The Fake Cutie is either a full-grown woman or otherwise mature person, but insists on dressing, speaking and acting like a child, sometimes to a sickening degree, or at least much younger than she is in order to be cute and "get dates" or other benefits.
This cutie act is actually camouflage to hide her intelligence, her true self, her nefarious intentions, or her insane jealousy. Sometimes she knows full well how shaken up her behavior makes her foes, and takes great joy in seeing them squirm. She tends to be very manipulative and is often murderously dangerous to those that see Beneath the Mask. For children, may involve levels of Troubling Unchildlike Behavior. However, it is entirely possible that she may have less malicious intentions.
She is the cute counterpart of the Stepford Smiler, and may even be her daughter. The Bitch in Sheep's Clothing is her meaner sister. The fully grown Fake Cutie is invariably a Psychopathic (Wo)man Child, unless she is of the Broken Bird variant.
While this trope is almost Always Female, examples using little boys are not unheard of.
- Mimi Yoshioka from Lovely Complex acts this way around her crush, Otani. She does eventually slip, revealing her true nature.
- Washu in Tenchi Muyo!, though it's definitely an act; she can move in and out of it at a moment's notice (she even physically alters her body to switch between the usual "Cutie" act and her true age). She's the smartest person in the galaxy, and Really Twenty Thousand Years Old... And that's in the continuities where she's closest to what she appears.
- On top of being a Genki Girl, Vandread's Dita fits this description pretty well. She talks like a child ("Hello, Mr. Pilot!") and acts like one, even if you ignore the fact that she plays with toys. Her Character Development reveals a more complex reason why she grew up this way: When she was little, being a Cheerful Child brought hope and smiles to the adults around her in a tough time. She resolved to be as cheerful and cute as possible to continue helping out as best she could, and it kind of stuck. To her credit, she didn't let this get so out-of-proportion that she didn't learn more practical skills, like cooking, sewing, flying a Humongous Mecha and delivering babies - The last skill in particular was instrumental to saving the entire crew in the opener of the second season, as the cry of a newborn baby was the password to unlocking the central computer of the ship from its BSOD.
- Miu from Strawberry Marshmallow. Cute is practically a way of life for her, but so is being a Jerkass.
- Yokohama Kaidashi Kikou seems to suggest that, if we ever develop Ridiculously Human Robot Girls we'll probably intentionally program this trope into them...and they're probably right.
- Death Note's Near is an eighteen year-old genius who sits around playing with toys all the time and who, when he has to fly to Japan, gets an ally to essentially chaperone him because he's never flown on his own before, then sits on the flight fiddling with a model car. He's not trying to be cute, though - he's just extremely weird.
- Misa is this whenever she has all her memories intact and serves as the second Kira. Otherwise, she's a genuine cutie.
- Komoe Tsukuyomi from A Certain Magical Index wears bunny pajamas and ends her sentences with 'desu'.
- Akira in Lucky Star, despite being 14 and thus younger than anyone else in the cast, has the personality of a dried up old entertainer completely disillusioned with the industry. So the joke behind her little Lucky Channel segments is the rapid personality switches between a kawaiiko girl even younger than her real age and her bitter, real personality. The cutesy act apparently doesn't go over well with the audience compared to Minoru or the main cast, of course.
- Yaya from Shugo Chara! goes as far as having her Shugo Chara, AKA Anthropomorphic Personification of her True Self, be a baby. Her Magical Girl form even wears bunny pajamas and her special attacks include rubber ducks and a giant rattle. Oh and she's prone to burst into tears if hurt.
- Biscuit Krueger in Hunter × Hunter is an expert combatant and, for some time, a mentor to the main characters. She has the ability to alter her body to appear like a preteen girl; she does so because her true form is gonk and she is ashamed of looking like that. She also likes the bonus of keeping a low profile and, if she ever needs to get in a fight, having the opponent go easy on her due to her cuteness.
- Flay Allster from Mobile Suit Gundam SEED becomes this when she goes yandere after her dad's death, acting sweet and kind to Kira while planning to get him killed in battle as "punishment" for him not being able to save her old man. Character Development fixes that, however. And then she dies.
