K-On!/YMMV

"Ritsu: It's so itchy... I want to scratch it till it breaks!"
 * And the Fandom Rejoiced: Many fans thought that when Bandai Entertainment ceased distributing DVDs in America, the first season would be it for both the English dub and the American fanbase. And then Sentai Filmworks announced they acquired the rights for the second season, complete with the English dub, and with the original English cast. The results were obvious.
 * Alternate Character Interpretation: The show itself uses this. Whenever it's a music video (whether an OP, an ED, or an in-universe imagined one), shy, timid Mio is always the most confident and imposing of the group. Possibly to reflect the fact that despite her personality, she's really the band's leader.
 * Awesomeness Withdrawal: Common reaction for people who love the series and watched it from begining to end... it's not easy to let go of a happy childhood after being allowed to go back to it one more time.
 * Covered Up: This doesn't apply to any Japanese person since it's a classic pop standard and children's song, but face it—the only reason you know about "Tsubasa o Kudasai" is either because of this show, or Evangelion: 2.0.
 * The dub replaces it with "Love Me Tender".
 * Crowning Moment of Awesome: Reserved, diligent "a-lot-has-happened-since-I-became-a-teacher" Sawa-chan's facade cracks in S2 E10 "Sensei" when people start calling Death Devil "cute" during the wedding performance. She snaps hard enough that the lights in the auditorium go out.
 * Crowning Music of Awesome: The theme song "Cagayake GIRLS!" shot up to the top of the charts right after the pilot episode aired.
 * "Fuwa Fuwa Time" as well, most likely because of the Nu-Metal part.
 * Pretty much the entire soundtrack qualifies, including most of the image songs.
 * Particular mention goes out to the cast not only singing, but also actually playing the instruments of their respective character for two songs on the second Radion Special CD.
 * Same thing happened at the live concert.
 * The second season opening theme, "GO! GO! MANIAC!", goes beyond that and manages to become the first song credited to fictional characters to reach the top of the weekly chart, while ending theme, "Listen!", also reached second place. Hokago Tea Time also manages to become the third female act to simultaneously place at the first and second spots of the weekly chart.
 * Adding to the lineup is the second season's second OP/ED set
 * Most Wonderful Sound -- "Bo boom boom boom boom!!"
 * The debut of "U&I", in season 2 episode 20. The song also counts as a Music of Heartwarming. See the lyrics and feel the love...
 * Episode 24. Not only did they write and play a song ("Tenshi ni Fureta yo!") just for Azusa, but all the graduating members get a shot at the vocals this time, and the song is so obviously about the graduation. Just so you know, this doubles as a CMOH. So hard.
 * Even after the series ended, Mio's poem about caramel sauce that everybody hated when she read it to her fanclub back in season 2 episode 7 makes a triumphant return as "Tokimeki Sugar", one of the best songs on the Houkago Tea Time II album.
 * "Honey Sweet Tea Time". Minako Kotobuki's voice is divine.
 * Ear Worm: "Don't Say Lazy", the show's first ending theme
 * The first opening theme, "Cagayake! GIRLS", is very catchy as well.
 * Any of the OP/ED songs for that matter.
 * "Gohan wa Okazu" (S2 ep20 07:40)
 * Shiny Gems
 * In-universe, even Akira considers "Fuwa Fuwa Time" to be an ear worm.
 * Ensemble Darkhorse: Along the same lines as Figwit, an unnamed background character in season 2 has caught the audience's eyes, and was dubbed Himeko Tachibana.
 * It's not just the aforementioned girl (who has also been dubbed "Girl who sits next to Yui"), many nameless background girls are garnering attention.
 * There's Ichigo in Episode 18 who, despite appearing in only a few shots in the season, is gaining fan art.
 * Averted with Satoshi, the one boy in the cast, who appears in relatively little fanart. If he is there, he's either with Ritsu or Mio. Being male may have something to do with it...
