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[[quoteright:200:[[VisualNovel/HigurashiWhenTheyCry http://static.tvtropes.org/pmwiki/pub/images/yangire22.jpg]]]]
[[caption-width-right:200:Rena is adorable... until [[GirlWithPsychoWeapon she gets out that cleaver]].]]
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->''"There's an old saying: Pretty girls turn heads… I break necks!"''
-->-- [[http://ladysports.com/stories/nikkistorm.htm Lady Sports]] on Nikki Storm

They are [[{{Moe}} cute, sweet, innocent, and extremely huggable]]. Incidentally, they are also [[AxCrazy varying shades of violent, unstable, and downright insane]].

Cute and Psycho is a trope that describes characters who are ''genuinely'' cute in both appearance and mannerisms but have a completely batshit crazy side. Sometimes there are distinctly different sides which may be shown equally, but other times they are mostly one or the other, the KillerRabbit displaying moments of sweetness and relative-sanity or TheCutie showing hints of a dark psychotic nature. Often there is some kind of DarkAndTroubledPast, or SplitPersonality to justify how the two aspects of the person can both be genuine, but other times no explanation is revealed.

The primary difference between this trope and the {{Yandere}} is that the Cute and Psycho character is not driven by an obsessive need to possess a friend or lover. Their motivation, if they have one, can vary immensely. They also don't necessarily have to be [[BerserkButton provoked]] to enter their Psycho-state, but can switch for reasons observers would be hard-pressed to determine.

Cute and Psycho is a SisterTrope to KillerRabbit, CreepyChild, {{Yandere}} and EnfantTerrible, and closely related to FaceOfAnAngelMindOfADemon, PsychopathicManchild and BewareTheNiceOnes, though while there is frequent overlap between these tropes being one doesn't necessarily mean a character qualifies for another. If the "cute" part isn't real, then the character is TheFakeCutie instead. Characters of this type tend to be female, though male examples do exist. TheOphelia is someone whose psychosis is part of the cute picture, rather than contrasted to it.

In some anime fandoms this character is referred to as a ''yangire'', an informal fanspeak term which is a portmanteau of ''{{yandere}}'' and ''kireru'' (a word meaning "to snap or lose one's temper"). It's also used to refer to AxCrazy versions of TheFakeCutie. Not to be confused with [[Series/KamenRiderKiva Fangire]], which is a species of monster vampire.

While there were instances of seemingly polite and attractive persons who turned out to be psychotic criminals, Administrivia/NoRealLifeExamplesPlease


