Under the Moon

Under the Moon is an 18+ otome game released for Windows; possibly the best known of its sub-genre. It is the second installment in a trilogy that also includes Love Drops and Ijiwaru My Master. With art by Toujou Sakana (also known for Detective Conan yaoi fanart), this game spawned a fan disk and a non-explicit PS2 port.

The heroine of Under the Moon (default name: Ashe) is the daughter of the king of the demon world. All is not well in her father's domain, however -- his power is fading and a Succession Crisis is brewing. The royal castle comes under attack and Ashe flees with her cait sith familiar (who can turn into a Winged Humanoid Bishonen catboy) and ends up getting transported to the human world. There, Ashe soon discovers that her magical powers have vanished. (Though they weren't much to speak of in the first place.)

In no time at all, Ashe and Kyle happen across Leni and Seizh, twin devil brothers with vast magical powers who have been appointed as potential successors to Ashe's father. Neither brother expresses interest in leaving their new home in the human world to take the throne, but they agree to harbor Ashe on account of an ongoing "devil hunt". Angels have declared open season on devils in the human world, leaving Ashe not only unable to defend herself, but unable to go home. Ashamed of her powerlessness, Ashe takes it upon herself to convince Leni or Seizh to become the new demon king.

Being a Visual Novel, Under the Moon naturally has Multiple Endings, the routes for which are generally grouped into two types: "pure love" and "love/hate". The "love/hate" routes are controversial for fetishizing sexual coercion and domination. It's got some Yandere action too.

Tropes used in this work include:

