held Reimu in her mind for all those years. Mystic Square Alice isn't given any backstory, only that she happened to be in Makai and saw fit to defend it. For all we know she could have been a human, grown up, and then became a magician youkai, migrating out of Makai and into the Forest of Magic. It IS possible to go in and out of Makai, as we see in Mystic Square and Undefined Fantastic Object.

Daiyousei is Yuma
Seriously, just look at her.
 * What about Kisume instead?

Youki Konpaku will make a appearance in Ten Desires.
Yuyuko sends the party in the right direction, so this might be possible.
 * That theory has been Jossed, I'm afraid.

Sakuya will be a boss in Ten Desires
She's pretty much going to pull what Reimu/Marisa did in Imperishable Night and investigate herself.
 * Jossed as well, sadly.

Sakuya is a Belmont
Following the theory of Sakuya being a former vampire hunter who was defeated by Remilia, The Belmonts throughout the series had a watch that stops time as one of their weapons. Since her real name is not known, she may well be an unknown Belmont whose story was never told.
 * Knives are also a very common subweapon.
 * This also means that her possible connection to Lunarians the can be explained by her involvement in the battle of 1999, since that involves Dracula's Castle being sealed in a solar eclipse.

Sakuya really DOESN'T wear pads. She just used her powers to create that effect.
Here's a bit of Fridge Brilliance. The controversy over Sakuya's pads all started because she had a practically flat chest in one game, but a larger one in the subsequent game. But keep in mind that Sakuya has the ability to manipulate time. She's even demonstrated the ability to accelerate time when she caused bamboo flowers to bloom instantly, when normally they would've taken 60 years to do so. Thus, she could've simply accelerated time on her chest to cause her breasts to grow.
 * That's a recipe for saggy, wrinkled breasts. Watch Slayers to find out more.

Shingyouku is the manifestation of the Hakurei Yin-Yang Orb
I mean, think about it. Let's assume Highly Responsive to Prayers was Reimu's first time going out to solve an incident. Shingyouku F represents 'Yin' while Shingyouku M represents 'Yang'. On top of that, the theme song is called 'The Positive and the Negative'. It's quite likely that in order to test Reimu's worthiness, the Yin-Yang Orb became animate and turned into Shingyouku. Of course, Reimu isn't skilled enough to make THAT happen again.
 * I should also note that Shingyouku's first form is a ball. Coincidence? I THINK NOT!

Koakuma is a third Scarlet sister
While Remilia locked Flandre into a basement, she made Koakuma assist Patchy in the library to keep her occupied. This way she could rule the mansion alone, while keeping her sisters below her in the SDM hierarchy. Koakuma is usually portrayed as someone overly obedient and oblivious to her master's intentions. Maybe she realizes that she's a Scarlet, but prefers to stay in the background? Maybe she doesn't know at all, by her memory being wiped out somehow, or she has a very short memory span (like Dory from Finding Nemo).

Patchouli is an Aspie
Everyone who has some basic Knowledge about Asperger's symptoms would've noticed it in her by now; her Hikikomori lifestyle, her complete devotion to gathering knowledge rather than social interaction, her formal, monotone speech, expertizing in only a few specific subjects (witchcraft) and only talking about their interests (read her SWR quotes), not showing emotions, and only wearing pajama's all day.

Like nearly all members of Myouren, Kyouko Kasodani has other non-religious reasons for joining.
She was lonely and the fact that Byakuren is nice to her is the usual draw; but she also gets to follow her affinity all day long; echoing the sutras chanted in the shrine; and get praised for it.

The Scarlet Devil Mansion is connected to Unseen University through L-Space
Because, really, why not?
 * Side WMG: Remilia's apparent ability to control fate is actually due to imported Narritivium, which is why she can never quite prevent the heroines from somehow winning.

Yukari is not quite what she seems to be
That pretty 17 year old girl? Simply an avatar, no, Yukari is something a little different. Simply put, that horrible red mesh of Eyes in her gaps? THAT'S Yukari, a small small part of her body, yes, she is an Eldritch Abomination through and through, probably the size of Gensoukyo at least, hiding in her own dimension parallel to it. When she uses gaps she's not so much teleporting as she is moving the 'avatar' to another part of her body and throwing it out there. This also answers a question that's bugged me for a while, why she didn't just gap to the Moon in S Si B and had to manipulate a border to reach it, her body doesn't reach that far.

Hong Meiling is a member of The Triads
Supporting this:
 * Her name is Hong Meiling, and she is a gatekeeper. An alternate reading for hong is the character 洪, and "gate" is men (either 門 (kanji) or 门 (simplified Chinese)). Combine the two, and you have "Hongmen," the name of an influential Chinese secret society sometimes also called "Chinese Freemasonry" and with alleged ties to the Triads.
 * She is extremely proficient in martial arts. According to legend, the Triads were founded as a resistance movement by the Five Elders of Shaolin after their monastery was destroyed by the Qing Emperor.
 * In the Hisoutensoku fighting game, one of the other characters seems to think that the Green Dragon Crescent Blade, the legendary spear of Guan Yu, would make a fitting weapon for her. Guan Yu is highly revered by both the Triads and the Hongmen.