[[folder:Anime & Manga]]
* Ran of ''Manga/UruseiYatsura'' is the poster child for (and likely the inspiration for all other) Cute and Psycho characters. On the outside, she's a cute redheaded girl who likes frilly clothing, baking, and flirting with Ataru. In reality, she's an embittered childhood rival of Lum who is out for some very violent revenge on the girl for well, a lot of things that aren't Lum's fault.
* ''Manga/AkameGaKill'' gives us Seryu Ubiquitous, the "Crazy Lunatic". Regularly, she's sweet around those who she doesn't consider evil. Around those that she does, of course... her personality switches over to bat-shit insane. As a matter of fact, she comes complete with [[BlackAndWhiteInsanity a twisted conception of right and wrong]].
* ''Manga/DeathNote'':
** Light Yagami, especially early in the series before ArtEvolution and CharacterDevelopment. His features do coarsen a bit the older and ''nastier'' he becomes.
** Mello. He's a downright ''pretty'' young man with a borderline [[AxCrazy psychotic]] temperament.
** Misa Amane is both Cute and Psycho and a {{Yandere}}.
** Beyond Birthday from the ''LightNovel/AnotherNote'' spinoff novel. Take [[spoiler:L's more {{Moe}} qualities]] and then add crazy-evilness into the mix.
* ''Manga/AkumaNoRiddle'' has plenty of cute lesbian assassins, most notably Otoya.
* Rio Miyaichi from ''Manga/AnaSatsujin''. She's a cute, socially awkward college student, but also a psychotic serial murderer who favors slashing her victims necks with a box-cutter.
* ''Webcomic/AxisPowersHetalia'':
** Russia is a mixture of Cute And Psycho and {{Yandere}}. He cracked for non-romantic reasons (the Bloody Sunday), has mood swings due to his [[PsychopathicManchild childlike temperament]] [[ManipulativeBastard and manipulative nature]], but his unstable side comes out ''especially'' strongly in regards to those he wants to keep close.
** Latvia has the potential to become one, having been abused so much by Russia that he comes close to snapping in the "Lily of the Valley" incident. [[BigLippedAlligatormoment It's not mentioned later.]]
* Several in ''LightNovel/ACertainMagicalIndex'' and its spinoff. From the ''Railgun'' anime, we have [[spoiler:Telestina]]. From the novels, we have [[spoiler:Anyeze]], who goes from ditzy, innocent fanservice girl to psychotic religious freak proclaiming Catholics believe that marriage with 'outsiders' is bestiality in the course of a single scene. Which is offscreen.
%%* [[spoiler:Czeslaw Meyer]] from ''LightNovel/{{Baccano}}'' -- you know, his whole reason to come to NYC...
* ''Manga/BlackButler'' has Alois Trancy. Throughout the first episode of the second season, he flips from sweet and innocent to AxCrazy so many times, it could make someone dizzy. As of his CharacterDevelopment, he move into {{Yandere}} for Claude. [[spoiler:That one backfired HORRIBLY.]]
* Hansel and Gretel, the CreepyTwins from ''Manga/BlackLagoon''. They seemed to be [[CreepyCute cute in a creepy way]], they are also a pair of AxCrazy PsychoForHire twins who kill [[InterplayOfSexAndViolence because it turns them on]] and are absolutely insane. [[spoiler: And that's to say nothing about their DarkAndTroubledPast.]]
* [[spoiler: Yukio]] from ''Manga/{{Bleach}}'' is revealed as such in chapter 466, when [[spoiler: he gleefully uses his Fullbring against Hitsugaya]] while explaining [[spoiler: how [[SelfMadeOrphan he drove his parents to commit suicide]] as revenge for their ParentalNeglect.]] And once his rival presses his BerserkButton? [[AxCrazy The guy went BATSHIT INSANE.]]
* Diva, the BigBad of ''Anime/BloodPlus'' often acts like an amusingly spacey example of TheOphelia, but she's pretty horribly evil.
* ''Manga/BungouStrayDogs'' has Q, described by Dazai as "a demented ability user" with no regard for friend or foe who amuses himself by making people hallucinate about their worst insecurities and watching them attack their friends. He's also a cute thirteen-year-old who looks like he's nine, almost constantly has a sweet smile on his face, and carries a doll half his size wherever he goes.
* ''Anime/CodeGeass'' has [[spoiler:Euphemia]], after [[spoiler:she gets accidentally Geassed into becoming a mass murderer]]. "Those of you who call yourself Japanese, I have a favor to ask. Could you all die, please?" "I was hoping you'd all just commit suicide, but you can't, can you? O.K. So, soldiers, please kill the Japanese. Kill them all." [[spoiler:Then she proceeds to grabs a submachine gun and shoot everyone.]]
** ''[[OddlyNamedSequel R2]]'' introduces Rolo, the false brother of Lelouch who is genuinely flustered by the school antics and socially awkward...because he's an assassin who has no experience with a normal life and thus defaults to "stab or shoot" when it comes to his problems. He then gets ''worse'' as he develops into a {{Yandere}} for Lelouch.
* Fear from ''LightNovel/CubeXCursedXCurious'' can become quite creepy when she decides to go fully psycho. It doesn't help that [[GirlWithPsychoWeapon she IS a weapon]] able to become all kinds of torture devices, and that this is actually her ''original'' personality.
* ''Anime/DaiMahouTouge'' is what happens when this trope is applied to an entire universe. The most prominent example is our protagonist Tanaka Punie, the princess of a CrapsaccharineWorld who does horrifying things to everyone and everything around her.
* A lot of child Contractors in ''Anime/DarkerThanBlack'' come across this way, especially the female ones, who channel a similar idea to GirlWithPsychoWeapon. Mai in the first season of the anime, and both Azuza and Bai (in a flashback) in the interquel are shown killing or maiming people horrifically while having a MoeStare expression on their faces. Maki might also count along with being a {{yandere}}. He sometimes comes off as an AdorablyPrecociousChild, but is completely psychotic and has an obsession with his leader, Amber.
* Kurumi of ''LightNovel/DateALive'' is cute and has a whimsical personality but there's a reason her codename is "Nightmare". She has to hurt or outright kill people to power her Angel, but she's also not above killing them just to amuse herself and at one point tried to kill everyone in Shido's school just to prove a point.
* ''Manga/DeadTube'' brings the ''lead girl'' Mashiro Mai, her introduction and following scenes are made to establish her as a cute girl, diligent sports girl for her swimming club, sociable to her girlfriends, cheerful smiler all around; what follows that is she being thrilled about murdering someone in cold blood, and ''demanding that it be filmed''.
* ''Manga/DeadmanWonderland'' has Shiro, the hyperactive, scatter-brained apparent ManicPixieDreamGirl who can and will rip off people's heads with her bare hands whilst smiling like a kid who's just left the sweet shop. [[spoiler:She's also the 'Red Man', the unstoppable killing machine who slaughtered Ganta's entire class at the start of the story.]]
** Toto's facial structure, body type, manner of movement, and high voice all call to mind a fairy or something similar, but he's the reigning champion of Carnival Corpse and widely regarded as battle-crazed.
* If there are types of criminals that Shinichi Kudo from ''Manga/DetectiveConan'' absolutely ''loathes'', it's either this and/or {{Yandere}}s. And there's '''no''' shortage of those in such a {{Long Runner|s}} of a series.
* Mairu and Kururi from ''LightNovel/{{Durarara}}''. Since they're [[spoiler: Izaya's little sisters]], it was obvious, though at least they're kinda sweet [[BewareTheSillyOnes until you directly mess with them]]. Other examples include [[spoiler:[[TortureTechnician Erika, Walker]] and [[DeliberatelyCuteChild Aoba.]]]]
* Nearly every Diclonius in ''Manga/ElfenLied'', with Lucy also qualifying as a {{Yandere}}.
%%* Anemone from ''Anime/EurekaSeven''. "Melt away! Melt away! ''Your brains'll melt away!''"
* Wrath from ''Anime/FullmetalAlchemist'' starts off as naively adorable, but upon being awakened... ''Yikes''.
* ''Manga/FutureDiary'':
** [[spoiler:Tsubaki Kasugano, the Sixth Diary Holder]] seems at first to be more of mix of YamatoNadeshiko and BitchInSheepsClothing when dealing with Yukki and Yuno, but then we see that her backstory [[spoiler: of orphanhood and sexual slavery]] drove her completely ''[[WoobieDestroyerOfWorlds insane]]''.
** Fifth Diary Reisuke Houjou is a cross between Cute and Psycho and TykeBomb.
** Yuno herself, typical of the postergirl for {{Yandere}} everywhere. She always has this adorable little smile on her face when she attacks people with [[AxCrazy axes]].
* Henri Claytor from ''Anime/FutureGPXCyberFormula'', who appears to be a cute and cheerful rookie racer in ''ZERO'', actually has a homicidal obsession with making Hayato pay for ruining his life. This is due to [[spoiler: his father ignoring and abandoning him after Hayato wins the championship instead of him]]. He somewhat gets better after the end of ''ZERO''.
* Parodied in ''Anime/GalaxyAngel'' with the CharacterExaggeration of Chitose, who already had some belonging issues; when the Angels left her behind or otherwise slighted her without knowing it, she went absolutely crazy with revenge, once even trying to turn them into rice and eat them. (Don't ask.)
* ''Manga/GirlsBravo'': Lisa is a rare [[ComedicSociopathy comedic example]], since [[CloudCuckoolander she's]] [[http://www.youtube.com/watch?v=w6aL3ZM_FzE loopy]], rather than [[{{yandere}} crazy.]] While she's threatened to have Kosame cap Yukinari, if he refuses her, she's far more likely to cast a summon spell ([[IneptMage provided she gets it]] ''[[MagicMisfire right]]''). Or, she'll simply have [[BattleButler her servants]] kidnap Yukinari and bring him to her.
%%* The Claw in ''Anime/GunXSword'' appears to be just a sweet old man.
* ''Franchise/{{Gundam}}'':
** Four Murasame and Rosamia Badam from ''[[Anime/MobileSuitZetaGundam Zeta Gundam]]'', both of whom were some of the earliest Cyber-Newtypes and completely insane because of it. Not evil, just frightened and confused girls with a warped sense of reality (it is not coincidence that they pilot something called the Psyco Gundam). Then ''[[Anime/MobileSuitGundamZZ Gundam ZZ]]'' introduces Elpeo Puru and her clones. Puru herself is mostly harmless but is still a {{Child Soldier|s}} with a deep-seated obsession with Judau, while her clones were all mentally conditioned to serve "Master Glemy" and were coldly classified by Zeon as equipment rather than people.
** ''Anime/MobileSuitVictoryGundam'' arguably has Katejina Loos, who doesn't look especially bad at first - she's initially rough around the edges, but fundamentally good-natured, until Chronicle gets his mitts on her (and main character Uso even states she's changed since joining Zanscare and used to be nice and kind deep down). To further complicate things, in the novels it's strongly implied she [[spoiler:underwent Cyber-Newtype treatments, which are known across the series for making those who undergo them violently unstable]].
** ''Anime/MobileSuitGundamSEEDDestiny'' has Stella Louisier, one of the Extended members of Phantom Pain, and [[{{Expy}} the series' version]] of the aforementioned Four. Adorable, childlike, happy... and a supersoldier with mental conditioning and enhanced physical skills from a complex, long-term treatment of drugs (which she can't survive without). She ends up torching half of Europe with a superweapon not out of malice... but because she was scared and had been told that the people there were "bad things" that were going to get her.
** ''[[Anime/MobileSuitGundam00 Gundam 00]]'' features [[DarkActionGirl Throne Drei's pilot]] Nena Trinity, a GenkiGirl redhead who likes to wink, mock-fight with her [[KnightTemplarBigBrother violently overprotective brother]] and fellow Throne Michael and throw up the [[VictoryPose V-sign]]. She also gives Setsuna his SacredFirstKiss (also the first kiss for the series), [[HatesBeingTouched much to his disgust]]. Exactly one episode later, Nena blows up a civilian wedding while on her way to the next mission to vent her frustration with having a hard day of work while others have fun. When asked by her brothers why she fired on civilians, Nena simply giggled and replied, "Heehee, sorry, I pressed the wrong button." In the second season, [[spoiler:she dropped the facade as Liu Mei belittled her, and Liu Mei learns the hard way about double-crossing people when Nena traps her inside her ship as it's exploding, [[EvilLaugh cackling maniacally all the while]].]]
* The title character of ''LightNovel/HaiyoreNyarkoSan'' has this naturally, since she claims to be Nyarlathotep, an insane and malicious Elder God from Creator/HPLovecraft's Franchise/CthulhuMythos, [[AFormYouAreComfortableWith in the form of a beautiful teenage girl]]. Normally she's [[GenkiGirl energetic]], outgoing, and incredibly friendly with a passion for {{Anime}} and {{Toku}}. To her enemies, however, she's an AxCrazy lunatic with [[TheresNoKillLikeOverkill no sense of restraint]] and a propensity for turning her foes into ChunkySalsa. And if [[BerserkButton you lay a finger on the guy she loves]], well, I hope you've taken out a life insurance policy.
* Ayame from ''Hanayashiki no Juunintachi''. On the outside, she looks like a normal (if tomboyish) girl, but when a pervert tries to have his way with her, [[HarmfulToMinors she proceeds to mace him with bug spray]], rearrange his face with a hammer, stab him with a box cutter, [[{{Gorn}} mess him up with scissors]]... Did we mention it's a [[TakeThatAudience shounen romance comedy manga about cooking]]?
* Ryouko Asakura in ''LightNovel/HaruhiSuzumiya'', who manages to remain Cute ''while'' being Psycho. However, [[spoiler:the human version of her from ''Disappearance'']] is your standard {{yandere}}.
* [[NightmarefuelStationAttendant Chaos]] from ''Manga/HeavensLostProperty'' is what happens when you mix AxCrazy with LoveFreak while avoiding {{Yandere}}. What you get is the creepiest Moe character in the series who wants to share her "love" with everyone.
* ''Manga/{{Hellsing}}'':
** Yumiko Takagi is a sweet, gentle soul who calls herself Yumie and ''go off her fucking gourd'' if her glasses are taken off.
** Seras Victoria manages to pull this off very well. Her standard persona is a GenkiGirl, but get her into a [[TheBerserker blood]] [[AxCrazy rage]] [[BloodLust and]] you are in for a [[UnstoppableRage REAL]] [[SlasherSmile treat.]]
* Yukino-sensei in ''Manga/HohzukiIsland'', who at one point sneaks around the school in the dark, naked, with a wooden sword, ready to beat one of the children to death. [[spoiler:Later turns out to be a subversion--yes, she's snapped and is fucking creepy, ''but'' it was because [[PoorCommunicationKills she thought one of the children]] was Cute and Psycho themselves, due to her best friend and fellow teacher turning up murdered. The kids acting very suspiciously didn't help matters. By the end of the manga, she realizes everything she thought was wrong, clears up some misconceptions about her, and then pulls a BigDamnHeroes on the ''real'' [[SadistTeacher murderous teacher.]]]]
* ''Anime/ImGonnaBeAnAngel'':
** [[spoiler:Mikael]] is usually a cute, easily agitated boy, but when under great stress and when things don't go they way he wants them, can turn into a really scary and obsessive psycho. It might caused by [[spoiler:a side effect of his halo falling off.]]
** The same can be said about [[spoiler:Silksey ]] -- very moe and doll-like but tends to smash everything apart and set on fire when enraged. Only she was a scary psycho for most of the series and again it can be argued that [[spoiler:it was mostly a side effect of her halo falling off.]]
** [[spoiler:Mama]] can turn into a very crazy witch when under too much stress.
* Yukako in ''Manga/JojosBizarreAdventure'' part 4. Initially she appeared demure shy and sweet around Koichi before quickly showing her temper and obsession. She also tends to live in her own world, which makes her dangerous.
* ''Manga/{{Jormungand}}'':
** Mildo, a twisted rival female mercenary introduced in Volume 1, who is seemingly obsessed with defeating H&C Logistics Incorporated's resident KnifeNut in hand-to-hand combat.
-->'''Mildo''': Valmet, you're all I ever think about. How you live. How you fight. How bout we beat the living shit out of each other, then I kill you. Sounds fun, eh? Kinda poetic.\\
'''Valmet''': No... not at all... you ''psycho''!
** Chinatsu, a teenage member of a two-man hit squad under orders to kill Koko. Her hobbies include cold-blooded murder, [[WrenchWench building complex mechanical torture devices]], and participating in gun battles [[GoingCommando while not wearing any underwear]].
* In ''LightNovel/{{Katanagatari}}'', (Warning, this spoils one of the best reveals of the show)
-->[[spoiler:'''Nanami:''' "My little brother kept chewing his nails, no matter how often I told him to stop. One day I ripped out his nails. He never bit his nails again." (The ninja she's torturing starts to sweat and shiver.) "It's only a story about child discipline."]]
* BigBad Byakuran from ''Manga/KatekyoHitmanReborn'', and Daisy and Bluebell of the [[spoiler:real Six Funeral Wreaths]].
* Nui Harime from ''Anime/KillLaKill''. She never lets up her playful and carefree nature, wears frilly dresses, and loves [[BreakingTheFourthWall breaking the fourth wall]]. She also gleefully recites [[spoiler: how she was responsible for killing Ryuko's father. She didn't even let up her childishness while she sunk the Rending Scissors into him in a flashback]].
* In ''Manga/LoveHina'', Motoko's sister Tsuruko is usually calm and graceful, but when Motoko makes the mistake of [[BerserkButton being... creative with the truth in front of her]], she drops that facade and out comes her AxCrazy side. Because of this and her ImplausibleFencingPowers, Motoko goes back and forth between admiring her and being scared shitless of her.
* ''Manga/MagiLabyrinthOfMagic'' gives us Kouha Ren, a seemingly typical flippant prince of the militaristic Kou Empire... right up until he takes an extreme amount of glee in utterly decimating a gang of bandits that tried to rob his carriage.
* Quattro of ''Anime/MagicalGirlLyricalNanohaStrikers'' is sweet on the front, but this is [[SmugSnake revealed to be just an appearance]].
* ''Manga/MahouSenseiNegima'':
** Tsukuyomi is like this in her earlier appearances. As of her later appearance, she become a full blown {{Yandere}}.
** Chizuru Naba seems to be a somewhat less scary example. She ''is'' genuinely kind and protective, but there are some scary layers underneath... which are PlayedForLaughs.
* Kumagawa of ''Manga/MedakaBox'' combines this with StepfordSmiler. His cheerful expression doesn't change no matter what he does; whether it's eating taiyaki (in the creepiest way possible), impaling people with giant screws, [[spoiler:or blinding them]].
* Yagami Yuu from ''Night Shift Nurses''. When she's not being a good nurse who makes her patients comfortable, she's a psychopathic, murderous nymphomaniac.
* Chloe from ''Anime/{{Noir}}'' smacks of this, [[spoiler: possibly going full-blown {{Yandere}} [[PsychoLesbian for Kirika]] by the finale]]
* Sugar, in ''Manga/OnePiece'', has the appearance of a little girl wearing a fairy-tale robe. She also has the ability to turn people into {{Living Toy}}s, neutralizing them of their powers and strength, and forcing them to have to obey anything Sugar says. She has no qualms about abusing her powers to create a slave army of toys, and if she gets angry, she will use them on her own non-toy subordinates.
* [[{{LightNovel/Overlord2012}} Overlord]] brings us two. Clementine who gleefully delights in slaughter, all the while acting in a cutesy manner, and Lupusregina Beta. The latter has the title "Sadist with a Smiling Mask" and acts like your typical GenkiGirl in front of her friends. People who spend any length of time with her can see it's all an act and even the people she's been assigned to protect are scared shitless of her. We get to see [[ColdBloodedTorture what happens]] when she's allowed to slip from her leash in the aftermath of the Battle of Carne Village. Let's just say that she earned her moniker.
* [[DysfunctionJunction A lot of characters]] from ''Manga/PandoraHearts'' are this when they're not being {{Yandere}}.
* ''Anime/{{Pokemon}}''
** Cilan probably. At first it appeared as though his burst came from his battle with [[UnknownRival Burgundy]], but in later episodes he starts slipping into this more and more. His flip-outs are mostly played for laughs, though. [[spoiler: Except for episode 69 where he flips his shit at Skyla because he didn't like her attitude problem as well as her not taking her job as a Gym Leader seriously.]]
** There is also the evil Togepi that appeared as a villain in a [[VideoGame/PokemonDiamondAndPearl Generation IV]] episode. She spends the entire episode simultaneously tormenting Ash, his friends, and Team Rocket [[ForTheEvulz for no reason other than she likes seeing people and Pokémon suffer]].
* In ''{{Manga/Pokemon Adventures}}'', when Lana enters battle mode, she will become terrible.
* ''Manga/PrivateActress'' gives us [[spoiler: Kana Juumonji]], a sweet-looking person who commits all kinds of bad actions [[spoiler: including downright murder or driving people to suicide]] while smiling angelically.
* Mari Illustrious Makinami from ''Anime/RebuildOfEvangelion 2.0''. She only appears for roughly fifteen minutes in the movie, but these fifteen minutes show [[NiceGuy a rather nice character.]] As long as she isn't in an Evangelion, that is. When fighting, Mari is absolutely crazy - it is strongly implied that she actually fights simply because ''[[BloodKnight she enjoys fighting]]''.
* PlayedForLaughs with Kafuka Fuura of ''Manga/SayonaraZetsubouSensei''. This eternally happy, cheerful girl has an [[DarkAndTroubledPast obvious and horrible past]], involving suicidal parents, relatives in jail, ostracism at school, and at least one ''exorcism'', and yet there she is, [[NightmareFuelStationAttendant enjoying life... for a value of it]]. She shows no signs yet of snapping, though people are scared of her and fear the day she does. On one occasion, her classmate, resident LittleMissSnarker Meru Otonashi, tries to "read" what Kafuka is communicating through her eyes at her prompting; she sees nothing but a red screen with the words "die die die die die killy kill die die die" and so forth, despite Kafuka never once dropping her happy appearance.
* Patti Thompson from ''Manga/SoulEater''. Cute CloudCuckooLander who exhibits odd moments of manic violence when she feels like it. Really, we should expect this, considering she grew up on the streets with her sister, surviving by mugging random people. Her 'training' suggests she's a mad, violent thing whose skill in combat has been overshadowed (as is often the case for [[EquippableAlly Weapons]]) by her extremely powerful Reaper meister.
* Kanon Nakagawa from ''Manga/TheWorldGodOnlyKnows''. She's the epitome of the sweet, adorable idol... as long as you don't get on the wrong side of her stun guns, as Keima did. Kanon and Keima's very first interaction was the latter telling the former that he doesn't know who she is. Her reaction is to taze him repeatedly.
* ''Anime/YuGiOh'' has this in a way. Yugi Muto is all timid, shy and all around nice guy, but when you threaten his friends or family, his other personality Yami Yugi takes over. Earlier in the manga, Yami Yugi sees ''no'' problem with torturing, cutting, burning, or giving a mental projection of ''death''. He UpToEleven when he activates "The Seal of Orichalcos" in the anime.
** Bakura is also this, being a nice and quiet boy who becomes psychotic and cold when taken over by "Yami Bakura".
* ''Anime/YuGiOhGX'' has happy go lucky Jaden Yuki, who also has an evil persona known as the "Supreme King". The Supreme King is ''nothing'' like Jaden. Jaden is kind, aloof and hot headed. The Supreme King is cold, tactical and ruthless.
* ''Anime/YuGiOhArcV'' has Yuya, who, like Jaden, is a nice and guy. But when he gets pushed to the brink, he gets taken over by [[spoiler: Zarc, his original form]]. When in this form, he looks demonic, and is ''completly'' insane, doing anything to win. This also applies to Yuto and Yugo, but not much for Yuri. He takes this up to a whole new level in the last few episodes, his skin becoming pale dragon scales, his feet enlarged and demonic wings on his back.