- Muteki Kanban Musume: Megumi is a full-grown woman that insists on dressing, speaking and acting like a cute child, sometimes to a sickening degree, as a ploy to get clients into her bakery.
- In Bakemonogatari, we have Nadeko Sengoku, as revealed in Nadeko Medusa. She acts cute, plays victim and behaves non-confrontationally in order to avoid responsibility and get people on her side. In truth, she hates hard work and emotional stress, is extremely irresponsible and selfish, deeply jealous of Hitagi's and Shinobu's relationship with Koyomi (who she's yandere for), and believes nothing is ever her fault.
- Nui Harime, a bubbly, bouncy, adorable girl dressed all in pink, and also the murderer of Ryuko's father in Kill la Kill.
- Nico Yazawa from Love Live!. On stage, she's a cute and cheerful idol who likes to go "Nico Nico nii~!". Outside of it, however, she's an Attention Whore with the temperament of a grumpy old lady.
- Road Kamelot from D.Gray-Man qualifies. Even though she appears to be a child, she's actually the oldest Noah and a total sadist, once stabbing Allen in the eye and then licking off his blood.
- Roma Hoito from Tokyo Ghoul. When initially introduced, she's a clumsy and forgetful waitress that has a crush on Kaneki because of his fame in the Ghoul community. She's a source of comic relief, and a slight annoyance to her coworkers because of her frequent mistakes. This cute personality is entirely false — she's actually a member of the Clowns and a sadistic Loony Fan that considers Kaneki's suffering romantic. Even fellow Clown Nico is mildly disturbed by her obsession with destroying Kaneki's happiness.
- Youjo Senki: The eleven-year old brutally ruthless military commander Tanya Degurechaff usually tries to present herself as an adult in a child's body, but will occasionally take advantage of being a cute young girl when it suits her. In one case, when required by International Wartime Law to announce beforehand her attack on an enemy munitions factory, she does so in an overly-cutesy girlish voice. This leads the factory workers to assume that she is just some girl who is using the radio to play a prank, so nobody evacuates or prepares for an assault. Two minutes later the factory explodes.
- Princess, Ange, Dorothy and Chise from Princess Principal will act cute as part of their cover as spies operating out of a prestigious school, but they will switch to ruthless at the drop of a hat — they are spies after all.
- In Blend-S, Mafuyu is the group's Token Mini-Moe, Deadpan Snarker, and, more often than not, the group's Only Sane Man. She's also a 20-year-old college student despite her short height and youthful looks. However, she acts completely different in her job as a waitress at the Cosplay Café Stile, where the staff act out character types and Mafuyu is cast as the "Little Sister Heroine". She plays up her cuteness for maximum effect, speaking super sweetly to the "Onii-chans"/"Big Brothers" who patronize the café and, on one occasion, using her act to steer customers away from ordering items they couldn't make due to lack of ingredients.
- Momo Belia Deviluke from To Love-Ru presents an innocent, smiling face to the public. Behind that mask hides a girl that can be, at turns, a Manipulative Bastard, an Ax-Crazy Little Miss Badass and a Lovable Sex Maniac that wants to create a harem around the boy she loves, Rito.
- Rainbow Rowell's Runaways gives us Abigail, Molly's new best friend, who is ostensibly a pretty thirteen-year-old, but who is in fact a middle-aged woman who used magic to avoid physically aging past thirteen... and wants to do the same to Molly.
- In Siege of the Crystal Empire story arc of My Little Pony IDW comics, this trope is invoked by Umbrum, who initially appear to Radiant Hope as cute, pony-like pixies. However, it is all just a ruse to get on Hope's good side and manipulate her into believing that Umbrum are actually harmless, innocent creatures who were wrongfully banished by evil, xenophobic Crystal Ponies. When Princess Cadance accidentally reveals their true forms by using her magic in their presence... let's just say, it ain't pretty.
- Nermal from Garfield is actually shown to purposely stunt his own growth to stay a permanently cute kitten.
