"Genki" is Japanese for energetic or enthusiastic. The Genki Girl is a character — usually a schoolgirl, but not always — who acts like she's been mainlining Red Bull and crystal meth. She is possessed of an over-abundance of energy, such that she runs everywhere (often with arms waving wildly or outstretched like airplane wings), speaks quickly (sometimes unintelligibly so), and always does everything fast, fast, fast! She's filled with confidence and determination, regardless of whether she's competent or not. Although usually played exclusively for comedy, sometimes the Genki Girl slows down for a serious or introspective moment. But not for long — she lives her life full-throttle. To sum it up, a good way of telling whether a female character is genki or not is to see if her family and peers are exhausted, astonished or even creeped out by her chronic outbursts of vitality. (A female character is by far the more common version, but this trope is not limited to females)
Despite what you'd think, the Genki Girl is usually not The Ditz. However, there have been a few blends. She is, of course, very often a Motor Mouth or a Nicknamer. If she focuses her powers on getting a boring guy to relish life, she's a Manic Pixie Dream Girl. Less sympathetic portrayals often make her the Jerkass of the group. Alternatively she could be both. Some are even the resident Cloudcuckoolander.
If this is a RPG setting, she's almost always going to be the Fragile Speedster, thus fitting her personality.
If a work of fiction gives its characters symbolic flowers that represent their personalities, the Genki Girl will likely get the sunflower while her animal is the cat, though her energy won't necessarily make her go crazy.
Whatever you do, don't give them too much coffee, cola or sugar, and definitely teach them that hard drugs are very bad. This is why she may be preferred with somebody who is practical.
Voice actors sometimes become famous for just being able to keep up the role.
Compare Fist Pump and Hot-Blooded. Compare The Pollyanna for endless optimism and cheer rather than energy. Contrast Emotionless Girl.
Keet boys usually, but not always, fall into this trope as well.
Has a huge tendency to do the glomp
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Anime and Manga
The titular character of A Little Snow Fairy Sugar, much to Saga's initial annoyance. Saga's cousin Kanon would also qualify.
Self-described "wildcat high school girl" Tomo (pictured above). We know she's a Genki Girl because "Genki!" is the first thing she says.
Yukari-sensei is what happens when the Genki Girl grows up. Or doesn't.
Miria Harvent from Baccano!, who even comes with the equally hyperactive boyfriend and partner in crime, Isaac Dian. They seem to have an amplifying effect on each other (at least their seiyuu have this chemistry.) Since they're inseparable for their entire screen time, it's impossible to tell how Genki they are individually.
Nakuru Akizuki from Cardcaptor Sakura, who is also a Manipulative Bastard. And being a technically genderless spirit being rather than a human girl, though she more or less refers to herself as a girl.
Shirley and Euphie, the respective Love Interests of Lelouch and Suzaku, are also these, and give some much needed lightness to their troubled lives. Unfortunately, and ironically enough, things do not well end for either of them, and both of their heartbroken counterparts descend further into darkness.
Pino from Ergo Proxy, who is really more like a Genki Robot that looks like a girl.
Akiko from Eve No Jikan acts like this when the main characters first meet her. They automatically assumed she was human, only to discover that in public, she is an emotionlessRobot Girl. This is a facade, though, so being a Genki Girl really is her natural personality.
Winry Rockbell of Fullmetal Alchemist. She goes full-on Bishie Sparkle, Squee, and arm-wavy mode whenever she sees something cute or acting cute (Elysia Hughes weeded this mode out of her the first few minutes after she met her), something's caught her interest (mainly anything involving automail, i.e. Rush Valley, or a shopping spree in Central), or a rather vicious (and comic) argument with Ed (again, mainly over automail). The times that she's not Genki mode are when she's realized something tragic or an error in her construction (i.e.: learning about Maes' death or discovering the missing screw in Ed's newly constructed automail arm after he left to go investigate Laboratory #5), or when she's concentrating on building a new automail body part.
The title character is a very avalanche of Genki Girlness, who drags everyone nearby along with her. This is expressly stated in the audio drama's main song "First Goodbye", which is, in-canon, written by Haruhi herself (and just as autobiographical as "Lost my Music") with the line "Igai to genki!".
Tsuruya-san, a minor character, is somewhat of a Motor Mouth and a cheerful Genki Girl, with emphasis on the 'cheerful'. A natural co-conspirator with Haruhi. (When Haruhi isn't working with Little Sister.)