[[folder: Comic Books]]
%%* Faye from ''ComicBook/Hex11''.
* [[{{Franchise/Batman}} Harley Quinn]], a CanonImmigrant from ''WesternAnimation/BatmanTheAnimatedSeries''. Easily one of the most adorable rogues on the series. Also likes to pummel people and shoot at them for fun. In the New 52 she's much worse, just as crazy as the Joker (having been dunked in the same vat of chemicals that drove ''him'' insane), [[DependingOnTheWriter and in some cases]], even crazier.
* Rosy the Rascal from ''ComicBook/ArchieComicsSonicTheHedgehog''. She looks exactly like Classic Amy, but she's AxCrazy and [[PsychopathicManchild has the mind of a child]].
* Terra I from the 1980's "[[ComicBook/TheJudasContract Judas Contract]]" arc of [[ComicBook/TeenTitans The New Teen Titans]]. Seems like a sweet young girl; is actually a vicious and ruthless mercenary with distinct {{yandere}} traits -- she's not only sleeping with the much older mercenary/assassin who hired her, she ends up killing herself (while trying to kill him) when new Titan Jericho [[BodySurf possessed the assassin]] (who just happened to be his father) and freed the Teen Titans, making Terra believe that her lover betrayed her.
* ComicBook/ScarletWitch is a notably attractive woman with a history of suitors and admirers, but she also has a history of psychosis due to her traumatic life experiences which are exacerbated by [[RealityWarper her powers]] that [[WithGreatPowerComesGreatInsanity deteriorate her mental state at their peak]]. She is primarily responsible for the events in ''ComicBook/AvengersDisassembled'' and ''ComicBook/HouseOfM'', which respectively caused the downfall of her team and 90% of mutantkind being depowered around the world. The fact she was considered the nicest person in the team made hard for her teammates to believe her actions.
* The closest AlternateCompanyEquivalent to Harley Quinn that Marvel has is Gwen Poole, aka ''Comicbook/TheUnbelievableGwenpool''. She is adorable, sweet, cheerful, a [[TheKnightsWhoSaySquee hyper-fangirl of everything]]... but she happens to have a backstory reminiscent of Superboy-Prime's, which means she thinks all of this is fiction, so for example nameless extras are expendable in the name of the story of the hero (namely [[ItsAllAboutMe herself]]) and comicbook death is very cheap too so why ''shouldn't'' she just murder (shoot, blow up, cut to pieces etc.) the people in her way?

[[folder: Fan Fiction]]
* ''Manga/TheTruthAboutBleach'' has murderous fugitive on the run Rukia, as well as [[spoiler:Orihime]], cleverly disguised as an AlphaBitch until she [[spoiler:brutally murders two soul reaper junkies over their stash of mod soul pills]].
* A good part of the ''Webcomic/AxisPowersHetalia'' concept [=2P!Talia=] relays on all or some of the ''Alternate Coloring Characters'' fitting in this trope, even when there is next to none canon info on them aside of their looks.
* Agent Diamond, from ''FanFic/AkatsukiKittenPhoenixCorporationOverhaul'', seems to swing between this and TheFakeCutie. She is generally sweet and happy a lot of the time... she just has an extremely frightening tendency to do things like kill people adorably. There may be a FreudianExcuse behind that, as well as basic nature: [[spoiler:she "used to be" [[{{Literature/Twilight}} Renesmee Carlie Cullen]] and has only grown less human in mind since then.]]
* This happens to Sweetie Belle in ''[[FanFic/CardfightVanguardEquestriaArc Cardfight!! Vanguard - Equestria Arc]]'' after she [[spoiler: acquires PSY-Qualia]].
* Ganmed from ''Fanfic/{{Hivefled}}'', who is "surprisingly CHEERFUL for a devout member of a faith which focuses so heavily on DEATH," has shades of this. He's an upbeat, kind of [[Webcomic/{{Homestuck}} troll]] who writes bad SelfInsertFic and commits [[HumanSacrifice troll sacrifice]] without any qualms. Much of the "psycho" is DeliberateValuesDissonance, as troll culture in general is pretty violent. However, a few of the more stable cast members do suggest that a [[MoralityPet moirail]] would do him good (the implication being that he needs a stabilizing influence).
* Harry/Tristan in ''FanFic/TheJadedEyesSeries''. It's lampshaded when Tristan, [[spoiler: is in his next incarnation]], is seen and pitied by one of the slaves who thinks that that poor child being held captive by the Dark Lord... until she realizes that the child isn't being held captive and is in fact ''far worse'' than the Dark Lord.
* Light Yagami/[[SerialKillerKiller Kira]] in ''FanFic/ACharmedLife'' as {{lampshade|Hanging}}d by Ryuk.
-->'''''"You are just too damned cute, you know?"'''\\
Kira shot him a glare.\\
"I'm not cute," Light snapped petulantly.''
* [[spoiler: Zara the White Ranger]] from ''Power Rangers: Shuriken Force''. She's extremely [[CheerfulChild cheerful]] and constantly trying to [[ThePollyanna see the best]], but it's real noticeable there's something ''unhinged'' about her, especially when [[spoiler: in uniform]] and she's downright ''[[BloodKnight giddy]]'' when killing the villain's footsoldiers, and practically hysterical when angry.
* [[FluffyTheTerrible "Sweetpea"]] in ''Fanfic/ExceptItAbideInTheVine''. Out of combat, he's a LongHairedPrettyBoy GentleGiant CuddleBug and the biggest {{Woobie}} in a cast full of them. ''In'' combat, he's a giant berserker killing machine with occasional [[BlackComedyCannibalism cannibalistic tendencies]]. Although to be fair, his backstory combines the most traumatizing parts of [[Film/CaptainAmericaTheWinterSoldier the Winter Soldier's]] and [[Series/{{Firefly}} River Tam's]] pasts, so the poor guy has his reasons for being a little... eccentric.
-->"He's the Li'l Bub of giant mentally unstable cannibal cyborg assassins."
* [[https://www.fimfiction.net/story/15353/inner-glory Inner Glory]] has Shuddercry. She is Fluttershy's Dark Reflection. Dark Reflections are [[EvilTwin Evil Twins]] of the ponies of Equestria with the exact opposite personalities of their good selves, meaning Shuddercry is a violent {{Sadist}} and TheBully, who just so happens to look like [[http://static.tvtropes.org/pmwiki/pub/images/supercutelol_4746.jpg this.]]
* The MLP fic ''FanFic/HarmonyTheory'' has Charisma, a cute pink pegasus pony, who is also an ex-special forces PsychoForHire with a what is essentially a BloodKnight ''Cutie Mark''.