- Agent Diamond, from Akatsuki Kitten: Phoenix Corporation Overhaul, seems to swing between this and Cute and Psycho. She is generally sweet and happy a lot of the time... she just has an extremely frightening tendency to do things like kill people while giggling madly. There may be a Freudian Excuse behind that, as well as basic nature: she "used to be" Renesmee Carlie Cullen and has only grown less human in mind since then.
- Loki: Agent of Doomgard gave us Loki Goddess of Traps and Poisons, who is a short, cute, harmless looking woman... so scared and vulnerable. Well, yes. It IS a trap. When she got arrested the "cops" found a head in her freezer.
- Orphan: Esther fits this perfectly, her entire life is based around hiding her Ax-Crazy personality, and the fact that's she's in her thirties with a cute-girl facade.
- In What Ever Happened to Baby Jane?, Jane dresses like a little girl and sings songs that would be adorable for a little girl but are incredibly creepy when sung by an adult.
- All the Boys Love Mandy Lane, Mandy Lane seems like an innocent, virginal, late-teen girl who all the teenage boys are obsessed over at high school. Turns out she's an evil, manipulative, female who uses her charms to make a multiple murder and suicide pact with her nerdy male best friend, which she then breaks by killing him too. And she gets away maintaining her innocent persona.
- Gogo of Kill Bill. Sailor Fuku on the outside, lethal meteor-hammer-wielding psychopath on the inside.
- Almost all of the women in Women Who Flirt, but especially the main character's rival.
- Natasha Rostov tries this for a long time in War and Peace. She's eventually broken though.
- David Eddings' The Elenium and The Tamuli novels have the goddess Aphrael. Her "real" form is an adult woman, but she always appears to everyone as a six year old girl. This allows her to use The Power of Love on everyone. When a cute young girl asks to sit in your lap, no one can refuse. Once she sits in your lap and gives you a kiss, she will get her way on everything she wants.
- Willie Connolly in J.R. Lowell's 1972 thriller Daughter of Darkness starts out as a Deliberately Cute Child Prodigy, and becomes this as she matures. She doesn't want her father to realize she is in puberty, because she thinks (and is probably right) he will send her away to some stupid prep school instead of allowing her to stay home and care for him. She spends the next few years with a tight bandage around her breasts and dressing like an eight-year-old. It works for a while.
- Worm's Bonesaw is the veritable patron saint of this trope. She dresses in pigtails and dresses, is cute as a button, hates swearing, and is personally responsible for a not insignificant chunk of the Fate Worse than Death and the And I Must Scream pages.
- Princess Ariel of Wizards and Warriors was the epitome of this trope.
- Similarly, Vala Mal Doran of the later seasons of Stargate SG-1 is portrayed as being in her early to mid thirties, but most of the time acts like she's in her early twenties at best, even wearing her hair in a pair of unbraided pigtails. It's almost certainly calculated to make her appear harmless, because in an episode when she loses her memory, aside from trying to continue her thieving and lawless ways, she acts more maturely. It's helped when people make reference to pop culture, as she's not from Earth, allowing her to demonstrate something approximating real naivete.
- And when she stops acting cute and acts competent instead, she unnerves everyone. It's a skill.
- Amy Hughes on Dead of Summer. Initially presented as a wholesome, virginal Final Girl, she's actually the Big Bad who was responsible for every murder on the show, using a Satanic cult as her Unwitting Pawns to summon the demon Malphas. She murdered her best friend Margo in order to get her job at Camp Stillwater, and she embraced her Demonic Possession, seeing Malphas as the only one who "understood her".
- A subversion occurs during Murder Mystery Dinner Train, where one of the suspects, a one-time child actress, was revealed to have remained young and cute so long because her agent used a variety of drugs to stunt her growth and keep her in the movies as long as possible.
- Rosalie in Oh Dad, Poor Dad, Mama's Hung You in the Closet and I'm Feelin' So Sad is an oversexed version.
- One of the titular character's peers in The Madwoman Of Chaillot is a downright ancient version of this trope.