 * K-ON! is one of the only, if not the only, anime whose entire 38-student HS homeroom class has been fleshed out, with names and full character designs. Some of the classmates: right of Yui is of course Tachibana Himeko, and in front of Mio is Wakaouji Ichigo, but behind Mio is Nakajima Nobuyo, to the right of Mio is Miyamoto Akiyo, to the left of Mio is Takahashi Fuuko. Behind Ritsu is Endou Michiko, to her right is Wajima Maki, to her left Chikada Haruko. In front of Mugi is Sano Keiko, behind is Kinoshita Shizuka, to the right is Sunahara Yoshimi, to the left is Taki Eri. ALL of them have names, designs, and for several, even several lines of dialogue.
 * Unfortunately the series still manage to fall into the Only Six Faces trope. Take away the hair and any glasses, everyone looks identical (with the exception of Mugi, mainly due to their eyebrows).
 * Fandom Rivalry: Whatever you do, do NOT mention both K-On! and Haruhi Suzumiya in one sentence at websites where fans of those shows are. (Since they're mostly infested with trolls.) The odd thing is: While the creators for the manga/light novels are different, they were both made as animes by the same company, Kyoto Animation. The rivalry stems mainly from the fact that both K-On! and the second season of Haruhi were produced around the same time, and both (supposedly) suffered for it in terms of quality storytelling. Plus, there are moments in Haruhi where the characters resembled K-On!'s characters.
 * Ironically, the cover for the seventh DVD has been critized among K-On fandom for looking similar to the art style of Nichijou, KyoAni's next project...
 * Speaking of fandoms you don't want K-On! to be mentioned to - don't mention it to the Mecha fandom. They squarely blame the anime and the moe boom that would last until 2013 (with lingering effects even to this day in 2023) for a massive drop in popularity the mecha genre experienced during the 2010s. That said, most mecha fans see no problem with the show itself - it was its influence in the industry that caused major harm.
 * Fan Hater: Some people tend to accuse anyone who likes K-On! of being shallow, stupid Moe obsessed otaku who don't want substance in their anime.
 * Sadly, there isn't much to alleviate those claims if the Facebook fanpage is any indication. 60% of the comments on any given picture will be "kawaii" and many will not fail to add the "-chan" honorific when referring to any of the girls. Such generalizing is still unfair to the rest of us though.
 * Such insults shouldn't be raised at all. There's nothing wrong with liking Moe.
 * Fan-hating led to So Ra No Wo To being blind bashed as Military K-On! for having similar artwork, featuring a five girl tank crew, and music playing a strong role in the show.
 * Fan-Preferred Couple: Ritsu/Mio, and also Yui/Azusa, even though recent chapters of the manga seem to be Ship Teasing Yui/Akira and Ui/Azusa. And then there's Sawako/Mugi. The Fan Preferred Couple among the background characters is Akane/Eri.
 * I Knew It!: Because the final bonus episode had the girls getting their passport pictures taken, fans predicted that the film would be about the girls going on a trip to another country. ....guess what!
 * Les Yay: Has its own page.
 * Memetic Molester: The store clerk at the beginning of season 2 episode 19, due to his strange behavior, which many people seemed to misunderstand.
 * Memetic Mutation:
 * Un-tan! Un-tan! Un-tan! (S1 01 12:12)
 * Moe Moe~ Kyun! (S1 04 14:55)
 * "Sup, Mugi."
 * GITAH?
 * Mugi's eyebrows and Ritsu's forehead are practically characters of their own right now.
 * Joint meme with Lucky Star: "Asobitai!"
 * "Fun things are fun!"
 * "Will I become an adult when I grow up?"
 * Moe: All five girls. Yui's sister Ui qualifies too. Mio, however, deserves special mention, her Moe-ness being over-the-top even by the standards of this show, spawning a Running Gag. And when Azusa arrives, the show causes a huge moe explosion that obliterates everything within a 100-mile radius.
 * Memetic Sex Goddess: In the Anime wives poll, Mio ranked number 1# twice, and Yui and Azusa made it into the top ten in 2010 and 2012 most wanted Valentine they made it into the top three.
 * My Girl Is Not a Slut: A meta example. There was uproar about Yui and Ritsu allegedly having boyfriends, implying that their first kisses and (shock horror) maybe even their chastity has been taken. Later it was revealed that it was just Ritsu being Ritsu... playing on Mio's inherent insecurities and actually managing to pull off a pseudo-Freaky Friday Flip - Ritsu acts all girly and Mio gets all gruff and frustrated.