In the 9th/10th novel introduced Yasumi absolutely qualifies. No surprise, considering her true identity: Haruhi's subconsciousness.
Miyako in Hidamari Sketch. While she's prone to sleep in class and can sometimes sleep for 12 hours in one go, once she is awake, she's quite energetic. One episode shows her coming into Yuno's apartment, showing no signs of having awakened two minutes ago; another has Yuno pointing out that she's hyper even in the morning. "That was quick!" is a common phrase applied to her actions, whether she's gobbling down food or making art (usually impromptu). But despite all her teasing, she's a likable person, a good friend... and surprisingly, does well in school!
Torako from Hyakko. She's of the Genki-Ditz blend, considering she makes her debut by leaping out of a window. It's a second story window, but she definitely chooses the quickest way to get from point A to point B.
Hyouka gives us an interesting example in Chitanda Eru, who is so vivacious and bubbly that Oreki often perceives her as having an inner glow.
Ritsu from K-On!, essentially holding the club together with her enthusiasm.
Sora from Kaleido Star is amazingly energetic. Emphasis on amazingly. Her friends Rosetta Passel and Marion Begnini try to keep up with her, but they still have a way to go.
Mako Mankanshoku from Kill la Kill is one of the genkiest girls of recent anime, and is the perfect foil to resident angry Hot-BloodedBadass Ryuko Matoi. Whenever Mako opens her mouth, you can be sure that she will say something either crazy, hilarious or both sooner or later. Really, this girl is a walking Crowning Moment of Funny.
Chizu of Kimi ni Todoke is hyperactive to the point where she involuntarily knocks people down in the school corridors and gets irritated comments from other characters on a regular basis.
Kurata Sana from Kodomo no Omocha is the archetypical Genki Girl. The Fan VidCaffeine Ecomium gives some inkling of just how energetic she is; none of the sequences in this video have been sped up.
Haruna from Kokou Debut (also titled High School Debut) is so genki she's almost Badass Normal. One of her recurring sentences is "let's work hard!" — cue to high-fiving everyone, running around doing more physical work than the guys and tiring everyone out. Oh yeah, and she can put up a physical fight with guys including potential assaulters. Her over-the-top genki-ness is arguably part of what makes her such an endearing character.
Hikari from Lamune. Noted by the male lead (her cousin) that she acts much like a kid, despite being a year older than him.
To a lesser degree, Hikaru Shidou from Magic Knight Rayearth. She's incredibly friendly, energetic, and upbeat. It's even more so in the anime, where she has some No Indoor Voice moments.
Several characters in Mahou Sensei Negima! count; Makie is the most notable example. The entirety of Mahora Academy is described as such, even the boys, by the teachers themselves. It was stated that during a previous School Festival, they arranged an academy-wide game of tag, and afterwards decided not to do that again because there were too many injuries. That year, they were going for a (slightly) more sedate game of Hide-N-Seek, until the Big Bad of that arc provided an army of robots, and they decided to unleash the students on them instead.
The titular Cute Ghost Girl from My Lovely Ghost Kana is a strange example. In the back story, she gruesomely took her own life, stabbing herself in the chest many times, and her ghost remained behind, trapped in the apartment building where she died. By the time the real story begins many years later, Kana has forgotten most details of her life, including why she decided to end it. When Unlucky Everydude Daikichi (unable to afford to live anywhere better) moves into the allegedly haunted building, he has a hard time accepting that this cheerful, energetic girl (overjoyed at finally having some company) is actually a ghost.
Ahiru from Princess Tutu — who is a duck that can magically turn into a girl — spends most of the show running at top speed, squawking out words so fast it's hard to keep up. She's not even aware that her energy level is unusually high, judging by her confused reaction when another girl from her school fails to keep up with her. This may be because her friends Pique and Lilie are about as energetic as she is, or it may be because she's a duck and doesn't know any better.
Excel Saga's director also gave us Poemi from Puni Puni Poemi. Impossible as it may sound, at times she surpasses even Excel in genki-ness. And this time, Poemy's dub actress strained her voice on the first day of recording.
Usagi Tsukino of Sailor Moon is an obvious example. Eternally cheerful and loud. Her monologue from the first anime's Stars season perfectly expresses it. Here's just the end:
Oh, it's almost 7 o'clock on Saturday! Dinner time!