- B.B. Hood (pictured above) from Darkstalkers (notably, the only playable character in the franchise who is a perfectly ordinary human, for a given value of "perfectly ordinary human") plays up her cuteness, but is more vicious and psychotic than most of the monsters in the cast.
- Momo Karuizawa, the skipping, pigtailed, stripey-socked, 4 1/2-foot tall tennis player from Rival Schools. Oh, and she's also evil. But she gets better in the Gorin path - it turns out a good part of said evil came from her loyalty and love for Kurow, and then he throws her under the bus. Shouma saves her and tells her to pick a side, and this drives Momo to a HeelFace Turn.
- Vanille from Final Fantasy XIII is a Deconstruction of the Cutie. She pretends to be innocent in order to hide her guilt. While she's by no mean a bad person, some of the the main characters, particularly Lightning and Sazh, end up not trusting her.
- In Super Robot Wars Z2, Marilyn Catto's character encyclopedia entry mentions she's taken cosmetic surgery to maintain her looks and she makes the men in her squad treat her like a princess, which could mean that she is a case of Older Than They Look.
- Zigzagged with Dead or Alive 5 Ultimate character Marie Rose. If she loses she'll sit on the ground and sob but then mug for the camera as if it's an act. That said she often is The Cutie and cheerfully smacks the crap out of her opponents with a smile on her face.
- Flowey from Undertale is an adorable, talking flower who introduces himself as supposedly your best friend only to take advantage of the player's naivety, to try and convince them to walk straight into his attacks. It all goes nowhere but downhill from there. Later subverted, though, as it turns out that he actually Used to Be a Sweet Kid, and, given half a chance, reverts to old habits.
[player avoids the "white friendliness pellets"]
Flowey: Is this a joke? Are you braindead? RUN. INTO. THE. friendliness pellets.
[if player continues to avoid the "friendliness pellets"]
Flowey: [trembling text] You know what's going on here, don't you? You just wanted to see me suffer.
[Flowey creates a huge, unavoidable circle of bullets]
Flowey: DIE. [reveals his Game Face and lets out an Evil Laugh as the bullets close in]
- Alice from Tales of Symphonia: Dawn of the New World is this in spades. Not only is she older than she looks (she's 18, but could pass for being in her early teens), but she's a sadistic bitch that is more than willing to torment her underlings and claim them as her pets. She is also very manipulative, using her looks to trick people by lying blatantly.
- Dahlia Hawthorne of Ace Attorney is introduced as a sweet, innocent girl in a pink dress with butterflies fluttering around her, winning over everyone in the courtroom. This hides her true nature, which is a scheming, manipulative murderer.
- Xenoblade Chronicles 2: In a sidequest, it's revealed that the Nopon race owes their nature as Ridiculously Cute Critters to this: centuries in the past, a Nopon known as Captain Nopopon realized that the other races thought the Nopon were cute, so he deliberately fluffed up his fur and started talking in pidgin with a Verbal Tic so he could take advantage of his race's predisposition towards cuteness. The entire rest of the species followed suit, to the point that in the present day acting and looking cutesy as a means to manipulating the other races is simply accepted as a part of Nopon culture.
- Kohaku from Tsukihime. Her faked personality isn't revealed until you get to the second to last route of the game, though there are hints beforehand. However, it actually appears as though she's been faking her personality on accident and out of habit. As a child, she was something of an Emotionless Girl, but now when Shiki see her he thinks to himself, 'If only Hisui had some of Kohaku's cheer.' *wince*
- Liliana in Princess Waltz. Some of it is natural, some of it is obfuscating stupidity. Hints start dropping fairly early that she's not as young as she looks.
- Higurashi: When They Cry:
- Rena [[seems like this with her Obfuscating Stupidity and occasional forays into Cute and Psycho territory, but we eventually find her cute personality is not an act. She's just a nice teenage girl trying to put her Dark and Troubled Past behind her so she can live happily and peacefully surrounded by her dear friends. Unfortunately, she lives in a Town with a Dark Secret that makes this all but impossible.