The Yamata No Orochi exists somewhere in Gensokyo
ZUN just hasn't introduced us to him yet. The fact that he is mentioned by Rinnosuke in Chapter 26 of Curiosities of Lotus Asia as "the great many-headed demon Yamata no Orochi," which further supports my theory.
 * If that happens, said "Orochi" could end up being a she, if anything. I mean, look at Miko as an example.
 * Also, if it does happen, there would probably be a Susano'o equivalent showing up as well, and the story would likely be tied to the sword that Rinnosuke has in his shop (the Ame-no-Murakumo-no-Tsurugi), not to mention that someone may end playing the role of Kushinada-hime (the maiden described in the legend)... Hm...

Touhou 14 predictions
The stage 4 midboss of 13 will pull a Tewi and appear next game, the EX-midboss of 13 will pull a Sanae and appear playable next game, and based off the backstory of the EX-boss of 13  Because of all of this, the next game might be a Phantasmagoria type shooter.
 * So,
 * I'm okay with this.

The revival of the Ten Desires antagonists is a Moriya Shrine conspiracy.
Supposedly they woke up because Byakuren's Buddhist temple was built on top of their mausoleum... but Kanako is the one who built Byakuren the temple, and Byakuren was cutting in on her market, so to speak. Conversely the Taoists don't seem to have any interest in converting youkai, so they're Reimu's problem to deal with.
 * Temples like that are forbidden.

Sanae knew about the above Moriya plan regarding the Buddhists and Taoists; and intentionally sabotaged it to prevent a Temple War.
In her scenario; she doesn't have any reason to be there. She's mostly just wandering around. She doesn't even justify it as "Yokai Extermination" when Kyouko attacks her. She says she's just checking things out; wandering her way all the way to Miko. In actuality, she knew that her goddess wanted the two shrines to war with each other; and instead more or less peacefully (through spell card rules) suppressed the conflict before it could begin.
 * She's not even disobeying her goddess; because Kanako and Suwako don't involve her in their schemes. They didn't tell her to keep out of it.
 * Sanae is a good girl.

Because of the gathering of spirits that had occurred in Ten Desires, Kasen Ibara may make an appearance in the next game.
Considering that Toyosatomimi no Miko's presence is what caused the spirits to gather all around the mausoleum, and that Kasen Ibara. Let those two idea sink in for a bit...

Toyosatomimi no Miko is going to be a Large Ham Unknown Rival to Byakuren.
Nobody stays "evil" in Gensokyo. Toyosatomimi no Miko will have some Doctor Doom-esque monologues and lots of Say My Name shouting at Byakuren; combined with Poke the Poodle plots for the Buddhists. (Their followers, if Kyouko and Yoshika are any indication, don't have any problems with each other.) Byakuren will barely be aware Toyosatomimi no Miko even exists; or "worse", think of her as a good friend.
 * Yes, Nue said that the Buddhists were "worried" about the Taoists and said they hired Mamizou Futatsuiwa to deal with them; this was just Nue working alone and not involving the others.

One of the new characters that will appear in the coming games will be a kitsune, possibly a "nogitsune"(field fox).
Mainly to give the dislike that Mamizou Futatsuiwa has for foxes a target that is not Ran Yakumo, and also possibly to give a sort of contrast between Ran herself (who is a tenko under the service of Yukari) and a kitsune youkai who is as free to do as she pleases as most other youkai in Gensokyo...

Lily White is in fact a love goddess.
It's said that she announces spring. But, think about her name. It's Lily White. And white lily is a symbol of yuri. It can be a suggestion that she's able to bring love between Gensokyo's residents (the outbursts of spring she brings with herself can be explained by Power of Love).

Mima is the Saigyou Ayakashi sealed in a humanoid form with her memory gone.
What's the first thing Mima wants to do when she's unsealed in So EW? Kill every human /ever/. Her name means "Charming Demon," which seems very fitting considering the tree has the ability to charm people into dying. It's been said she has no idea what she is or how she got that way, so maybe she dropped the homicidal urges after forgetting. Marisa might have accidentally revived her, so she feels grateful to her.
 * Alternately, Yuuka is the tree. Or maybe both Mima and Yuuka are the tree, and are, as such, two spirits of the same being. It might explain how close they are before Mystic Square... Despite having never met before. Yuuka would be the "living" or "blooming" part of the tree, which would explain her... Violent tendencies. Mima, as I stated, would be the "spirit" part, and the "charm."

If Mima does EVER return, it'll be as a playable character in a sidegame where she goes against Byakuren and Miko
Given she wouldn't really fit a main story now and that IS how Yuuka came back. Also, Byakuren wants peace among Humans and Youkai. Miko wants to kill all Youkai. Mima wants to kill all humans, but she tends to act alone.
 * Um, where exactly does it say that Mima wants to kill all humans? I thought that she simply tends to want to mess around with Reimu, prior to her unfortunate run in with the sickness known as "Chuck Cunningham Syndrome". If anything, she would simply appear due to the fact that Miko's very presence (with causes spirits from all over to just show up) will give a reason for Mima showing up: because said presence will of actually caught Mima's attention from wherever she is, causing her to investigate.
 * Alternately, the people of the mausoleum may end up, in an attempt to get more people to join in their fight to kill all youkai, finding wherever Mima is being held, and set her free, hoping that they can ask for her aid...
 * Phantasmagoria of Flower View isn't a side game

Eirin Yagokoro may be a reincarnation of the Greek god Apollo.