With mom's food, and the TV on, my cheerfulness goes up a hundred times! The peace of school, and the peace of my family, and the peace of my sweetheart, and the peace of the universe, I will protect them all together!
Time to eat!
Yes! Energy level at two hundred percent! Cheer bursting at ten billion horsepower! Transform!
Minako is even more energetic. She's usually (apparently) calm, but whenever something sets her off... Well, she once outran a car while weakened by having donated blood, having ran all the day and with her Pure Heart Crystal extracted (the latter has instantly knocked out everyone else. Including Usagi).
Huang Bu-ling from Tokyo Mew Mew, whose sprinting and flailing is often accompanied by circus tricks like running on top of a ball or breathing fire. As Mew Pudding, most of her fight scenes consist of jumping around and climbing things.
Nina from Tona Gura is so annoyingly Genki, she nearly causes Emotionless Girl Marie Kagura to punish her, something she never does to anyone outside of her brother Yuuji. In his Chivalrous Pervert mode, Yuuji asks that he be punished in her place. If Marie were to choose this option with Tojo Haya, like as not no one would stop her.
Minori from Toradora!. Approaches everything with so much energy that she makes the surrounding people look lifeless.
The first time we meet Sakura in Tsubasa Reservoir Chronicle, she jumps on Syaoran and rapidly asks him a series of questions about how he's doing.
Chizuru Sarashina from Wandering Son is a wacky and eccentric girl who does what she wants to, even going against her school's clothing rules (she wore a bikini instead of the school swimsuit once, sometimes wears a tie instead of a ribbon, and wears the boy's uniform occasionally).
Villain Mojo has a Deadpan Snarker assistant, Majordomo, who in turn has a Genki Girl assistant, Minordomo. Minor can be expected to say "Ohmygosh, OHmygolly..." at least twice per appearance, and will get worked up over something (complete with arm-waving and rapidfire talking — her version of it goes from sentences to short phrases strung together in the end) more and more until finally having a heart attack. Luckily, she's an artificial human, so Majordomo just has to hit her reset button to get her up and genki again.
Early appearances of Kitty Pryde started her out as a Genki Girl, though she actually matured during her run with the team.
Tania Gunadi in this Target commercial...and this Honda one.
"So much glitter!"
A Pikachu in Love gives us Pichi, a rather hyperactive Pikachu who, if not for her much nicer disposition and lacking of reality warping powers, could be mistaken for the Pikachu equivalent of Haruhi. Gets BRUTALLYDeconstructed later on when her wacky and carefree antics nearly get Pikachu killed by an Ursaring and cause her to suffer a Heroic BSOD due to feeling like it's all her fault. She gets over it a little as the fic goes on, but is noticeably a lot less carefree and perky for the rest of the fic.
Some Semblance of Meaning has the District Twelve tributes' escort/makeshift mentor, Lavinia Gilden ( also known as Tansy Leefinch), who is highly energetic and bubbly... although this lessens later on as Vale and Kit go into the Hunger Games and Lavinia has to watch them suffer in the arena.
In The Lunaverse, the character Pinkie Pie's Genki Girl qualities are deconstructed- far from her "Friends to everyone" quality that this grants her in canon, these traits make just as annoying as a Genki Girl would be in real life.
The Little Mermaid has Ariel, who frustrates her father with how energetic and adventurous she is. Years later when she's grown out of it, she ironically describes herself as "a real fish out of water".
Jessie from Toy Story 2 and 3. What we see of her Show Within a Show character is pure Genki; in her real-life personality, though she displays quite a bit of cynicism and remorse, she still manages to fit this trope.
Trixie the Triceratops from 3. Bonnie from the same film seems like she'll grow into one of these as well.
Young Ellie from Disney/Pixar's Up! is definitely one of these. Her wonderful mania for living makes you feel for her all the more when she finds that she can't have children.
Vanellope Von Schweetz from Wreck-It Ralph is certainly this. Considering that she's a game character from a Candy-themedRacing Game, it would be downright bizarre to have her be anything but hyperactive.
Kiina's portrayal in BIONICLE: The Legend Reborn qualify her as one. It's in stark contrast with how sour she behaved in the novel that takes place before the movie's events — however the movie was written first. It was also the only time we saw this side of hers, but it had already stained her image in the fans' minds.