* The main character of ''Film/LittleSweetheart'', Thelma. She's a cute little 9-year-old girl (admittedly, with an odd resemblance to a certain ''Film/TheGoodSon'' star, though that came second) who is skilled at blackmail and stalking, and willing to [[spoiler:murder her only friend because she was going to ruin her plans.]]
%%* [[spoiler:Libbie/Boltie]] from ''Film/{{Super}}''. And ''how''.
* Becky from ''Film/DropDeadGorgeous'' is a pretty, smiling beauty queen... until someone gets in her way. Then out comes her shotgun.
* ''Film/TheMaids'' is about a couple of sisters serving as [[{{Meido}} maids]]. Their mistress loves how sweet they are and how well they serve her. Poor [[TooDumbToLive madame]] just doesn't know what they do with her clothes when she's absent. Mistress is a kind of yandere herself, just [[{{Cloudcuckoolander}} not as wicked]] as her maids.
* The hook of the TorturePorn film ''Neighbor'' is that the killer ("[[NoNameGiven The Girl]])" is an ''extremely'' ditzy, hot, and sadistic bitch.
* Annie Wilkes, as played by Creator/KathyBates in the film version of ''Literature/{{Misery}}''. Look below...
* Speaking of Kathy Bates, she plays a seemingly friendly Squirrel Lady in ''Film/RatRace''. Two women in a car stop where she (and her squirrels) are on the side of the road. She tries several times to get them to buy a squirrel, but they only want directions. She gives them very specific directions before sending them off with a paper bag marked "I <3 SQUIRRELS". The women follow the directions that send them down a very steep incline. As they plummet, they pass several signs with one word written on each: "YOU... SHOULD... HAVE... BOUGHT... A... SQUIRREL". They end up in a ravine atop a large pile of vehicles...and a skeleton holding an I <3 SQUIRRELS bag falls onto the windshield.
* Angela Baker from ''Film/SleepawayCampIIUnhappyCampers'' and ''Film/SleepawayCampIIITeenageWasteland''.
%%* Brenda Bates from ''Film/UrbanLegend''.
%%* Tracy Flick in ''Film/{{Election}}''.
* Sarah Jane [=McKinney=] in ''Film/MissNobody'' is one of the sweetest people you could possibly meet... and she thinks little of murdering people to get ahead at work.
* Lucindia from ''Hell's Highway''. Being cute makes it pretty easy to be picked up by people, who can then be brutally murdered (and, in one instance, ''raped'') ForTheEvulz.
* Belle Blake, from ''Film/{{Malavita}}'', is a cute blonde teenager who just happens to be proficient with weapons and beats the crap out of a sleazy boy with just a tennis racket. Justified as she's a Mafia daughter in hiding with her family.
* The little girl from ''Film/TheBadSeed1956''. So pretty. So polite. So well-behaved. She's also a sociopathic serial killer.
* Hayley from ''Film/HardCandy'' looks like a sweet teenager on the outside but on the inside she is [[VigilanteMan pitch]] [[MindRape black]].
* Similarly, Holly, the VillainProtagonist from ''{{Film/Pet}}'', is a pretty, artistic, and very normal young woman. [[StepfordSmiler On the outside.]]
* [[BewareTheNiceOnes Norman]] [[VillainProtagonist Bates]], as the titular psycho of ''Film/{{Psycho}}'', has very cute mannerisms and verbal tics (nibbling candy, [[GigglingVillain giggling]], stuttering, saying "sorry" and "gee") and his boy-next-door looks don't hurt anything, but none of it changes the fact that he's [[SerialKiller completely]] [[ParentalIncest bonkers]].
* The KillerRabbit of Caerbannog in ''Film/MontyPythonAndTheHolyGrail'' looks exactly the same as a regular rabbit, but it will kill anyone foolish enough to come near it without blinking.
* Unikitty from ''WesternAnimation/TheLEGOMovie''. She may look adorable, but hurt her feelings or her friends and she'll turn into an uncontrollable weapon.
* In contrast to the rest of the gangster-esq Toon Patrol, Psycho from ''Film/WhoFramedRogerRabbit'' has this sort of thing going for him.
* {{Axe Crazy}} {{Yandere}} J.D. from Film/{{Heathers}} is this. He's a boy with an attractive face, and a (seemingly) sweet personality who turns out to be all levels of bat-shit crazy.
* By ''Film/{{Deadpool 2}}'', Dopinder has become this. He's as friendly and {{Adorkable}} as ever, but has developed a disturbing enthusiasm for a hypothetical future career as a contract killer.

* Helen from Wildbow's "Literature/{{Twig}}" is often bubbly and adorable, but asking her questions can lead to being horrified and unable to unhear the answer however much you want to.
* As mentioned, Annie Wilkes from the Creator/StephenKing novel ''Literature/{{Misery}}'' is an archetypical example. A qualified nurse, she rescues the main character and her zealously favorite author, Paul Sheldon from a car crash in the middle of a blizzard and cares for him. Unfortunately, Paul later finds out that she is a psychopathic, schizophrenic SerialKiller who has no qualms against chopping off his foot with an axe and cauterizing the wound with a blowtorch if he acts up.
--> '''Annie''': [[MadnessMantra "You. Murdered. My. MISERY!!"]]
%%* Kaitlyn Wernher from ''Literature/DarkRedMind''.
%%* [[spoiler: Amy Elliott Dunne]] from ''Literature/GoneGirl'' practically defines this trope.
* In ''Literature/DoraWilkSeries'', Joshua's "[[ShesNotMyGirlfriend definitely-not-my-girlfriend]]" Laoise fits. On one hand, it seems she's genuinely sweet and nice person. On the other, she's psychically unstable, which combined with her PlayingWithFire abilities creates a rather bad mixture.
* In ''Literature/ThePaleKing'', Toni ''really'' loves her dogs.
-->"Now I'll know. If anything happens to these dogs. If they run off, or limp, or anything - I'll kill you, your family, burn your house down, and sow salt. I have nothing to live for but these dogs...But if anything gets done to these dogs I'll decide it was you and I'll sacrifice my life and freedom to destroy you and everyone you love."
* Sharon Falconer from the novel ''Literature/ElmerGantry'' and its adaptations. She cultivates the outward appearance of a successful, articulate preacher, but Elmer discovers that she is deeply disturbed. In private, she toggles different personalities, including a petulant child-like persona and a pseudo-pagan priestess.
* The Fox from Creator/SeananMcGuire's ''Literature/{{Newsflesh}}'' trilogy.
* In the novel and movie ''Literature/TheBadSeed'', Rhoda Penmark is an angelic little girl who loves her mother "Thissss much" except when she's [[spoiler: drowning a boy who won the spelling medal she wanted, setting a dim-witted man on fire because he seemed to know too much, pushing an old woman down a flight of stairs for her snow-globe]]
* Alina Galenko from the web novel ''Literature/AnimasConquest'' is a charming, pigtail-sporting neo-hippie of sorts who is absolutely not above kidnapping and terrorizing the faculty of Salva Academy.
* The Poem from ''Literature/TheDollmaker'' is a tiny and beautiful woman. She's also a horrifying sociopath.
* Kitten, the main villan in Literature/{{Price}} is a sadistic rapist, can figure out how to kill people just by looking at them and looks 14 years old.
* Phaidor in ''[[Literature/JohnCarterOfMars The Gods of Mars]]'' is described as a beautiful young girl, who is first introduced as a DistressedDamsel captured by raiders. She is also an [[LightIsNotGood White Martian princess]], belonging to a [[AlwaysChaoticEvil evil race]] of [[ImAHumanitarian cannibalistic]] [[PathOfInspiration mystics]] with [[AGodAmI god complexes]]. Her EstablishingCharacterMoment is giving a SlasherSmile to the hero when he declares he will kill all her captors, which creeps him out immensely.