 * Alien Among Us: Most of the characters aren't human, but manage to blend into human society. Leni and Seizh are old hands at the Masquerade; Ashe, as a more recent transplant, is a Fish Out of Water.
 * All Men Are Rapists: No matter how sweet they may be otherwise, the power dynamics between the characters can lead the guys in this game into some really dark headspaces. Almost all of the love interests have paths in which they force themselves on the heroine.
 * Always Second Best: Seizh feels this way in regards to Leni, who always seems to beat Seizh to the things he wants.
 * Bastard Boyfriend: Love/hate routes turn most of the boys into these, though Sena is the opposite, being a bastard boyfriend only in the pure love route.
 * Cain and Abel: Leni and Seizh's Sibling Rivalry is in a sort of ceasefire state at the beginning of the game, but the resumption of open hostilities is likely.
 * The Casanova: Leni and Seizh both have instant fan clubs of schoolgirls that they pick conquests from. Leni's modus operandi is to use a girl and toss her aside without remorse, while Seizh openly maintains a Harem Seeker.
 * Cast Full of Pretty Boys: This is a dating sim for girls, it's be expected.
 * Closet Sublet: When Ashe and Kyle take up residence in the twins' apartment, Kyle is left with no choice but to use a walk-in closet for a bedroom.
 * Content Warnings: The game opens with a reminder that it is fictional and a warning not to imitate the unlawful behavior depicted within.
 * Cute Shotaro Boy: While he's in high school like the other boys, Sena might count due to his big eyes and the fact that he was voiced by a woman.
 * Dude Looks Like a Lady: Unan's looks are Angelic Beauty.
 * Emotionless Boy: Unan claims he is.
 * The Exile: Leni and Seizh were exiled from the demon world prior to the events of the game when They've come to like life in the human world though.
 * Elegant Gothic Lolita: Ashe. Well, she does wear frilly black dresses, and she's a loli if there ever was one.
 * Falling Into His Arms: Occurs early in the game between Ashe and Zero, immediately after Ashe discovers she has lost the ability to fly.
 * For Halloween I Am Going As Myself: The twins advise Kyle to use his catboy form despite the ears, tail and wings he sports, trusting that passersby will be more likely to accept him as a cosplay weirdo than a Talking Animal.
 * Forceful Kiss: Perpetrated on Ashe by the twins several times regardless of the route, and always in play in love/hate routes.
 * Forgotten First Meeting: This Romance Game staple is unusually edgy in Under the Moon.
 * Green Eyed Monster: Pretty much every love interest with love/hate paths, but applies to Leni and Seizh in all paths.
 * Leni in particular is a Crazy Jealous Guy who will flip out if Ashe interacts with men he doesn't know. In pure love routes he apologizes for it, at least.
 * Guy of My Dreams: Ashe has recurring dreams of a sad farewell with a man she doesn't recognize. It takes a while for her to realize it's more than just a dream, and indeed, she may never realize who it is (depending on the path).
 * Hello Insert Name Here: Ashe's name is changeable, and the dialogue is recorded in a way to circumvent actually saying her name except for in her own lines, which you can mute separately from the others.
 * Horny Devils: This trope is an underlying justification for a lot of the game's naughtiness - devils (and mazoku in general) have greater sexual appetites than your average human. They often live for centuries, and thus are older than they appear.
 * The Ingenue: Ashe hadn't ever been outside the castle before the events of this game, and her father is clearly interested in keeping her away from men.
 * I Want My Beloved to Be Happy: Believe it or not, . Not every time, though. Some characters he won't accept.
 * Insecure Love Interest: Seizh is very hesitant in his pure love paths, and requires a lot of convincing on the point that yes, Ashe really is in love with him.
 * Karma Meter: Impression points, gained by making dialogue choices, govern whether the guys view Ashe as a Spoiled Brat or a cutie.
 * Kiss of Death: has the ability to permanently bind another person to himself through mouth-to-mouth contact.
 * Laser Guided Amnesia: Several paths reveal that is a victim of this.
 * Long Haired Pretty Boy: Kyle and Unan.
 * Love Bubbles: Fluffy pink backgrounds drive home the unstoppable sweetness of Kyle's pure love routes.
 * The Mole:
 * Mr. Fanservice: Everyone except Ashe, pretty much.
 * Mysterious Protector: In the first half of the game, Zero appears out of nowhere to bail Ashe out of some tight spots, but disappears just as quickly.
 * No Name Given: Zero gave up his name when he left the demon world.
 * Noble Fugitive: Ashe. After losing all her powers, she has to rely on outside protection from the angels trying to kill her.
 * Our Demons Are Different: A big example of Dark Is Not Evil. Two groups, devils and monsters, live in the demon world. Devils are mostly indistinguishable from humans in appearance, while monsters have some sort of tell, like horns or wings. The demon world itself is depicted neutrally, though it has a rather harsh feudal social structure.
 * Puni Plush: The art style kind of skirts the line of this, especially in regards to Ashe and Sena.
 * Property of Love: The outcome of the good endings on love/hate paths -- Ashe ends up in happy subjection to her love interest.
 * The Proud Elite: Once you get past the cold, sarcastic exterior, Leni shows a lot of leadership potential. He's decisive, serious, and he projects authority. His bossiness toward Ashe turns outright domineering in love/hate paths, but in the pure love paths he tries to shoulder Ashe's burdens himself.
 * Real Men Hate Sugar: Leni loves ice cream, but gets embarrassed when he's caught eating some.
 * Strawberry Shorthand: The game often mentions that strawberries are Ashe's favorite food, drawing on the cuteness (and the eroticism) associated with the fruit. She smells like 'em, too.
 * Tall Dark and Snarky: Leni and Seizh.
 * Team Chef: Early on, Kyle volunteers to prepare all the meals while he and Ashe stay in the twins' apartment in order to shield Ashe, who has seldom ever entered a kitchen, from the cooking rotation.
 * Tragic Mulatto: . He's powerful enough to draw the attention of his non-human dad's people, but not powerful enough to go against their wishes even if he wanted to.
 * Using You All Along: Sena has ulterior motives for approaching Ashe.
 * Victim Falls For Rapist: One Love Martyr, coming up! Your bad boys are as good as redeemed now!
 * With Great Power Comes Great Perks: Leni and Seizh live pretty damn well in the human world. No responsibilities, a penthouse suite and girls throwing themselves at them? No wonder they don't want to go back home.
 * Yandere: Seizh seems friendly initially, but his dark side rarely stays hidden for long...and it can culminate in things like Murder the Hypotenuse or If I Can't Have You.