The writer offered justification: one, she has every right to act that way in the movie considering the events, and two, according to the Novelization, she's something of a Stepford Smiler.
Princess Anna from Frozen is extremely hyperactive and impulsive to the point of being dangerously reckless, even at the age of five. Being all alone in a castle with nothing to do and no one to talk to for 13 years has only exacerbated this, to the point where her second "I Want" Song is damn near exhausting to watch.
Every role Bollywood actress Genelia D'Souza has done. Ever. Even in the non-Bollywood Indian movies. Her most famous Genki Girl role was in the Telugu film Bommarillu. It was remade into three different languages, and she played the same character in all of them.
Jordan: I never sleep, I don't know why. I had a roommate and I drove her nuts, I mean really nuts, they had to take her away in an ambulance and everything. But she's okay now, but she had to transfer to an easier schor I don't know if that had anything to do with being my fault. But listen, if you ever need to talk or you need help studying just let me know, 'cause I'm just a couple doors down from you guys and I never sleep, okay?
The eponymous character of Anne of Green Gables, who has a tendency to spout monologues lasting for more than a page. She stops this in the later books, though.
Andrew Vachss's Burke books have Pepper, although speaking to Burke somehow puts a damper on her energy.
Permanent Rose Casson from the Casson Family Series. She is described as recklessly boisterous (going so far as to cause a traffic jam just to meet a boy her brother knows - and she's only eight!) and when told that her father is going to New York, she about bursts with energetic excitement.
One of the first eccentricities Winterbourne notices about Daisy Miller is how she's just overflowing with energy and enthusiasm. "It was many years since he had heard a young girl talk so much."
The eponymous character of the Ramona Quimby series is rambunctious and noisy and described as "the cheerleader type" by her older sister. Her excitable nature has been known to clash with her friend Howie's stoic demeanor.
Birdie Boyer, the main character of Strawberry Girl.
Quite a few of Anne Tyler's heroines qualify, especially Pauline in The Amateur Marriage (one of the many reasons why she and her husband Michael are so mismatched). There's also Maggie in Breathing Lessons, Rebecca in Back When We Were Grown-Ups, Pearl and Jenny in Dinner at the Homesick Restaurant, and Muriel in A Patchwork Planet.
In the Rainbow Magic series, Addison the April Fool's Day Fairy is always bursting with excitement, and has to be reminded several times that she can't be spotted by other humans.
Nahruahn in The Quest of the Unaligned is a male version of this, due to the mental effects of his wind magic. His Establishing Character Moment comes when, upon being introduced to the hero, he gives an eleven-line monologue in a single sentence, without stopping to breathe.
Live Action TV
Rachael Ray from her eponymous talk show. She purposely avoids "sob stories" and almost always has a smile on her face. She also works 100-hour weeks and is a rather shrewd businesswoman, and her energy and determination are usually quoted as the source of her success.
Giada De Laurentis is a somewhat more sedate Genki Girl, also on Food Network. What probably helps is that, with that largish head and especially large eyes of hers, she even almost looks like a real-life anime girl. Or, to put it visually....◊
Sandra Lee, once again from Food Network... well, fits the "dosed up on caffeine" requirement at least.
Ingrid Hoffman is relatively sedate on her English-language show, but watch her in Spanish... it's like Rachael Ray raided Giada's closet.
Similarly, Ellen DeGeneres is very energetic.
Kat, who never seems bothered by her constant loss of memory from Alphas.
Momoyama Lily in the Japanese drama Anna-san no Omame (a.k.a The Best Friend of Beautiful Anna).
Daisy Wicke from Bones manages to pull it off by being endearing when she isn't being incredibly annoying.
This is a common trait on Coronation Street right from the first episode with Linda Chevski (which aired December 9 1960) to today's Kylie Platt. Combine this with Really Gets Around and you get one of the shows favourite archetypes the classic "Tart with a Heart".
Dharma from Dharma and Greg is the most energetic flower child you can imagine.
Cherry, particularly in her early appearances. When she first started work at the Mill, Michelle got her to put away all the medicine that had been left out, expecting to have to sort it out herself later. Not only did Cherry get it done in record time, while she was at it, she alphabetized all the cabinets to make things easier to find.