[[folder:Live Action TV]]
* ''Series/{{Angel}}'': Fred's tendency to be this is never completely gone -- just dormant.
* In ''Series/GameOfThrones'', a cruel process of BreakTheCutie has brought this out in young [[LittleMissBadass Arya Stark]], whose "evening prayers" now consist of a list of enemies she intends to kill. It's illustrated at its best near the end of season three, when she calmly informs [[spoiler: ''Sandor Clegane'']] that she will [[EyeScream stick a blade through his eye]] and out the back of his skull some day. The next episode, she hammers it home by [[spoiler: catching a Frey soldier off guard with feigned cuteness and vulnerability, then repeatedly and viciously stabbing him]], all without showing the slightest remorse. Keep in mind that she's barely more than a child.
* [[spoiler:[[VillainTeleportation Alicia Baker]]]] and [[spoiler:[[ThatManIsDead Bette]] / [[StuffBlowingUp Plastique]]]] from ''Series/{{Smallville}}''.
* [[spoiler:Cassidy]] from ''Series/VeronicaMars''. Think he's the sweet, nerdy, helpless guy? Ha. More like rapist and mass-murderer. Have fun!
* Elle Bishop in ''Series/{{Heroes}}'', a cute, childish, and sociopathic woman who delights in killing, hurting, and controlling people.
* [[spoiler:The Trinity Killer]] from ''Series/{{Dexter}}''. It's also an {{inver|tedTrope}}sion; we see the dark side first. It's the "nice guy and family man" side that comes as a complete shock.
* ''Series/AllThat'''s "Ask Ashley" featured a sickeningly sweet little girl with an insanely unstable temper answer moronic viewer's mail. HilarityEnsues.
* Gem and Gemma of ''Series/PowerRangersRPM'' are a mild case. Mentally, they're about kindergarten age, and their favorite things in the whole wide world are ''[[StuffBlowingUp explosions]]''. Especially when it's the evil {{Killer Robot}}s going boom. The reason they're only a "mild" case is that they don't really want anyone hurt (though there was one time they had to be reminded that there were civilians enslaved in a factory they planned to "vaporize from sub-orbit").
* The third series of ''Series/TheThickOfIt'' introduces us to Steve Fleming, MP, who is a spectacularly unstable version of this trope; that cheerful grin, the slightly creepy compliments and the "call me Uncle Steve" attitude you see when you first meet him? Get him even slightly agitated and his AxCrazy side will come to the fore. The scary part comes when he desperately tries to suppress his insanity, swinging from StepfordSmiler to UnstoppableRage and back again so violently you wonder he doesn't give himself whiplash.
* Hooch from ''Series/{{Scrubs}}''. He's normally friendly and even charismatic, but pissing him off triggers his AxCrazy tendencies. This leads to J.D. and Turk frequently playing pranks on him to trigger his psychotic side, at one point even eating popcorn while Hooch is throwing death threats around. It becomes clearer with every appearance that the catchphrase "Hooch is crazy" thrown around by other characters is ''not'' exaggeration. After another of J.D. and Turk's pranks, he takes four people ''hostage'' and is subsequently fired from the hospital. In the very last episode of season 8, we see him in a straitjacket, proclaiming "Hooch ''is'' crazy."
* ''Series/{{Glee}}'':
** Rachel Berry definitely is a high-intensity-low-stability kind of girl, with her SeriousBusiness approach to... well... everything. It's absolutely ''adorable'' when it's not just infuriatingly annoying, especially to her fellow Glee Clubbers who just seem visibly tired of her antics at times.
** Quinn can be incredibly sweet and endearing when she's not screaming at someone or going to absolutely insane extremes [[JerkassWoobie just to feel good about herself again.]]
* In ''Series/{{Sherlock}}'', awkward, {{Adorkable}}, CampGay, Jim from IT, whose last name is [[spoiler:Moriarty]].
* Bernadette from ''Series/TheBigBangTheory'' is a mild version of this trope, usually sweet, demure, innocent, even a bit of a [[ManChild woman child]] at times, but she has a very short fuse and is extremely impatient and will go off on someone over seemingly small things and is quick to give Howard ultimatums if he has a dilemma that involves her. She also almost ''never'' stops smiling. And it's always the ''exact same'' toothy smile, even when she casually mentions the potentially weaponizeable biological specimens she's working with, or threatening someone with grievous bodily harm.
* Another mild example is Annie from ''{{Series/Community}}'': she is generally sweet and well-meaning, but minor things like a C grade or a lost pen have been known to make her crazy and/or violent for a while.
* ''Series/{{Firefly}}'s'' River is generally a cute, sweet teenage girl who is friendly and playful. She's also a [[SuperSoldier government-manufactured killing machine]] with PsychicPowers and spent three years being [[PlayingWithSyringes experimented on, trained, and surgically enhanced]] until her [[MindRape mind could no longer filter or control incoming stimuli]]. As a result she is an unstable schizophrenic with [[WaifFu ingrained martial arts and assassination training]] who often flips out without warning.
* ''Series/BuffyTheVampireSlayer'': Drusilla Keeble is soft-spoken, loves dolls and has a child-like innocence and affection for her "family" which can on occasion come across as vulnerable and sweet. She's also an [[WoobieDestroyerOfWorlds omnicidal]], certifiably insane vampiress who has on occasion been known to slit throats with her own nails. She was led to believe she was evil by Angelus who stalked, tortured and assaulted her for years until she finally turned insane and was turned into a vampire to suffer for eternity, so by this point the "psycho" part of this trope is quite understandable.
* ''Series/DoctorWho'':
** The basic characterization trait of the Fourth Doctor. He's [[TheCutie naturally extremely cute and childlike]] and knows it (exploiting it as ObfuscatingStupidity to make his enemies assume he's silly and harmless), but also an extreme NightmareFetishist and occasionally dips into BlueAndOrangeMorality. Much of the appeal of his character comes from his ability to display both the "cute" and "psycho" sides of his personality ''at the same time''.
** The Tenth Doctor is also like this. He's handsome and charming, with many eccentric quirks and a fun, bouncy personality. Underneath that, though, Ten is ''seriously'' screwed up, largely due to the trauma and guilt he carries from the Time War.
*** In the two-parter "Human Nature"/"The Family of Blood," he becomes human, adopts the identity of kindly schoolteacher "John Smith," and loses his Time Lord memories and his "psycho" side. When he finds out what he used to be, he ''does not'' want to go back to being the Doctor -- because that would mean reviving the "psycho" in him. Duty calls, though. So after becoming the Doctor again, he promptly defeats the [[VillainOfTheWeek villains of the week]] and sadistically punishes them with various AndIMustScream fates for eternity.
---->'''[[VillainOfTheWeek Son of Mine]]:''' [[TranquilFury He never raised his voice.]] That was the worst thing -- the fury of the Time Lord. And then we discovered why -- why this Doctor, who had fought with gods and demons, why he'd run away from us and hidden. He was being ''kind''.
*** In the episode "The Waters of Mars," Ten meets a woman who is fated to die, and is heartbroken that he can't save her. Without a [[MoralityPet companion]] around to keep him under control, Ten decides to save the woman, laws of time be damned -- even though he could ''destroy the spacetime continuum'' in the process. And he doesn't take long to [[JumpingOffTheSlipperySlope jump off the slippery slope]] and decide that [[ScrewTheRulesIMakeThem as the last of the Time Lords,]] ''[[ScrewTheRulesIMakeThem he]]'' [[ScrewTheRulesIMakeThem makes the rules of time]]. After declaring himself "[[AGodAmI the Time Lord Victorious]]" and starting to behave eerily like ''[[TheMaster a certain other Time Lord]]'', Ten is only jolted out of "psycho" mode after [[spoiler:the woman he tries to save kills herself in order to set time back on the right course]].
---->'''Tenth Doctor:''' There are laws of time. Once upon a time, there were people in charge of those laws. But they died. They all died. Do you know who that leaves? ''Me!'' It's taken me all these years to realize that [[ScrewTheRulesIMakeThem the laws of time are]] ''[[ScrewTheRulesIMakeThem mine]]'' [[ScrewTheRulesIMakeThem and they will obey me!]]...For a long time now, I thought I was just a survivor, but I'm not. I'm the winner. That's who I am: [[AGodAmI a Time Lord Victorious]].
** In her youth, before her HeelFaceTurn, River Song was raised as a LaserGuidedTykeBomb by an AncientConspiracy who intended her to murder the Doctor, but she was every bit as sexy and quirky as the good River we all know and love.
* Helena from ''Series/OrphanBlack'' is an AxCrazy fanatic with a murderous hatred of clones ([[YouAreWhatYouHate not knowing she's a clone herself]]). But she's beautiful, quirky, [[WoobieDestroyerOfWorlds sympathetic]], and [[http://www.youtube.com/watch?v=0WMIzmO-Ycw one hell of a dancer.]]
* Mel from ''Music/FlightOfTheConchords''. She does things like bake the band the cookies and has a not-so-secret crush on them that leads to some awkward moments between them. This description, although while accurate, would give you the impression that she was an {{Adorkable}} {{Dogged Nice G|uy}}irl. But she's not, she's actually an insane StalkerWithACrush. And those awkward moments are the result of her creepiness and the fact that she sometimes coyly hits on them in front of husband.
* On the SoapOpera ''The City'' (a retooling of {{Loving}}), the cast was being stalked by a SerialKiller. Much to the audience's shock, it was soon revealed to be petite, perky blonde Molly Malone.

* [[http://www.dailymotion.com/video/xh2efj_saturday-night-live-2006-natalie-portman-rap-hd_fun Natalie's Rap]] by ''Music/TheLonelyIsland'' informs us that Creator/NataliePortman is in fact a total psycho.

* The [[Myth/ClassicalMythology Maenads.]] Dionysus's followers who ''were'' once innocent, kind-hearted women until [[DrugsAreBad too much magic alcohol]] caused them to do horrific acts by tearing apart animals, children and sometimes men with their bare hands. They also killed poor [[TheWoobie Orpheus]].

[[folder:Professional Wrestling]]
* While Wrestling/{{Daffney| Unger}} was bordering on and sometimes crossing over into MsFanservice in her initial Wrestling/{{WCW}} run, this trope was the case in Wrestling/{{TNA}}. On TNA Xplosion, Don West described Wrestling/{{Daffney| Unger}} as "Just crazy enough to attract you and just crazy enough to make you want to get the hell away." When forced into a strip tease after Impact went to Monday nights she proceeded to give perhaps the most unsexy undressing a genuinely attractive person ever gave on Spike TV, as her eyes screamed "Die". She also got herself cutup more than all the other knockouts, perhaps barring Roxxi, usually when her own designs to maim people [[HoistByHisOwnPetard backfired.]]
* Was, or at least became the gimmick of Lin "Bitch" Bairon in SMASH. She had to be [[ChainedByFashion restrained by a chained dog collar]] before matches.
* Subverted at first in SHINE, as Kimberly started to let herself go in the earliest stages of her SanitySlippage, but then her losing streak was over and [[SheCleansUpNicely she cleaned up,]] during the latter stages.
* Nikki Cross from Wrestling/{{Sanity}}: She can be found smiling like a kid in a candy shop at the violence brought on by her stablemates, commandeering her stablemates for piggyback rides, and, during her sit-down interview, repeatedly batted away the mic and tried to do her interview by walking too close to the camera and holding the mic herself (badly).

[[folder:Tabletop Games]]
* ''TabletopGame/ForgottenRealms'' {{sourcebook}} ''Shining South'' got a sample NPC like this. A smiling half-drow (and both halves ''do'' work in her favour) cutie with GirlishPigtails. In a ''tasteful'' armor, with short sword and composite bow. According to her stats, a [[PsychoElectro Talos]]-worshipping NeutralEvil ranger / shadow marauder. As in, a Dambrath noble pillaging neighbour countries more [[BloodKnight for the fun of it]] than any economical benefits, and trained to not be stopped by boring things like fortifications for longer than an eyeblink.