 * She has a bow and arrow(archery),and she's a pharmacist (healing)
 * She even has this spell card "Apollo 13" (this refers to the space mission, though)
 * If this was true, then Kaguya would be Hera, and Mokou would be Hephaestus.
 * Which makes sense, since they're both immortals(gods) and Kaguya and Mokou hate each other.
 * It is stated that Eirin has aspects of the god Omoikane; who is associated with intelligence. (Of course, Omoikane and Apollo could be aspects of the same being.)

Seihou is the future of the Earth outside the barrier.
We know that for Maribel and Renko, Future Food Is Artificial. This will eventually result in all plant life but cacti becoming extinct. In desperation; mankind begged, pleaded, prayed for this one species of life besides themselves to save them. It couldn't. It was just a cactus. Mankind despaired. But within the Gensokyo Barrier, because of the dreams of man, cacti with an abundant amount of Mana started appearing. Out of compassion and self-preservation (Gensokyo needs the outside world to survive) this dream breed of cactus was sent back. Miraculously, it retained its powers and "Saboten Energy" was born.
 * Just As Planned by Yukari, I would easily wager.
 * Rather, they're a hybrid. There was something special about the cacti in Seihou, whatever killed off life wasn't just mankind taking in resources and not replenishing them. Cacti were immune to whatever killed off all other plantlife and the smiles of children. Let's call it an "Illusion Drought." The Gensokyo Dream Cacti were born from mankind hoping this would save them; but they would not have survived the outside world for very long. Someone crossbred the Gensokyo stock with the Seihou stock; creating a type of mana/power that would exist in the outside world; but was terribly unstable.

A youkai will appear in a future installment. One with the power to cause gender flips in others.
Sounds strange, you say? Well, considering that this would allow ZUN to insert male characters into a game without actually doing so, stating either that "they were cured of their curse of being turned into a girl at the end of the game" or "they decided to remain as they are now, as they actually like their new form more" as their ending, with the former allowing him an excuse to draw male characters in the ending, with the possibility of an actual male character become a Player Character in the next game, and the latter allowing him to pander to the fanbase, should it be something that he feels that would work out better that way.

Alice has a very specific kind of split personality regarding her puppets.
She controls them, but they're often depicting doing things to seemingly act independent. She has trained herself not to think of herself as controlling her dolls; she merely "guides" them; and the part of her mind partitioned for the dolls takes the cue.

Gensokyo is the Dream World discussed in Yumekui Merry
And Merry is the protector of the Hakurei Barrier from the outside, while Reimu protects the outside world from the inside. The Dream Demons are actually Youkai trying to get into the outside world, and since their existence would be nullified due to the outside world's disbelief in the unnatural, they have to go in through dreams, where there is a Willing Suspension of Disbelief.

Toyosatomimi no Miko's headphones aren't actually headphones.
They're merely ear covers. Miko has the ability to hear people's desires, so she doesn't necessarily need to hear what people are saying as her powers allow her to discern their wishes anyway. The way she talks to Youmu, who lacks two of the ten desires, supports this fact as she ignores everything Youmu says, only going by the eight desires she senses from Youmu.
 * They're like blindfolds on a Blind Weaponmaster.

Soga no Tojiko is an immortal ghost.
The shikaisen did work...just not for her physical body. Normally, ectoplasmic beings quickly processed by Shinigami and sent to an afterlife unless they're tied to something. (Yuyuko is binding the Saigyou Ayakashi.) Soga no Tojiko is...unprocessable. She is thus immune to shinigami or even Rin.

Meimu is Meira.
Hear me out for a sec! Meira's original goal was to kill Reimu and steal the Hakurei powers for her own. At some point, Meira went "fuck this shit I'm taking an easier route!" and, somehow, succeeded in stealing the Hakurei powers. This caused her to change her appearance completely.

I am currently working on this very theory

Elly is a Scythe Tsukumogami.
Why else would she carry around what appears to be a horribly mutilated scythe? Even if the curve can be explained away by ZUN being unable to draw a straight line, why is it's blade sharpened the wrong way? It would also explain why she can boomerang it for no particular reason. If it's her real body, of course she can do odd things like that. Maybe her power involves telekinesis, sure, we can infer that from the floor tiles, but still. It may also explain how she blocks attacks with it. She's much more used to controlling her true body than her human disguise, right?

Cirno is evolving from a fairy into a youkai that is quite a bit more powerful -- and we've already seen an example of what kind.
From Shikieiki's talk with her in PoFV, Cirno may develop into something more than a fairy, and this appears to be happening as of Fairy Wars. But what is she becoming?

Now, from EaLND/SaBND/OSP (the Three Fairies manga), we know that fairies are nature spirits, embodying aspects of nature and reinforcing the proper growth and development of plants and natural places. They seem, in fact, to be lesser versions of gods (though in Shinto, the lines between gods, mere spirits, and youkai are pretty fuzzy to start with). Gods have the ability to divide themselves infinitely, manifesting in different places with full power.