 * Never Live It Down: Nobody will ever let Mio forget the time she
 * Nightmare Fuel: During the sequence in the first episode of the anime, when Yui is walking down a hall with the "paranormal" clubs, a very dark and sinister-looking girl (looking similar to Enma Ai from Hell Girl) pokes her head out of a door on the left.
 * In the second season, they briefly look inside the Occult Club and see a UFO inside. Not really that spooky, but remembering the aforementioned girl from the paranormal clubs, one wonders what the deuce is going on in those rooms...
 * Being introduced to this show immediately after watching Rebuild Of Evangelion 2.22 may cause unexpected problems when "Tsubasa o Kudasai" begins to play.
 * Non Sequitur Scene:
 * When checking out the other clubs, the girls visit the Occult Club, which consists of a big, blinking UFO sitting in the middle of the club room. They consequently close the door and never talk about it again.
 * Well, we do finally see the Occult Club girls again in The Movie. Yui talks to them like the two clubs actually know each other a bit, and the Occult Club girls play a bit of a mild prank on her.
 * Also, when Mio is helping Yui study for her exam retakes, Yui falls asleep due to lack of focus. We're suddenly shown a view of them in heavy coats and a log cabin, where there's a snowstorm outside and Ritsu is seen in her own little snow fort. After she wakes up it's never mentioned again.
 * The Producer Thinks of Everything: In episode 12 season 1, when Yui enters the club room, there is a brief moment where you can see that.
 * And in episode 21 season 2, Ui can be briefly seen wearing her sister's hairpins when greeting Azusa, paving the way for the very next scene.
 * In one of the final episodes the band decides to record a cassette of their songs for posterity. The mix is included with the second album, and it includes everything that was shown to be recorded in the episode, including Ritsu talking about "rock spirit", Azusa yelling, and Tsumugi sneezing.
 * Ruined FOREVER/Yoko Oh No: Invoked in certain portions of the fandom upon learning that some of the voice actresses (Offsite links NSFW) have boyfriends, or heaven forbid, live with a man.
 * Rule 63: You better believe it! Someone actually managed to gender-flip the songs themselves!
 * Sickeningly Sweet: Mio's lyrics. Assuming she continues to write them after the School Festival we are treated to more of her saccharine creations in Episode 8 with "My Love is a Stapler".
 * Indeed, Mio probably wrote them. Yui's lyrics are carbohydrate-based, not sugar-based.
 * Sugar is a carbohydrate...
 * Viewers are treated to the first reaction to her lyrics by Ritsu and Sawa-chan in episode 5 season 1:


 * Sure, Why Not?/Ascended Fanon: Fan speculation (NSFW) led to the girl sitting next to Yui in class being referred to as Himeko Tachibana. The name itself came from an official list of class members, but no specific character was attached to the name, and while the girl in question did have a line, she was only credited as "Classmate". The character profiles in the Season 2 DVDs confirm that she's Himeko.
 * Tastes Like Diabetes: Seemingly the entire Hirasawa family. The parents are Sickeningly Sweethearts, the older sister is a lovable oaf and the younger sister is a doting Yamato Nadeshiko who is utterly obssessed with her Onee-chan (not in that kind of way, at least not in canon).
 * Not to mention Ritsu and Sawa-chan-sensei's diabetic-seisure in reaction to Mio's sincere but almost Sickeningly Sweet lyrics of "Fuwa-Fuwa Time."
 * They Wasted a Perfectly Good Plot: A common criticism of the show is that it does not focus enough on progress of the band and their music, as opposed to the more common slice of life elements. Only 4 songs are introduced in the body of the show, and the band doesn't get popular beyond their own school.
 * Woolseyism: How the French dubbed "Un-tan! Un-tan!" (Hint: Instead of going for cute noises like the other dubs, they took a glance at the animation and ran with it.)
 * For the "moe moe kyun" mantra, the English dub avoids Japanese sounds and instead goes for a spoof from The Exorcist, of all things: "The power of Cute compels you!"