- A straighter example would be Rika. She spends most of the time looking adorable and acting like a child, much to the joy of Rena (when she's not crazy). But come the second half of the series, we learn that she is in fact quite mature (and somewhat cold), having lived through hundreds of years worth of bloodbaths, at the end of which she is always killed. And her only option is to live through each one, waiting until a miracle occurs or until she cannot resurrect into another timeline.
- Hiyoko Saionji from Danganronpa 2: Goodbye Despair is not only the same age as the other students despite looking like a little girl, but she's also rather cruel and sadistic towards everyone else, particularly Tsumiki. It doesn't help that she has rather childish mannerisms, which makes her actions come across as even more unsettling.
- Played straight by Aizawa Eiichi of G-Senjou no Maou, who puts up a cute front to get close to the girls he wants, though Kyousuke knows his other side very well and Kanon easily saw through it.
- Bailey from Alternate. She even etches smiley faces on her food.
- Runie from 200:20 because of her carefree behavior and the fact that it's lead to believe that her behavior is mostly just an act she's putting on for one reason or another◊
- Lutark Lampri from Hackbent is a decent male example. He's positively adorable in fake Moe-mode, disconcerting when he shows his true nasty colors, rather terrifying when he goes into full Villain mode.
- LessThanThree Comics' Brat Pack features Pixel, who is one year younger than her team-mates, and acts about five years younger most of the time, and has a blast doing so.
- This is spoofed on Drawn Together with Strawberry Sweetcake, a parody of Strawberry Shortcake. She turns out to be a homicidal and kinda-cannibalistic Stepford Smiler.
- Mary "Baby Doll" Dahl of Batman: The Animated Series was a child actor with a growth deficiency which prevented her from physically aging, and similarly prevented her career from advancing as well. Years later, she snapped and started kidnapping old cast members, but kept doing so in character as "Daddy's widdle precious". It's only at the end of the episode, when she stumbles in front of a funhouse mirror that seems to show the adult form she could never have, that she breaks character and reveals what she's really like, in a speech that's a real Tear Jerker.
Baby Doll: Why wouldn't you let me make BELIEVE...?!
- Animaniacs: Dot Warner likes to think of herself as The Cutie and takes her cuteness very seriously, but she's hardly innocent. Press her buttons and risk pain, call her "Dottie," and you die.
- Gravity Falls has Li'l Gideon, a child psychic who everybody loves. Well...turns out he's a vicious Creepy Child who tries to kill Dipper after he tries to tell Gideon that Mabel's not interested in him, and is willing to summon a demon in order to get the deed to Mystery Shack.
- Wander over Yonder has Little Bits, who at first appears to be a poor stray who Wander finds unbelievably cute, claiming he'll do anything for her...but then it turns out she's actually mind-controlling him so she can bring him to Lord Hater.
- Jimmy Two-Shoes: Heloise, who has the appearance of a cute little girl but is a Mad Scientist and enjoys being mean.
- The Bugs Bunny cartoon Baby Buggy Bunny has Ant Hill Harry, aka Baby Face Finster— a dwarfish bank robber who disguises himself as a baby. He can look very adorable— and at one point beats seven shades out of Bugs with a baseball bat.
- From the main characters, this is entirely Tweety's shtick. His act is that of an innocent, sheltered bird who can be easily taken advantage of by cats and who then proceeds to arrange their downfall from as high as possible.
- Phineas and Ferb: Suzy Johnson may seem like a cute, innocent kid, but when she's alone with Candace her true personality comes out with a vengeance. Subverted in that she only does it when her brother and Candace's crush Jeremy is around, because she only does it to manipulate him. When it's just the two of them Suzy is (in her own words) "off the clock", and has even assisted Candace in trying to bust her brothers.
- The season 8 finale of My Little Pony: Friendship Is Magic reveals that Cozy Glow's ridiculously cute, sweet demeanor was all an act, and that she has been plotting to take over the Friendship School and steal all of the magic in Equestria. She's even pen pals with former Big Bad Lord Tirek, who admits to being impressed by the little filly's ambition.