[[folder:Video Games]]
* Eveline from ''VideoGame/ResidentEvil7Biohazard''. She portrays herself as a sweet little girl for the most part, but is an extremely sociopathic control freak who will incorporate anyone she sees into her "family", like she did to the Bakers, turning them into Ax-Crazy monsters.
* Venus from ''VideoGame/MetalGearAcid 2'' is an extremely beautiful FemmeFatale, and seems flirtatious, sexually confident, and yet somewhat vulnerable at first. She also kills a frightening amount of people in cold blood and seems completely incapable of actually feeling normal emotion despite her seductive, romantic play-acting. It's easily her sexuality which is her most screwed-up trait -- during the game, she gets aroused at least once by dowsing (in a DoesThisRemindYouOfAnything comedy scene), shuriken, murder, a corrupt genocide incident, a MadScientist experimenting on little children, her partner killing people, and her partner nearly getting blown up. Her partner, naturally, is creeped out horribly by her.
* ''VideoGame/{{Touhou}}'' has Flandre Scarlet, who, after spending almost five hundred years in the basement of the Scarlet Mansion to protect people from her [[PersonOfMassDestruction immense powers]], has [[ManChild the mind of a child]] and [[DoesNotKnowHisOwnStrength a poor understanding of restraint]], only wanting to play but with a tendency to "break" those she plays with. She isn't exactly murderous, but she's unstable enough that Marisa -- who has fought some of the most powerful denizens of Gensoukyou, which includes a few resident {{Physical God}}s -- actively avoids her whenever she goes to the Scarlet Mansion to [[StickyFingers steal books]].
* ''VideoGame/{{Darkstalkers}}'' has Bulleta/B.B. Hood. Adorable, {{Moe}}-laden TokenMiniMoe on the outside. AxCrazy PsychoForHire BountyHunter on the inside.
* Teemo in ''VideoGame/LeagueOfLegends'', a [[Franchise/FinalFantasy Moogle]] [[CaptainErsatz rip-off]] who couldn't care less about all the people he kills, but is slowly cracking from prolonged isolation from others of his kind.
** While how "cute" Jinx is varies from person to person (she's near-skeletally thin with pasty white skin and red eyes and is flatter than an ironing board, but a lot of people still find her extremely attractive, especially with her radically {{Stripperiffic}} outfit), she's also an AxCrazy BombThrowingAnarchist who loves blowing things up just because she can and is ''completely out of her gourd.''
** While slightly less "psycho" and more TroubledButCute (and TheWoobie) after lore retcons, Annie the Dark Child is still absolutely adorable in spite of being a budding pyromaniac whose only friend is her beloved teddy bear which transforms into a gigantic flaming monster when she wants to hurt somebody.
* Mimi from ''VideoGame/SuperPaperMario''. Just before her boss fight, [[spoiler:[[BodyHorror her head turns upside-down with an audible crack and explodes, and spider legs come out and carry her body around. The paper that is her head is crumpled up, possibly to signify the insane head trauma.]]]]
-->'''Mimi''': I'll shred you all like bits of confetti!
* Lovrina of ''VideoGame/PokemonXDGaleOfDarkness'' fits the bill perfectly. A cute, ditzy ValleyGirl with a penchant for 'beautiful' Pokémon... who is also the EvilGenius of a criminal syndicate responsible for the routine MindRape of Pokémon in order to transform them into soulless killing machines. She turns ''very'' nasty when pushed, and one of her subordinates describes her as "nothing short of terrifying".
* Alice from ''VideoGame/TalesOfSymphoniaDawnOfTheNewWorld'' applies to this: While she appears to be a cute, innocent girl, she's actually the leader of a terroristic army, being called a sadist by one of the [[ClingyJealousGirl main characters]].
* Twins Mireille and Mischka in ''VideoGame/ValkyrieProfileCovenantOfThePlume'', the former being female and the latter male. They kill purely for fun and hold a total lack of compassion for those they fight against, and ultimately kill -- even when it is not necessary, such as butchering a soldier who surrenders. Neither of them care to even hear the plight of rebel leader Natalie, who they kill. [[spoiler:She is implied to be their mother, unbeknownst to them.]] This disgusts even Wylfred, a character who sacrifices his own friends and childhood companions for the sake of revenge.
* [[MissionControl Blackbird]] from ''VideoGame/{{Strife}}''. She actually gets excited when you find new weapons and starts talking about their [[LudicrousGibs killing potential]]. Not to mention that this seems to be her preferred method of dealing with most problems that come up. To be fair, this is a FirstPersonShooter, so powerful weapons usually ''are'' a great way to deal with most problems that come up.
* In ''VideoGame/BlazeUnion'', we get Eimi, also known as Garlot/Gulcasa's sister Emilia. Nothing could be more adorable than her in the whole game... But if you go for the B route and field her too many times in battle, her love for her Brother Captain and her other friends, together with her desire to be useful to them, ends up turning into what drives her over the edge. As a result, Brongaa's blood manifests at full power in her, and she becomes a monstrosity that will remind many [[VideoGame/DeptHeaven Deptheavenites]] of Brongaa Possessed Gulcasa. At this point, she is bent on nothing but destroying anything that stands in her way, and Garlot is forced to put her to the blade, both to [[MercyKill put her out of Brongaa's torment]] and to assure his survival and that of everyone else.
* Ripper Roo from the ''Franchise/CrashBandicoot'' series, while at first completely insane, becomes like this after the epilogue of [[Videogame/CrashBandicoot1996 the first game]], where he is stated to have undergone intense therapy and higher education.
* [[spoiler:Iris Sepperin]] from ''VideoGame/{{Rosenkreuzstilette}}'' is generally a prim and proper little girl over the course of the first game's story. [[spoiler:Then, just before the final battle, she starts laughing madly and quickly shifts from her affable attitude to motormouthed insanity and arrogance during her VillainousBreakdown.]]
* Tiny Tina (subtitle "world's deadliest 13-year-old") from ''VideoGame/{{Borderlands 2}}'' decorates her house with bunnies and is fond of tea parties. In which she uses electricity to torture a bandit to death. Said bunnies are also filled with explosives, the use and making of which Tina is very proficient in. She also talks like a pimp and describes the aforementioned bunnies very... strangely. Yet, she's still extremely huggable.
** From the same game, there's also Gaige, the Mechromancer. For a school project, she developed DT (later renamed Deathtrap), a robot bullying deterrent -- with razor claws and lasers, who proceeds to kill her [[RichBitch rival]] when she threatens her. Her skills, apart from improving Deathtrap, allow Gaige to build up Anarchy, which improves her damage, weakens her Accuracy and makes her sound slightly unhinged.
* Harley Quinn has always been this, but in ''VideoGame/BatmanArkhamCity'' it goes to new heights. Her goons think she is worse than ComicBook/TheJoker.
* For all that Selphie of ''VideoGame/FinalFantasyVIII'' is a sweet little GenkiGirl, she's also far and away the most violently [[CombatPragmatist pragmatic]] of the player characters. Whenever she's involved in the planning phase of a mission, she always seems to suggest [[StuffBlowingUp using explosives]]. When planning how to escape [[TheAlcatraz D-District]], while a [[RidiculouslyCuteCritter Moomba]] is in the cell with everyone, she casually suggests skinning it and wearing it as a disguise. It's hard to tell if she was actually joking or not.
* ''VideoGame/FireEmblemAwakening'':
** Noire comes off as a delicate and soft-spoken young lady who has a timid demeanor due to [[spoiler:[[AbusiveParents being used as a guinea pig for her mentally-unstable mother's curses]] ''and'' coming from am incredibly doomed BadFuture]]. However, also BECAUSE of that, she has formed a split personality that surfaces whenever she gets fed up with the antics of her comrades or during the heat of battle. This side of her is also a bit of a [[LargeHam ham]].
-->'''Noire''': BLOOD AND THUNDER!!!!
** Henry is unfailingly cheerful, but almost every single line coming out of his mouth reveals his very screwed-up psyche [[spoiler:that comes from a ''horrifying'' DarkAndTroubledPast.]]
* Jenny Jaros of the ''VideoGame/SaintsRowTheThird'' expansion ''Gangsters In Space.'' Hoo boy. She's taller than [[StatuesqueStunner Female!Boss,]] plays a [[GreenSkinnedSpaceBabe Purple Skinned Space Babe,]] incredibly fit, and clearly works out judging by her figure. She starts out as a true {{Nice G|uy}}irl in awe of working with the leader of the Saints in a film, and the director [[KickTheDog punts her]] like some JerkAss TakeThat combination of Creator/HideakiAnno, Creator/ChristianBale and Creator/JossWhedon. Boss; who can easily qualify for this trope themselves, [[PetTheDog pets, strokes, nurses, caresses]] and generally takes her under her\his wing in the face of all this abuse, and when the director goes one step too far and tries to replace Jenny she reacts by gunning down the extras with prop firearms, then beating them to death if Boss stays around. When the Director reveals he is actively trying to kill them in the movie Jenny snaps, and in a scene that frightens even the AntiHero BadassInCharge DevilInPlainSight Boss runs down the director in a spaceship, killing him. Apparently Jenny has anger management issues but hot damn was it not deserving.
** Professor Genki as well, being a big, cuddly-looking pink cat with comical NerdGlasses who yells in enthusiastic broken English... and ''loves'' him some Murder Time.
* ''VideoGame/PhantasyStarOnline2'' has Lisa, who's a [[RobotGirl Cast]] and an instructor for rangers. She's always smiling and full of enthusiasm, but her conversations typically revolve around her love of filling things with lead and/or blowing them up. Her fanbase constantly makes the mistake of calling her yandere in spite of the fact that her personality is considerably childlike and she thus has no real interest in intimate relationships.
* There are many cutesy and lovable demons in ''Franchise/ShinMegamiTensei'', like MascotMook Jack Frost, Pixies (most Fairies), or even recurring demon Alice. None of them will hesitate to rip you to pieces if you aren't quick to deal with them with either firepower or some ''damn'' convincing gab.
* ''VideoGame/MogekoCastle'' has the Mogekos, little yellow cat-like creatures with curly tails who love prosciutto... and also high school girls. In very disturbing fashion. They love ''playing'' with high school girls, and don't particularly care about consent.
** Mogeko leader Moge-ko is a textbook example.
* Also from Mogeko games, Rawberry from ''VideoGame/TheGrayGarden'', a cute little pink-haired demon who will murder and devour anything in her way when she's not sleeping. [[spoiler:Including her teammates]].
* The titular CuteGhostGirl of ''VideoGame/SpookysHouseOfJumpScares'' is heavily implied to be not as innocent as she looks. Aside from the fact that her house is full of monsters and experiments, an in-game note has her [[BadBoss laughing at her head scientist's concerns before leaving him to be killed]]. The three mini-games feature her brutally murdering people. She also sounds increasingly more disappointed that you survived as you go further through the game. In addition, there's [[http://vignette2.wikia.nocookie.net/spookys-house-of-jump-scares/images/f/f8/Spooky-s-house-of-jump-scares-december-poster_by-stylishkira.png/revision/latest?cb=20150121141024 this image]] released for the December update, which implies she murdered SantaClaus. [[spoiler:It turns out that she is fully aware of how cute she is, and hates it. In fact, the entire reason she keeps a house of monstrosities is so that people can die in it and she can use their ghosts to form an army. Why? Because she won't be called "cute" anymore, of course.]]
* Ayla from ''VideoGame/{{Awesomenauts}}'' is cute Sadak child with psychokinetic abilities. She is also a psychotic prison escapist with a penchant for starting fires and destroying property.
--> '''Ayla:''' I'm a buttercup as sweet as can be. Please won't you buy some DESTRUCTION from me?
* Hina [[spoiler: as [[TrueFinalBoss Hibachi]]]] in ''[[VideoGame/DonPachi DoDonPachi SaiDaiOuJou]]''.
* ''Franchise/AceAttorney'':
** Dahlia Hawthorne, Phoenix Wright's girlfriend in ''VisualNovel/PhoenixWrightAceAttorneyTrialsAndTribulations'' seems [[YamatoNadeshiko nice, pleasant, frail and feminine]]... [[spoiler:but when Mia finally brings her to justice for her various crimes, she glares at her with GlowingEyesOfDoom while swearing revenge. Said revenge involves coming BackFromTheDead to murder Mia's sister Maya, who had done nothing to Dahlia, simply because [[SinsOfOurFathers Mia was already dead and beyond direct punishment]].]]
** There are a few male examples: [[spoiler:Matt Engarde]] in ''Justice for All'', [[spoiler:Kristoph Gavin]] in ''VisualNovel/{{Apollo Justice|AceAttorney}}'' and [[spoiler:Souta Sarushiro[=/=]Simon Keyes]] in ''VisualNovel/{{Ace Attorney Investigations|MilesEdgeworth}} 2''.
* The VillainProtagonist of ''VideoGame/YandereSimulator'' looks like an OrdinaryHighSchoolStudent, and can interact like her classmates like a completely normal teenage girl. However, she's actually an EmotionlessGirl who [[StalkerWithACrush stalks]] the first person who made her feel anything, and will murder anyone who gets in the way. Depending on how you play, she can be a ManipulativeBitch, [[PragmaticVillainy a pragmatic villain]], or an outright SerialKiller.
* ''Franchise/TheElderScrolls''
** Throughout the series, this is a trait of Vaermina, the [[OurGodsAreDifferent Daedric Prince]] of [[YourWorstNightmare Nightmares]], especially her voice. In ''[[VideoGame/TheElderScrollsVSkyrim Skyrim]]'', when she speaks to the player at one point, it's with the [[CuteIsEvil sweetest, most adorable voice you could ever hear]]... while she orders you to murder Erandur, a priest of [[LoveGoddess Mara]] trying to rescue a village. Taken UpToEleven in ''[[VideoGame/TheElderScrollsOnline Online]]'', where she has even more dialogue. Her voice is still adorable, and almost childlike... while gleefully describing how she is going to spend the next century or so [[MindRape Mind Raping]] you for killing her Champion, [[UnholyMatrimony whom she was apparently in love with]].
** From the backstory, [[TheCaligula Emperor Pelagius the Mad]] was said to be a handsome and personable young man...at least until [[AmbiguousDisorder the madness]] set in. Afterward, he was prone to bouts of AxeCrazy insanity. Once his madness became too publicly apparent, he was institutionalized and died only a few years later.