Which brings us to this: we already know a character who embodies an aspect of nature, enhances and expands plant growth, and can divide herself into multiple bodies, and is thus the template for the power level Cirno is attaining: Kazami Yuuka.
 * In other words, Cirno will one day become as powerful as Yuuka? Wouldn't that herald the coming of the Second Ice Age that's said to occur if we mess around with nature too much? Hm...
 * The corollary of this WMG is to settle the mystery over what kind of youkai Yuuka is; she is an Ascended Fairy.
 * Either that, or a God with the manipulation of ice.
 * Which would pit her and Suwako as gods that actually hate each other, and if Cirno's power over ice becomes as such that it can overpower Kanako, then Suwako may be the only one who can stop her...

Kazami Yuuka and Lily White are friends.
Yuuka loves flowers and can control them. Lily makes flowers bloom with her cheerfulness on the start of every spring. Considering their affinity towards flowers, it's not hard to make the connection between them.
 * Alternatively Lily White lives with Yuuka to help replace dead flowers with new ones. Yuuka doesn't mind because she may need the help every now and then.

Kaguya refusing the proposal for marriage by Mokou's father held greater consequences than ZUN lets on.
All it says in Mokou's profile for the eighth game is that her father proposed to the supposed "commoner," Kaguya Houraisan, and was presented with an impossible request. Naturally, he failed the impossible request and Kaguya denied his proposal. Now, all we know beyond that was that Mokou is very angry with Kaguya and that's where the rivalry starts, but let's think about things for a second. It says in Mokou's profile that she wasn't usually allowed out of the house, implying that she was an unwanted child. Her father was an aristocrat, which means his life would have depended very heavily on what his fellows thought of him. When he found Kaguya and proposed to her, he thought she was a commoner. The fact that she demanded he complete an impossible request would have been insulting enough, but when he failed and she refused his offer that would have been the ultimate blow to his honour: being shot down by a commoner of all people. This sort of dishonour most likely wouldn't have gone over well with the man's fellow aristocrats, and his standard of living would have dropped fast. The fact that Mokou was already stated to be unwanted before he was dishonoured would mean that Mokou would have also been hit hard by this. Her father likely would take all his anger and sorrows out on her, which means Mokou could have and probably did suffer a lot of abuse as her father fell and hit rock bottom. It wouldn't be much of a stretch to assume that the man eventually committed suicide, his life in shambles, leaving Mokou alone. Who would Mokou have to blame for the abuse she received from her father and his eventual demise? Kaguya. She wouldn't have simply dishonoured Mokou's family, she would have completely destroyed her life.
 * Now that sounds like it could actually hold alot of water.

Yukari is in fact the Empress of Gensokyo.

 * She is the only official Phantasm boss in the series, placing her at a higher rank than even EX-bosses.
 * She personally led the youkai army in the First Lunar War.
 * One of her main duties is the maintaining of the Hakurei Border, which would ensure the continued existence and sovereignty of Gensokyo.
 * She is obsessed with keeping the balance of power between humans and youkai even, thus preventing civil war.
 * She has acted in controlling foreign incursions (namely the Lunarians and Celestials.)
 * She uses Reimu as a proxy to deal with Old Hell when she is forbidden by treaty to do it herself.
 * She is associated with the color purple, which for millennia has been regarded a royal color.
 * This would tie into the titles held by other characters: Kaguya is the Princess of Eientei, Toyosatomimi no Miko is a resurrected prince, and Remilia is addressed as "My Lady". Even though the last may be just out of respect for the lady of the manor, it is also the proper form of address for a noblewoman ranking from a baroness up to a marchioness.

Gensokyo is actually the island of the Amazons
It would explain the whole no men thing.

The Scarlet sisters were turned by Dio Brando
This is why they love Sakuya so much; she reminds them of "daddy."

Sakuya is Mina Harker
Dracula extended her life span, but did not fully turn her. After Jonathan's death, she became a vampire hunter, but being the proper, Victorian lady she was in her previous life, she couldn't bring herself to kill the Scarlet sisters, who were still children in her eyes. Instead she became their caretaker, choosing to keep them out of trouble rather than destroy them.

PC-98 Gensokyo is another planet (or landmass) in space and ZUN retconned it.
The Probability Space Hypervessel is a spaceship. Reimu often finds herself flying across space in order to battle youkai.

This is why the PC-98 games contain so many star/space motifs, and why ZUN won't bring anything back from the PC-98 games. And finally, this is why UFO, the throwback to the PC-98 games, contains unidentified flying objects.

Rin Satsuki was Yukari's sister and she was the one who killed Mima
Because of this, Yukari retgoned Rin Satsuki to prevent her from killing anyone else. However, this activated Rin's, which allowed her to be reincarnated as Meimu, and is secretly planning to take revenge on Yukari by killing Reimu. But she'll likely fail.