Elliot Reid was for the most part of the first few seasons highly enthusiastic and quick-talking, tempered with bouts of self doubt (audience: AWWWW!). Her enthusiasm was more of a mask. She was very neurotic on the inside, due to bad childhood experience, overbearing parents, etc. She could be considered a Genki Girl later on, the way she pushes her boyfriends about (sometimes literally). This is a case of Characterisation Marches On and Early Installment Weirdness. Elliot was initially portrayed as a competitive and smug know-it-all - her Genki tendencies didn't show up until the second season.
Played for Drama with Denise - a paramedic Dr Cox is forced to work with. She's eternally cheerful and babbles on and on about everything. Though it turns out her young son died in an accident years ago.
Claudia Donovan, a hyperactive, always-getting-into trouble techwiz from Warehouse 13.
Kang Jong Hee in Wild Romance is bipolar, so she goes through periods of excitability and depression. When she's happy, she's exceedingly happy and takes to biting people.
Mickie James, though she fit the bill more when she was playing her psycho character. Her entrance theme was a Suspiciously Similar Song version of "Hey Mickie" and she would literally bounce all the way to the ring. She calmed the bouncing down after her Heel-Face Turn, but still fit the trope.
AJ Lee when she was on NXT season 3. Overly perky and energetic and she once appropriately had to give a speech about caffeine. "Caffeine will perk you up, but I'm some natural dynamite baby".
Christy Hemme from the first Diva Search was like this, standing out as the only girl who actually had a lot of personality. Trish Stratus even told her with her winnings she could go buy herself some decaf. Christy responded "it's all natural".
Jessica James from the indie circuit and SHIMMER fame is like this as well. It rubbed off on her tag team partner Rachel Summerlynn when they formed Rachel And Jessica's Excellent Tag Team.
The appropriately named Amber Lively from Wrestlicious, the perky and fun loving cheerleader. What's hilarious is that the woman who plays her (Madison Rayne) is known for playing the exact opposite in TNA.
Canadian wrestler Jennifer Blake is in full on Genki mode whenever she works face. As a heel, not so much. It's still very appropriate that her nickname is "Girl Dynamite".
As a heel Layla El wavered between this and The Fool. After her Heel-Face Turn she was a proper Genki Girl. She would even enthusiastically kiss a child in the crowd during her entrance.
Rikku in Final Fantasy X. The sad over-tone of Final Fantasy X kept her Genki-ness down a bit (and despite that she's still eccentric and cheerful). In Final Fantasy X-2, she becomes Genki Girl incarnate.
Although perhaps not to the degree of her 'sisters', Penelo of Final Fantasy XII fills in this spot alongside Vaan in an otherwise very no-nonsense group.
Path of Radiance and Radiant Dawn have Mia, who is obsessed with finding her rival (a swordsperson in white) and dueling people at dawn.
Tiltyu from Genealogy of the Holy War is a tragic example of how a Genki Girl can eventually break down and cannot be Genki anymore for the rest of her life. Sylvia also counts, and for the second half Fee and Patty (and her replacement Daisy) more than fit the bill.
Deconstructed in the GTA Radio from Grand Theft Auto: Vice City, where Amy from the VCPR station is a Genki Girl who was put on heavy anti-depressants ever since her family was brutally murdered.
Year 2 of Grim Fandango features a minor character Lupe: a coat-check girl at the Calavera Cafe, who tends to get overly enthusiastic about her job. This is pointed out in a conversation between Manny and the police officer Carla, when the latter cites Lupe's presense as the reason she stopped visiting the cafe:
Carla: All that bubbly energy, I just want to strangle her!
Manny: I've tried that. It doesn't stop her.
Izuna from the two games sporting her name certainly qualifies.
Kula Diamond in all her hyper-cheery, candy-loving, Face Doodling glory. She's especially notable given her status as an Opposite-Sex Clone of the much more serious Kyo Kusanagi, and given that the same experiment that created her led to K.
Yuri Sakazaki becomes one of these later on. She's kinda like that in Art of Fighting 2 and definitely in the Capcom vs. SNK games
Mignon Beart from KOF Maximum Impact. Also, Athena Asamiya, Mai Shiranui, and Metal Slugcrossover Fiolina Germi.
King's Quest: Princess Rosella of Daventry is just as fond of adventuring as her dad, impulsive, fun-loving, and extroverted.
Kaori Nishidake. In a series about death-defying snowboarders, Kaori's excitable nature is explicitly childlike and she just has so much fun out on the snow.