[[folder:Visual Novels]]
* ''VisualNovel/{{Tsukihime}}'' features [[spoiler:Kohaku, who appears to be a constantly smiling maid, but who [[TheChessmaster actually is responsible for most of the tragic events of the novel.]]]] One of the first tip-offs that something is off is that whereas [[spoiler:her EmotionlessGirl sister Hisui occasionally shows emotions such as surprise, embarrassment, or anger, Kohaku never loses that [[StepfordSmiler smile...]]]]
* This is practically the ''selling point'' of ''Franchise/WhenTheyCry'':
** ''VisualNovel/HigurashiWhenTheyCry'' features some of the more well-known ones, such as Rena Ryugu up there in the page image. A lot of the times the characters are delusional, so that either makes them Cute and Psycho or makes them [[UnreliableNarrator appear]] Cute and Psycho. [[spoiler:It's implied that all the central characters except Mion, Rena included, contracted Hinamizawa syndrome during many other iterations of the GroundhogDayLoop each; Rena would be a straight example in every one where she did. We're just only shown one. Well, there is another example of her going Cute and Psycho in the [=PS2=] arcs.]]
** ''VisualNovel/UminekoWhenTheyCry'': The [[WitchSpecies witches.]]
*** [[CreepyChild Maria Ushiromiya]]. In some scenes, the [[http://www.youtube.com/watch?v=A23uoWinmVc cutest little girl imaginable]]. At others, [[http://www.youtube.com/watch?v=XS-8iJ2Yn1s&NR=1 well...]]
*** Her mother Rosa can swap between [[TeamMom loving and motherly]] and [[AbusiveParents abusive monster]] at the drop of a hat. This being the result of her being severely bipolar combined with possibly having PTSD as the result of a harsh childhood and certain incidents shown in the 3rd novel.
* [[spoiler:Kozue]] in ''VisualNovel/ChaosHead''. [[spoiler:For a CuteMute ]], she sure seems awfully indifferent to the idea of killing people. Well, killing jerks. Hell, she got her sword in the first place so she ''could'' kill.
* Played for laughs with Riko in ''VisualNovel/AProfile''. As Masayuki's stepmother, she's very easily influenced, strong willed and tends to have thought processes at right angles to any normal person. Thus, she is prone to brainwashing her children and any number of other odd things.
* [[spoiler:Shiraki Aeka]] from ''Yume Miru Kusuri'' is a [[DrivenToMadness horribly]], [[TraumaCongaLine horribly]] justified example.
* [[TokenMiniMoe Ilya]] in ''VisualNovel/FateStayNight'', which is rather baffling to Shirou. Eventually he decides it's because she has no sense of right and wrong, and instead acts on any desire she has, no matter what it is.
* [[spoiler:Kazuaki Nanaki]] (aka [[spoiler:Hitori Uzune]]) ''VisualNovel/HatofulBoyfriend''. He's a [[spoiler:sleepy, gentle teacher]] who just happens to be so traumatized by [[spoiler:the death of his brother Nageki that he's constantly haunted by a shadowy manifestation of his guilt that he believes to be Nageki's ghost hating and blaming him for his own death]] that drives him to do some truly creepy things near the end of the Bad Boys Love route, descending into a MadnessMantra as he does so. Another character tries to help him and is almost strangled, and correctly concludes the following.
-->"He looks [[spoiler:pretty gentle]] on the outside, but I think he's pretty messed up inside."
* [[spoiler:Akane]] in ''VisualNovel/{{Suika}}''. And also quite the ShockingSwerve.
* [[spoiler:Junko Enoshima]] from ''VisualNovel/DanganRonpa''.
** From the sequel, ''VisualNovel/SuperDanganRonpa2'' [[spoiler: Mikan Tsumiki is an interesting case, as she's cute before catching the despair disease, but after she's revealed as a killer, she loses the cute factor quickly. However, if you play through her free time events, she still has that sadistic side, she just hides it better.]]
** From the spinoff, ''VideoGame/AbsoluteDespairGirls'', [[spoiler: Monaca]].
** For a male example, [[spoiler: Kokichi Ouma]] from ''VisualNovel/NewDanganRonpaV3''. Subverted when it was revealed that [[spoiler:he was GoodAllAlong and hated the killing game.]]
* Sho, the VillainProtagonist from ''VisualNovel/CrimsonRafflesia'' frequently changes her personality from cute and adorable to a creepy psychic murderer, breaking into fits of giggles while brutally dismembering people.

[[folder:Web Comics]]
* Irina from ''Webcomic/RasputinCatamite'' looks like a cute porcelain doll with pigtails, and speaks in third person, but seems to enjoy hacking people to death with an ax.
* Sophie from ''Webcomic/TheOverture'' is the most vile example of this. She uses her child-like appearance and sweet singing voice in order to lure children into her grasp. She then proceeds to torture them in order to [[LovesTheSoundOfScreaming hear their screams]].
* Tilly from ''Webcomic/WasteOfTime'' can be very cute and charming, but she will threaten to hurt you without hesitation.
* Buwaro from ''Webcomic/SlightlyDamned'' is a demon, but he loves everything and everyone. He'll invite you to play catch, or explore, or just give you a great big hug. But [[spoiler: if you value your life, do not remove his star pendant! While he goes berserk without it, it is not a BerserkButton, but a medical condition which the pendant is magically treating.]]
* ''Webcomic/ErrantStory'': Concussion is a cute little fairy nurse eager to help you. Her name is not an oxymoron, it is an ''euphemism''.
* [[http://www.sinfest.net/view.php?date=2010-10-15 Fuchsia]] from ''Webcomic/{{Sinfest}}'', though she had [[http://www.sinfest.net/view.php?date=2009-07-12 a short period]] of {{Yandere}}.
* Hinted at with The Little Girl and "[[CompanionCube Mr. Duck]]" from ''Webcomic/JohnnyOptimism''.
* ''Webcomic/{{Zoophobia}}'' has Cameron, a go-getting, curious young woman, who happens to be psychotically neurotic when in uncomfortable situations, or when around animals.
* In ''Webcomic/TheInexplicableAdventuresOfBob,'' adorable CuteMonsterGirl Molly has an identical twin sister (well, clone) named Golly, who varies between DeadpanSnarker and stark raving megalomaniac.
* {{Subverted|Trope}} in [[http://omaketheater.com/comic/63/ this]] ''Webcomic/Friday4Koma''.
* Violet from ''TheNoordegraafFiles'' is either this or a {{Yandere}}. She's implied to be very good looking, but hurt her (or her boyfriend), and you'll get a sword in your throat quicker than you can apologize. Not that an apology would help, of course.