Maribel isn't Yukari
She's Mima. Upon discovering that Mima failed to cross the Sanzu River, Yukari started tearing apart the PC-98 continuity to find Mima. This caused Reimu's hair to change from purple to black, and caused the gates to Makai, Jigoku, and the Dream Worlds to be closed off. In fear, Rika and Rikako ran to the Kappas to hide, as they were fellow scientists, Meira fled back to... her samurai friends, Kana stops going outside her old house, Ellen, Chiyuri, and Yumemi all flee back to the outside world, Orange fled to the Dream World, Kurumi stayed where she was, as Yukari didn't care about her, and Yuuka's mansion was fine because Yukari didn't want to start a fight with Yuuka. Genjii and Ruukoto were taken by Yukari: Genjii because Yukari boundary-haxed Reimu the and Ruukoto to make sure Reimu does her shrine maiden duties. With nowhere to hide, Mima had Marisa use a spell that reincarnated her as a human in the outside world: Maribel. And, since all the other plot holes were tied up, Marisa's hair changed from red to blond in between So EW and Po DD because of facing the magical power of the Yin-Yang Orbs. Yes, they are that awesome.

YuugenMagan was Yukari.
One of Yukari's spellcards is named after it in one of the games. Also, it's a set of five floating eyes that look suspiciously like the ones in her gaps. If it wasn't Yukari directly, it was definitely her doing.

Keine's transformation into a hakutaku is extremely painful.
Thus the apparent anger in her extra stage appearance. She's not only protecting Mokou; she's lashing out from physical torment.

There might NOT be an official Touhou game in 2012.
Given the amount of stuff that the upcoming written work Symposium of Post-mysticism will have and the fact that it was delayed until March recently, it feels like the next actual Touhou game will be sometime in 2013. The last time such a large official written work was released was PMiSS in '06, which was a year that didn't have a Touhou game released in it (PoFV was released on 8/14/05 and MoF on 8/17/07). With the amount of apparent effort being put into this work, it probably wouldn't be wise to expect another game as well this year.

On the other hand PMiSS was released very late in '06 (12/27), so the possibility of a new Touhou game isn't that much of a stretch either. This could go either way, but since there's been at least one every year since '07 a lack of one in 2012 will likely come as a shock to quite a few. This is more of a heads-up than anything, but the next Touhou game might be coming a little later than expected.
 * And now with the news breaking of ZUN getting formally married around the day of Reitaisai, this WMG becomes even more plausible.

The plot of TH 14 will be triggered by Mamizou starting trouble with foxes.
ZUN supposedly commented that he intended the extra stage of Ten Desires to feel like a possible link to the next game, and Mamizou's profile says that her fox problem is a "story for another day". Given how every game since SA has had a plot that was indirectly caused by the events of the one before it, it seems to fit.
 * Every game since Mountain of Faith, since Kanako was behind the events of SA.

Koishi, Flandre and Mokou represent three ways emotionally troubled people react to stress and grief.
Flandre Scarlet pretty much deals with things in such an agressive way, like people would go for violence and anger to try to solve said problems. Fujiwara no Mokou is the victim of all this, some people blame everything and everybody and make themselves the victim even if the trouble they're struggle upon was caused by them in first place. Koishi Komeiji evades trouble and laughts at it, just like some troubled people that are in a profound denial and while they're through serious grief in the inside on the outside they want to look carefree and that they're happy all time and on their happy denial even being troublesome to others; all this in order to hide their grief rather than deal with it until find a solution.

Yukari used to be the goddess of the Hakurei Shrine. Mima has since taken over in her stead.
Yukari controls boundaries and borders, created Gensokyo, and placed the safety of the great boundary on the Hakurei family, who were her priests. But since Reimu has been... less than pious, Yukari has also fallen from grace and become a youkai, albeit an insanely powerful one due to her connections with the nature of Gensokyo. Her servants are youkai often portrayed as benevolent to humans, and sometimes even as helping shrines (the "beckoning cat" is in some retellings a nekomata).

In the meantime, Mima, who along with her servant Marisa was more into actually getting things done, has ascended to godhood as the "evil god of the Hakurei Shrine", and is now too busy trying to keep things working behind the scenes to put in any face time in the Windows games. Her grudge against Reimu is why Reimu remains poor, but she tries to send good things Marisa's way once in a while (though Marisa hardly notices sacred artifacts in her junk collection).


 * In Gensoukyou, Gods Need Prayer Badly is very much literal, so if Yukari was ever associated with the Hakurei Shrine itself she would have ceased to exist considering its complete dearth of worshippers. Yukari is also in the same "a youkai beyond normal youkai" category that Yuuka is in, making it even less probable that she is or was ever a god. Furthermore, Mima was never actually the spirit/god/whatever of the Hakurei Shrine, she just claimed to be such because she's an insufferable braggart and a chronic liar (something else Marisa stole from her).

Aya is the Touhou version of his girlfriend and now wedded wife
Think about it, the article says that they have known each other since Imperishable Night, and there is also a WMG of Aya being ZUN's girlfriend, especially when Aya was introduced after Imperishable Night, starting from Po FV, only to reappear many more times after in the following games.