Marisol Diez Delgado from Tricky also qualifies.
Saints Row: The Third's Genkibowl DLC 'Genki Girls' couldn't personify this trope any more than they already do. Angry Tiger, Sad Panda, and Sexy Kitten are high-energy fast talking costume wearing minions of the aptly-named Professor Genki.
Kunoichi in Samurai Warriors. Although she mixes an unhealthy amount of creepiness with it, what with her stalking Yukimura and enthusiastically suggesting the most dreadfully violent solutions to any problems that may pop up.
Many Suikoden characters are this; sometimes there are many in the same game. For example:
Miakis from Suikoden V, initially. Then she gets saddled with an overload of angst, but eventually reverts to form over the course of the rest of the game.
Nanami of Suikoden II. Her introduction sequence consists entirely of her shaking her brother around out of giddiness for about 2 minutes, culminating when she accidentally sends him hurtling into a cliff wall, leaving a hero-sized imprint in solid rock.
Norma Beatty in Tales of Legendia. She goes as far as giving her party members strange nicknames like Senny and Teach.
Arche from Tales of Phantasia starts off very much like this, though mellows considerably after the party visits the Elf Village, and her mother is seemingly executed in her place. Which, to be honest, is fairly understandable...
The Legend of Zelda: Skyward Sword. Apparently, she isn't above dragging her childhood friend around to things she wants to do, doing all the talking whenever she's around (even if Link never talks), and pushing/jumping at him from potentially-lethal flights to make him use the sailcloth/catch her on his Loftwing.
Touhou's Cirno is such a genki girl she gets an entire song in which to display it. "Chirumiru, chirumiru genki, chirumiru!" Marisa also displays levels of genkiness. What else would you expect from a Cute Witch that can fire a giant Wave Motion Gun?
Polly in Custom Robo Arena. At some point in the game, her battle cry in actually "I'm all hopped up on coffee!So I wont lose!".At another point she sends you to fetch her "The Legendary Coffee", to allow the player to fight her.After the player wins she asks:"Hmm... maybe all this coffee is stunting my growth?"
Hilde Wangel in The Master Builder of Henrik Ibsen is probably one of the oldest examples. She is irresponsible, playful, and clearly after amusement. And when she gets Solness to climb the highest tower, like she has urged him to, she can`t keep herself from jumping and waving her hat - and making him lose balance and fall to the ground in the process. Her reaction is more bewildered than guilt-ridden.
Pearl Fey in the second game. The trip to Kurain Village takes two hours by train. She ran all the way.
Ema Skye was this in her first appearance in the first game, being very enthusiastic about everything (though especially scientific things). She's less so in her reappearance in Apollo Justice, though.
Nelie and Orpha in Eien no Aselia. Nelie's twin Shiah looks like she's trying, but she's a little shy.
Hagino apparently has this role assigned to her in Canvas 2 and is required to be cheerful or Hiroki will get upset.
Da Capo II has Yuzu, one of the characters in Nanaka's route, who is as genki as they come, despite being an Ill Girl.
Ilya is too, except she's a genki not-quite-evil girl who likes dismembering Shirou a bit too much. Shirou also realizes after spending a little time with her that it's all an act and that in reality she's immensely conflicted inside about whether to treat Shirou as a brother or an usurper.
Tsuzuriko/Tojiko in Kara no Shoujo is your everyday genki girl, going to school at an academy full of near zombies. You might say she stands out a little.
From Katawa Shoujo, Emi and Misha. However, they are rather...interesting variants of the trope. The former, while she indeed is a cheery girl, it turns out she's not as drama (or trauma)-free as she initially seems. The loss of her legs was traumatic, but she learned to cope with that well. The loss of her dad she did not cope with at all. Part of getting her happy ending is to help her deal with her loss. And for the latter, it's partly a pretense to hide the emotional trauma of Shizune rejecting her love confession, as well as being a coping mechanism for said trauma.
Haruka from Little Busters!, oh so much. Constantly running around causing mischief? Penchant for broadcasting her emotions at the top of her lungs? Acts like she's incapable of being serious for ten seconds at a time? Check, check, and check. She has Hidden Depths, though - she's well aware that she's very noisy and feels awkward around people like Rin who can't deal with that, and can be quite savvy when she puts her mind to things. And, of course, the whole thing is covering up a very screwed up, insecure individual who has very, very good reasons for priding herself on causing commotions.