[[folder:Web Original]]
* Three examples come to mind on ''Website/ThatGuyWithTheGlasses''; WebVideo/{{Ask That Guy|WithTheGlasses}}, with his poshness and suaveness hiding a monster, Bennett The Sage, who looks sweet and cute but can terrify Ask That Guy, and WebVideo/TheNostalgiaChick, who really is girly and generally decent, but has a mess of issues and sociopathic qualities underneath.
** As Creator/DougWalker does more and more sketch-review videos as himself, he'll usually portray his personality (which is '''in reality''' very kind and determinedly optimistic) as big smiles and InnocentBlueEyes covering a DepravedBisexual NightmareFetishist who like manipulating people.
* Pink and Blue from ''WebAnimation/CharlieTheUnicorn''. Cute little innocent sickeningly optimistic and 'imaginative' unicorns, who pull elaborate traps for OrganTheft.
* WebVideo/TheGamingPixie, apparently, particularly when she [[http://www.gamingpixie.com/99/all-videos/gamereviews/game-review-eversion-halloween-special/ reviewed Eversion]]. The review starts off [[TastesLikeDiabetes cheerfully]] enough... and slowly descends into fearsome. [[spoiler:Much like ''VideoGame/{{Eversion}}'' itself.]]
* The Laughing Clown from ARG/DarkDreamChronicle types in pink and generally acts like a little kid. She's also dangerously psychotic, once biting someone's tongue out for "[[ForTheEvulz shiggles]]". Even the [[AxCrazy other]] [[KnifeNut members]] of the [[TheMadHatter cast]] think she's completely insane.
* ''Roleplay/SurvivalOfTheFittest'' has a fair amount of these sort of characters, mostly of the BewareTheNiceOnes variety. A textbook example of this trope, however, would be Mariavel Varella of v2. Due to [[AbusiveParents abuse at the hands of her father]], she can go from a cheerful teenage girl to a hardened {{Delinquent}} who apparently once beat a man to death with a [[BatterUp baseball bat]] ''before'' being abducted. And when she gets to the island... [[AxCrazy well]], she just gets even more crazy.
* Jade Sinclair (codename Generator) of the Literature/WhateleyUniverse. She's cute and sweet and cheerful. She looks like she's ten or eleven. She 'invents' wacky devises. She looks like the harmless member of Team Kimba. Right up until she handles an attacker ''by stapling him to a tree with railroad spikes through his arms and body, and burns a message into his flesh''. That was in September 2006; By the end of the year, she has a body count over one hundred, mostly racked up during two separate trips over AnAsskickingChristmas vacation. To be fair, she didn't start any of that -- but she definitely finished it.
* Flippy of ''WebAnimation/HappyTreeFriends'', as he's [[BewareTheNiceOnes calm and sweet]] part of the time, but the minute [[BerserkButton something triggers]] him (by reminding him of [[WoobieDestroyerOfWorlds his time]] [[ShellShockedVeteran in the]] [[FunWithAcronyms Weaponized Animal Regiment]]), whether it be something like a car backfiring, the sight of a knife, fire, or an airplane, [[MeaningfulName he flips out]] [[JekyllAndHyde and switches to his]] [[SplitPersonality other personality,]] [[EnemyWithin Fliqpy,]] [[AxCrazy and starts killing everything around him]] [[ImprovisedWeapon rather creatively]] [[CruelAndUnusualDeath and brutally]] with a huge SlasherSmile on his face.
* Based from a murder case that occurred in Japan in 2004, [[http://knowyourmeme.com/memes/nevada-tan "Nevada-tan"]] became the memetic MoeAnthropomorphism of the concept.
* ''WebAnimation/{{RWBY}}'' has a heroic example in Nora Valkyrie. While she is a {{Cloudcuckoolander}} GenkiGirl, she also has shown BloodKnight tendencies on multiple occasions. For the most part she is a BadassAdorable, but...
-->'''Nora''': *about a JerkJock* Oooh! We'll break his LEGS! [[http://www.youtube.com/watch?v=vSvkRmWizw0 *excited smile*]]
** Villainous example with Neo. Cute, pint-sized, and [[http://i.imgur.com/gy9uMzr.png certainly psycho]].
* ''Podcast/KakosIndustries'' has Hailey Solomanari. She's adorable and girly to a fault with a sweet voice drenched in ValleyGirl speak but is also easily the most violent and intimidating character even when the cast is composed of nothing but villains. She's murdered people simply by having sex with them and relishes in absorbsing power from all the weak humans she's "fed" off of. When given a place of power for a few weeks, she just murders and feeds off more people all while narrating her achievements with the same cutesy dissonance.
* Jane Dean of ''WebVideo/TheVeronicaExclusive'' is a murderous psychopath, but it's easy to forget when she's charismatic, charming, and looks like [[http://67.media.tumblr.com/632e005073dd47ba1612522cda5648e5/tumblr_oei13drkL61r2lso9o3_500.gif this]]. Megan Lambie's prettiness is part of what makes the "psycho" part so unsettling.
* The Overly Attached Girlfriend, both in the videos created by Creator/{{Laina}} and the memes that sprang from those videos. While the OAG is undoubtedly physically cute, (naturally leading to a MisaimedFandom that says "She can be overly attached to me any time") her tendency for [[TechnicallyASmile large, disconcerting smiles]] complete with overly wide, unblinking CreepyBlueEyes makes her slightly off putting right from the start. Then you add in her {{Yandere}}-esque behaviors, which includes [[StalkerWithACrush stalking]], becoming [[ClingyJealousGirl violently clingy]] and [[IfICantHaveYou potentially murderous]] towards any man she takes a fancy to, and she starts becoming pretty scary. Notably while the memes about her tend to downplay the psycho side somewhat, Laina's videos make no bones about the fact that the OAG is ''terrifying'' and is only a few steps away (at most) from treating her "boyfriends" similarly to how Annie Wilkes treated Paul in ''Literature/{{Misery}}''.

[[folder:Western Animation]]
* Terra from ''WesternAnimation/TeenTitans'' is somewhat like this. She seems friendly, funny, and kind, although her DarkAndTroubledPast has saddled her with destructive tendencies that can, and if helped along by [[ManipulativeBastard Slade]], ''will,'' manifest as homicidal psycopathy. Her switch from a cool gal-pal to [[spoiler: Slade's ApocalypseMaiden]] was astoundingly dark, given the show's track record at the time.
* Jodi from ''WesternAnimation/TitanMaximum'' is showing signs of being this.
* ''WesternAnimation/AdventureTime'':
** Princess Bubblegum is not only a LadyOfWar, she's a ScienceHero who's capable of resurrecting the dead-- and she's [[PrincessesPreferPink completely adorable]] to boot. However, she does not have a BerserkButton--she has a berserk ''[[UpToEleven keyboard]]'', and she will go LaughingMad AxCrazy on you if you happen to hit a button. Usually though? [[SpoiledSweet She's genuinely very nice]].
** Flame Princess has a HairTriggerTemper and she's [[PersonOfMassDestruction destructively powerful]], capable of setting kingdoms (and at one point the entire planet) ablaze ''and'' she's evil; she could get mad at any time. But when she's ''not'' mad, she's ''really'' cute.
* ''WesternAnimation/MyLittlePonyFriendshipIsMagic'':
** Fluttershy, the {{shrinking|Violet}}yest, [[TheCutie sweetest]], [[RidiculouslyCuteCritter one of the most precious]] of the ponies in Equestria... and also the ''[[BewareTheNiceOnes scariest]]'' pony in all Equestria. [[BerserkButton Threatening her friends]] will put you on the receiving end of her [[DeathGlare Stare]], which made an adult dragon burst into tears. Some well-intentioned assertiveness training resulted in a complete 180 flip from an ExtremeDoormat to a violent, hateful bully. And after a bunch of animals refused her offer of friendship, [[http://www.youtube.com/watch?v=rwp60eYuie0 well...]]
-->"''You're... going... to '''LOVE ME'''!!!!!''"
** Pinkie Pie's GenkiGirl nature survives most things, and if it doesn't most of the time it means she only becomes depressed. But you should still [[http://www.youtube.com/watch?v=7nVjxIKgaGc never break a]] [[PinkySwear Pinkie Promise.]]
** Twilight Sparkle is CuteBookworm extraordinaire and the [[OnlySaneMan Only Sane Mare]] in Ponyville most of the time, but multiple episodes showed that [[BewareTheNiceOnes she can be more unstable and dangerous than the rest of]] [[FanNickname the mane six]] ''combined'', with [[http://www.youtube.com/watch?v=3Tinq3ip85g one scene]] from [[Recap/MyLittlePonyFriendshipIsMagicS2E3LessonZero "Lesson Zero"]] taking the trope to an art form.
-->"[[NightmareFace HIII, GIRRRRRLS]]!"
** Princess Luna is this in {{Physical God}}dess form. She is the very definition of {{Adorkable}} and has the [[http://www.youtube.com/watch?v=XozImlvJBBE absolute]] [[http://www.youtube.com/watch?v=RbViHWSazDk cutest]] facial expressions in a show that seems to run on cute facial expressions. Yet the first time we meet her she is an OmnicidalManiac who is trying to bring forth TheNightThatNeverEnds and is consumed by envy of her sister's greater popularity. Even after she is cleansed of all evil she retains a HairTriggerTemper which expresses itself through her fondness for [[ShockAndAwe summoning lightning in the sky]] to add emphasis to her sentences.
* ''WesternAnimation/CodenameKidsNextDoor'':
** [[AsianAirhead Numbuh]] [[GenkiGirl Three]], [[BewareTheNiceOnes when you get her angry enough]]. [[spoiler:Her little sister Mushi]] is ''even worse''.
** Lizzie in her first few appearances, before [[CharacterizationMarchesOn she mellowed out]] and became a ClingyJealousGirl.
** Sonia looks like a sweet little girl who doesn't belong in a world of kids fighting adults, [[spoiler:but then you tell her you're going to shove her into a dark place. Prepare to get your ass kicked.]]
* ''WesternAnimation/{{Metalocalypse}}'' has Toki Wartooth, Dethklok's [[ManChild adorably immature]] rhythm guitarist, has what could be called an ''unconventional'' mental state. Sometimes, this manifests as pastel-colored acid-trip musical numbers. Unfortunately, he also has substantial anger management issues, particularly when the show's been putting him through a round of BreakTheCutie.
* The title character of ''WesternAnimation/{{Kaeloo}}''. While her Jekyll-and-Hyde-esque split personalities [[HulkingOut physically]] differ (cute, innocent frog and violent tower of toad muscle respectively), they overlap so heavily in the later episodes that some scenes give off the impression that at times HydePlaysJekyll.
* ''WesternAnimation/FamilyGuy'': Joan is shown to be very sweet and she falls in love with Quagmire. The two were married, but when Quagmire mentioned the prospect of divorce, Joan does a complete 180 in her mannerisms and threatens to kill herself and Quagmire.
* Izzy from ''WesternAnimation/TotalDrama''. In ''Revenge of the Island'', Zoey is this ''and'' BewareTheNiceOnes personified after she's pushed too far.
* Bubbles in both 1998 and 2016 incarnations of ''WesternAnimation/ThePowerpuffGirls,'' but it's more frequent in the 2016 series, whereas in the 1998 series, she reveals herself to be this in "Bubblevicious", where she kills a bunch of monsters ''with ease'' and also beats up citizens for minor infractions.
* Mabel of ''WesternAnimation/GravityFalls'' occasionally slips into this. "We have an ax! Ree! Ree! Ree!"

%% Once again, no real life examples.