 * Phantasmagoria of Flower View
 * Shoot the Bullet
 * Mountain of Faith
 * Scarlet Weather Rhapsody
 * Subterannean Animism
 * Double Spoiler
 * Fairy Wars

"Koakuma" does not refer to a single entity
The Scarlet Devil Mansion's library is large enough for an entire Touhou stage to take place inside it. We're never actually told how fast the characters are flying, but it does appear to be fast. On top of that, it contains enough books to keep Patchouli-who is quite literally a superhuman bookworm-occupied and with no reason to leave for over a century. No matter what you say, a library like that is going to be huge. Do you suppose it's at all easy for one person to maintain a library like that, even if they are a demon? "Koakuma" refers not to a single character but rather an entire class of them, a template for the familiars Patchy summons. This also helps explain why she just pops up out of nowhere, vanishes without a shred of story and, from what I can tell, just blows up after being defeated rather than flying off. All other stage 4 midbosses in the Windows series go on to act as bosses-with the exception of Lily White, but she is a (admittedly powerful) fairy-and even then she reappears in Touhou 9. She's certainly more powerful than the Mooks populating the stage, but not quite boss material-the rest of the SDM crew probably just see them in the same way-and Patchy, beiing Patchy, probably made no effort to stop them being expendable, seeing as she can just summon more-although she might have taken a liking to a particular one. (Do correct me if I'm wrong about the stage 4 midboss thing-I've pretty much only played PCB and IN.)

Worth mentioning I concocted this WMG after seeing this picture.


 * When ZUN acknowledged the terms "Koakuma" and "Daiyousei" he stated that they refer to a specific sub-class of youkai, and made no statement regarding the names of the particular individuals that appeared in EoSD, so this WMG is entirely plausible.

Yukari, Sakuya, and Yuuka (and possibly other uber-powerful characters) have lived several times their lifespan.

 * As we know from what Komachi said in SWR, Tenshi has lived several times her normal lifespan. Now, Yukari and Yuuka are stated to be some of Gensokyo's oldest yokai. They're also some of it's most powerful yokai. It's perfectly possible that yokai aren't immortal, just extraordinarily long lived. Yukari and Yuuka, like Tenshi, just fight off the Shinigami every time they come for her, and it may even be possible that Shikieiki has stopped sending shinigami after them because she knows they'll lose. This also might tie in to in Po FV, when Shikieiki told Yuuka she was 'a little too old': Shikieiki knew Yuuka was waaaaaay past her lifespan, but since her role was not to gather souls, she merely lectured Yuuka. For Sakuya, I believe it was stated somewhere that she's lived longer than most humans do. Rather than being ghouled like some WMG say, it's plausible that she's stronger than most Shinigami are. As for why Komachi only called out Tenshi? Only Tenshi was being all high and mighty about it, and it hit a pet peeve of Komachi's. She can tolerate people like Sakuya and Yuuka because they at least don't brag about it, it's not her job to deal with in since she's a ferrywoman shinigami anyways, and doing so would, plain and simple, just be more work.

Remilia Scarlet isn't lying when she says she's a descendant of Vlad Tepes.

 * Remilia has been alive for nearly 500 years. It is entirely possible she was born in Europe and later moved to Japan. During said time in Europe, she met Patchouli, which would explain Patchouli's relatively During this trip is when she met Meiling as she passed through China. When she met Sakuya is unknown.

Hong Meiling is a Rainbow Dragon youkai.

 * "Hong" is the name of a Chinese mythological creature that's, well, a rainbow-coloured dragon. Nearly all of Meiling's spell card and attacks (including in the fighting games) have rainbow patterns to them. Putting that together, it should be obvious what kind of youkai she is. Meiling is simply her name, while "Hong" might not be her actual name but instead, included in her name because that's her species. Translating to "Rainbow Dragon Meiling".
 * Meiling being a dragon youkai also puts her in a special category of youkai; dragons are a very big deal in Gensokyo; the god-like creature who created the realm was a dragon, who is referred to as The Dragon God. It controls the weather and many residents of Gensokyo, including the residents of the human village, pray to The Dragon God for good weather. While this WMG entry isn't claiming that Hong Meiling is this creature, if she is a dragon youkai then she must have extraordinary powers similar to The Dragon God, therefore is a far more powerful being than she lets on.

Sakuya's eyes are red in EoSD because of the red moon.
This is heavily related to the "Sakuya is a Lunarian" WMG entry; simply put, the reason why Sakuya's eyes in EoSD are a distinct red while in later installments they no longer are, is because during EoSD, the moon is red. This only strengthens the connection between Sakuya and the moon. It is also clear through the pre-battle dialogue in EoSD that Sakuya is unusually peeved, agitated, way moreso than how she behaves at any other point in time. Should be obvious where this is going: the red moon has a debilitating effect on Sakuya, she becomes more aggressive and also more relentless in battle.

The best part is, before you say "Oh, this is just an example of Early Installment Weirdness", well guess what, in the same game Sakuya's eyes turn blue during Marisa's ending slides, while during the stages (while the night, scarlet mist & red moon phase were still ongoing) her eyes were red. Why else would ZUN change this so drastically, the moment the night passes?