Sachi in Sharin No Kuni. Natsumi used to be one as well until she was accused of 'seducing' an upper class boy and receiving her obligation. Natsumi gets hers back at the end of Chapter 5 and keeps it in the fandisc
Tillie, the Team Mom of Ascension. Her relentless joie de vivre is frequently lampshaded by the other characters; The Heroine even refers to her as a "sugar-crazed alchemist dwarf". Proof: her reunion with The Heroine in the second chapter, in which she goes in for a big ol' glomp:
A comicallyAx-Crazy version — Bangladesh DuPree. Her first phrase in the comic is "Ta daa! I am here!" and on the next page she proclaims "Nobody knows more about torture than me!"... just as cheerfully.
Jade Harley of Homestuck, even her typing quirk is genki - omitting periods and overusing exclamation points and emoticons. Her Troll counterpart, Feferi, also tends to get overexcited about everything.
Beforus gives us Latula, who is constantly on the go and obsessed with being rad, and Meulin, a TumblrFangirl parody prone to overdramatic emotional declarations and gleeful shipping dedication.
Ivy from Lackadaisy is actually based off a hyperactive cat that the author knew.
Clau from M9 Girls! is always hyperactive and overly optimistic.
Asako from MegaTokyo is a Genki Girl of Mass Destruction, and her friend Mami knows the arming codes. As Mami says, "Hey, I always reserve the right to use the 'Asako option'. You should know that by now."
Missi from Misfile definitely qualifies. While not exactly hyper, she's drastically energetic and upbeat when compared to the rest of the cast. So far nothing, not even being dumped, has been able to make her sad for more than a single panel.
Sapphire from Monsterful: The energetic zombie teenager is way faster and louder than a zombie should be.
Suzy from Paranatural is a journalist version of this. Every time she appears, often or always around her "willing" assistant Collin, she's doing something over the top and insane. This mostly involves trying to get the main character Max to join the Journalism club at the school. Or blackmail. And in the spinoff sections called "Supernormal" she has a single appearance that further cements the evidence she's slightly off... and a fan of circular journalism. See it here.◊
RWBY: Nora is an energetic non-stop talker who doesn't appear to have an off-switch even at the crack of dawn. She's even accompanied by her own unique zany music score for when she really gets going. It contrasts with her partner Ren who needs to be kicked out of bed in the morning and who barely talks. Not even cleaning teeth or eating breakfast slows her down. The quietest and most still she gets is when the Headmaster is explaining their first task, but she even interrupts him on one occasion and can be seen in the background bouncing energetically on her heels as she waits for the task to begin. Ren seems to tolerate her energy and Motor Mouth with good humour and affection.
Pistol on Goof Troop is constantly hyper. As her neighbor Max put it once, "watching Pistol is like nailing Jell-O to a tree." Playing with her is considered a nuisance at best and outright torture at worst, and if they can, people try to avoid the task or pass it on to others, usually stopping at Extreme Doormat PJ unless he manages to hide. It's fairly surprising, considering that her father is very lazy and her mother and brother take turns being the Only Sane Man.
Mabel Pines from Gravity Falls is loud, playful, and enthusiastic about just about everything ("Yay, grass!").
June from KaBlam! started out as one of these, as well as The Ditz. In season two, she's still this trope at times, but much more snarky. In season three, this starts to drop a little bit more as she becomes a sarcastic Jerkass, and by season four, this is gone and she became a slight example of the only sane girl.
"Party of One" explores (and later deconstructs) this: There is a limit to her energy but it is significantly higher than everyone else's. Then you watch her get angry and find out her energy can be used for more than just bouncing happily...
"Too Many Pinkies" has Pinkie inadvertently creating an unruly horde of Flanderized clones of herself. Her friends, used to Pinkie embodying this trope, can't tell the difference between the mindless clones who constantly spout "FUN!" and the real Pinkie. This causes Pinkie to have an existential crisis and seriously consider the possibility that she's just a clone who thinks she's real.
The Cutie Mark Crusaders are an entire group of these. They tend to egg each other on.
Rainbow Dash surprisingly counts as well especially in recent episodes with her excitement over the new "Daring Do" book and the Equestria Games. In the latter, she flat out channels Pinkie Pie for the whole episode.