The following is more dubious, but it's possibly a cool touch: you fight Sakuya again as a midboss during Stage 6. This time, unlike the battles against her in the previous stage, Sakuya is now outdoors, rather than in doors, in direct contact with the light of the red moon. Sakuya's spellcard in this battle isn't the same calculated, time-stopping shenanigans she did before; this time she unleashes a barrage of bullets at you at incredible speed, full-on berserk mode. Her non-spellcard attack before this is uncharacteristically rapid as well. It's in huge contrast to every attack & spellcard she did beforehand, clearly displaying a different approach of battling. The conclusion? Sakuya being in dead-on contact with the red moon destabilizes her even more than before, which is why her attacks are so crazy and unstable here, way moreso than in the indoors stage before.

Reisen is Yukari's spy.
(Not to be confused with the manga character, "Reisen II"; this entry is about Reisen Udonge, the Imperishable Night Stage 5 boss)

Right away this WMG sounds like an uninspired Beethoven Was an Alien Spy crackpot theory, but hear me out (warning: this will be a long WMG entry, so I also tried to use a lot of spacing in order to avoid turning it into one big fat wall of text).

First, let's just go over things that're canon: Reisen is a lunar rabbit who, at some point, was trained as a special forces rabbit for the Lunarian army (most of which comprises of lunar rabbits). She was trained as more than a mere cannon fodder soldier, but she belonged to a special forces branch. Her expertise was intrigue, sabotage and assassination. Reisen also loves guns, that is a canon trait of hers (Lunarian soldiers are seen equipped with assault rifles and such in the manga, so it's safe to say most of these Lunarian rabbits are gun nuts, including of course Reisen). Befitting of a secret agent.

In the official print works, it is stated that Reisen's behaviour is quiet and mysterious, whenever she visits the human village (which she normally only does in order to shop for groceries or buy medicine at the request of Eirin). It definitely suits the personality of a secret agent, someone who "has no face". At the very least it's an expected behaviour of someone trained to become a spy/saboteur/assassin. This isn't the best canon source alluding to her inherent nature of being a natural spy, though; this is taken from Reisen's SWR profile, included with the game files: "She can change her personality completely to match her circumstances." So Reisen is very good at adjusting her personality, being kind of an enigma as to what her real personality even is.

She is a trained spy, so wouldn't you expect her to, you know, do some actual spywork? Well, from what little canon sources we have about her dubious past, Reisen "fled the moon after humans invaded it". It's likely she was simply sent on a mission instead, because since the Lunarians were at war with humanity at that exact point, the Lunarians must've started sending agents to Earth in order to, well, have them do what secret agents do against the opposing side.

Now let's venture into the actual theory. So where does Yukari fit in? If you've read some of Gensokyo's backstory, it's often repeated that long ago, there was a war between Youkai of the Earth and the Lunarians. The Youkai were led by Yukari (this is stated in canon alongside the story). The Youkai of the Earth lost the war; it's also added in the story that Yukari deliberately started the war in order to teach the Earth Youkai themselves a lesson, that they shouldn't attempt to invade the moon and instead should refrain from blind conquest, be it against any foe, such as humans. Nevertheless, it is fact that Yukari once led a war against the moon, so at one point, she was an enemy of the Lunarians (and a huge enemy at that, being the leader of the faction they're waging war with). The war is said to have happened "long ago" but Lunarians are known to have an exceptional life span, so Reisen could've been alive back then (though Lunar Rabbits are implied to have shorter lives... If Reisen is even an actual Lunar Rabbit, she could be a Lunarian pretending to be a rabbit, one of the WMG entries above has already explored this idea). Whether she was there during the war or not, it's not crazy to assume that during or after the war, Yukari would like to at least keep an eye on the moon... Plant agents directly on the moon's surface to inform Yukari of what's going on there. Reisen could be one of them.

But how does Reisen transmit information to Yukari? Lunarians probably do have technology matching Earth's human society (their rabbit army's got assault rifles for crying out loud), so Reisen could easily send information to a recipient on Earth, using technology. The problem is back in Gensokyo, where the residents still are technologically primitive for the most part, which probably includes Yukari. It should be noted that Yukari is familiar with human society so she isn't that shabby about technology the same way most of Gensokyo's inhabitants are.

Maybe they are using devices to communicate. But here's an alternative, far more interesting concept; Reisen's power is that she can manipulate wavelengths, as explained in her PoFV profile. This of course includes soundwaves. Perhaps her skill is so good that she can send soundwaves herself and talk to Yukari, from the moon. Therefore she doesn't need appliances to do it, which besides, is risky, because she could easily get caught using those things, sending information to the Earth.

But, Reisen at one point left the moon when she accompanied Kaguya and Eirin, to find refuge somewhere on Earth, once Kaguya got banned from the moon. They eventually ended up in Gensokyo. She keeps tabs on Eirin & the princess in service of Yukari.

However right away this opens a hole in the theory: "If Reisen is Yukari's agent, how does Yukari not really know where to find the perpetrators of the fake moon incident, seeing how they're in contact?" The first explanation is that Yukari already knows, but since she's tag teamed with Reimu, she's "going along for the ride" in typical Touhou fashion, the characters are easygoing even during an incident and are all about the "the journey beats the destination". She likes to see Reimu figure out the mystery, since solving incidents is Reimu's job, not Yukari's. Yukari is a support role in this adventure. Anyway, that all sounds like a rather empty Hand Wave, so here's a far better theory: Reisen is a sleeper agent. Yukari has not contacted Reisen for a long time, possibly over a century. Why? Well, the Youkai war on the moon has long passed and Yukari gradually lost interest in what was happening at the moon, so Reisen eventually stopped sending her information all that often. Instead she'd focus on blending in with the Lunarians and, as the term 'sleeping agent' implies, awaits the day Yukari calls upon her services again. Just like sleeping agents in real life.

"Fine, she's a sleeping agent, so why doesn't Reisen 'wake up' during the incident, seeing how it's a crucial moment and Yukari probably desperately needs to know some info?" That's easy to explain. While the incident is ongoing, Reisen does not know where Yukari is. Yukari is traveling with Reimu. While before, when Reisen transmitted signals to Yukari, whenever that happened Yukari must've been at a set location, awaiting Reisen's signals. Reisen is talented at sending wavelengths but she is not omniscient, so she doesn't simply know at all times where any person is and knows how to send wavelengths directly into that person's brain, unless she knows exactly where that person is. Reisen currently cannot send information to Yukari, they cannot stay in contact during the events of IN.

Until Stage 5 when Reimu & Yukari meet Reisen. This is where things get interesting (and admittedly, gets a bit wacko). Now that Yukari meets Reisen in person, they definitely could exchange info, right there and then... But they shouldn't, because you know, Eirin can't be too far away and Reisen obviously does not want to get caught by Eirin as Yukari's spy. This is where a spy's favorite method of exchanging secret information comes in: signals and code language. So following the WMG, Reisen is in cahoots with Yukari. Reisen wants to help Yukari reach Kaguya and resolve the incident, because she's in Yukari's service.

How does Reisen accomplish this? First, during the pre-battle dialogue, she simply hands out some exposition to Yukari in order to deliver information about the incident, how Eirin sealed the moon, and so on. But how does Reisen deliver this without appearing suspicious? Simple, she coats it in the typical "I'm a villain explaining my plans in detail to the hero" monologue. Eirin buys it, as anybody would; Reisen at that moment just seems to behave like a stereotypical gloating antagonist who's too forthcoming with information, in order to taunt the hero. In Eirin's case she probably thinks Reisen is just being a dumb rabbit. But this isn't all Reisen does.

At the moment, they're in a very long hallway, with an insane amount of doors. Only one of them leads to Kaguya. Ever paid attention to Reisen's sprite ingame? She is constantly making a gesture with one of her hands, making a 'pistol-shaped' hand gesture. This is how Reisen shoots danmaku bullets from her hands, but there is another use for such a hand gesture; pointing at things. Also yes, Reisen does battle Reimu & Yukari, but maybe she is doing something else during the battle, signaling to Yukari in some way. The hand gesture could've been occassionally gesturing towards which doors Yukari should/shouldn't pick once the 'battle' ends, which doors are the right/wrong ones.

But that alone doesn't hold up of course. Reisen said pre-battle: "I have sealed all the doors". If Reisen was truly loyal to Eirin and wanted to absolutely make sure her plans would go through, with no chance of Reimu & Yukari finding Eirin/Kaguya and stopping them, she would have kept ALL the doors sealed, or at least the correct door would've been more well hidden. But she didn't; it doesn't take long before Reimu says after the battle "Look, that door over there, that one isn't sealed!" Reisen immediately reacts "Oh no! I forgot to seal that one..." First of all, if this isn't an inside job, how could Reimu spot the only unsealed door so quickly, out of hundreds of doors in a virtually endless hallway?

Because Reisen sabotaged the door, either by leaving it unsealed all this time or unsealing it at some point during the night while Eirin wasn't noticing. Since there are hundreds of doors, during the battle she was also gesturing, pointing her finger towards the direction of the right door. All this in order to secretly aid Yukari (perhaps Reisen subconsciously helped Reimu figure out where the right door was too, as Reimu could've "picked up" on Reisen pointing her fingers somewhere). Her reaction when the heroes find the correct door is to act surprised, also adding "master will be mad at me". But if Reisen was truly loyal to Eirin, once Reimu spots the right door, wouldn't she deny it, saying something the likes of "o-oh, that door? No, that one is sealed". But instead she exaggeratedly goes "Oh no, you found the unsealed door!" in order to stress that indeed, that's the correct door. She also does it in order to come across as sincere to Eirin, to press the illusion that Reisen was being an extraordinarily dumb henchman, who forgot to seal the one door that definitely should've been sealed. To Eirin it would be believable since Eirin sees Reisen as her pet, so she doesn't expect her to be all that smart.

Bonus: It's canon that Reisen has worked as a spy before, in the service of Eirin. She was sent to the Lunar Capital occassionally in order to gather information. It's also stated Reisen used her telepathic abilities in order to carry out this mission, which means that the "Reisen can use her powers to communicate with someone on Earth while she's on the Moon" theory in this entry appears to be a canon ability she already has.