From the original My Little Pony we have Surprise, whom Pinkie is heavily based off in FIM. She enjoys pranking people, is very active, and is very loud.
My Little Pony G3 Pinkie Pie wasn't quite as madcap as her FIM version, but loved parties and was obsessed with the color pink.
Teen Titans: Starfire's powers manifest from unleashing her emotions. (Although all evidence suggests that anger worksbetter in a fight. In the first episode we learn anything about it, she cheerily explains that her starbolts require "righteous fury".)
Uniqua from The Backyardigans is one of those. But in one episode, usually-Tsundere Tasha got to be the Genki Girl and show her deredere side.
The eponymous (title) character of The Mighty B!, Bessie Higgenbottom, is an ambitious and optimistic 9 year old Honeybee scout who believes she will become a superhero called The Mighty B if she collects every Honeybee badge.
Transformers Prime: Miko, who transferred to an American school to escape a life of piano lessons and ends up in the middle of a war between alien robots, to her absolute delight. Also played by above mentioned Tania Gunadi, who is good at these.
Kristen Schaal seems to have forged an entire career out of playing Genki girls. Her real life persona is slightly less Genki than her various animated ones, though not by much.
Hayley Williams of Paramore, so, so much, if the way she answers interviews, tweets, and acts on stage is anything to go by. Not many people would Tweet about how much underwear they're going to buy or make jokes about their own chest during an interview.
Grey DeLisle. Some of the characters seen in the "Western Animation" section were voiced by her. That cannot be a coincidence.
Japanese singer and actress Tomoe Shinohara. "Mikakuru-kuru-kuru-kuru-kuru-kuru ~!"
WWE's ring announcer Lilian Garcia, as a glance at her web show with Torrie Wilson and Candice Michelle will demonstrate. It rubbed off on actress Maria Menounos when she guest starred. Unless she was waving beer cans and asking the others to feel how warm her chest was just to impress "Stone Cold" Steve Austin...
Delta Goodrem can barely sit still during her interviews and appears to be endlessly bright and cheery.
Rebecca Knox is like this in real life. In the ring, not so much.
Kakeru, The Protagonist of Area no Kishi, is a student who channels his love of football into working tirelessly first as manager for his high school football team, and later in the series to overcome obstacles becoming a player himself.
Just like Taiwan is the Genki Girl from the Asian Group in Axis Powers Hetalia, her "brother" South Korea fits the bill.
Bleach: Asano Keigo is constantly active and cheerful (or entirely down in the dumps), to the point that he gets on Ichigo's nerves. Though he does have some introspective moments, they are few and far between.
Jackie Gudelhian, Johji Ohtomo and Bleed Kaga from Future GPX Cyber Formula are adult versions of the trope. The latter, however, drops off his genki-ness in the ZERO arc when he began to become serious.
Most of the Robins have this to some extent, although this was most obvious in Golden Age Robin (which was translated into that of the TV series.)
Because of his accelerated perception of time, Quicksilver from X-Men: Days of Future Past, seems to get bored easily. Xavier calls him a pain in the ass because he refuses to stay still, running circles around his guests and generally amusing himself at their expense.
Jeko from the Col Sec Trilogy is a small, wiry, hyperactive young man who's always trying to rile the resident Tsundere. (On an off note, although it's not anime, it's mentioned at one point that he's Japanese-American.) Enough said.
Beetle Bailey's Asian Token Minority character Corporal Yo sometimes has the trait of getting really, really excited about anything he finds interesting, and he likes to run around doing everything as quickly and efficiently as possible.
Bartz from Final Fantasy V is the first protagonist to start a trend of cheerful heroes throughout the series.
Zell from Final Fantasy VIII whose character introduction is literally him backfipping into the room. He apparently used to zoom down the hallways on a hovering skateboard and has been known to throw really aggressive tantrums when the cafeteria is out of hotdogs. Adding to the effect, he also talks like he's Pretty Fly for a White Guy.
Zidane of Final Fantasy IX overlaps with The Casanova. His Genki side really comes out whenever he's trying to woo the princess. It's no surprise that Eiko (mentioned above) develops a crush on him.
Tidus from Final Fantasy X certainly fits. Our first proper impression of him is enthusiastically signing autographs for his fans and he manages to shock all the people of Spira with his attitude. Lulu remarks "you really do come from a world where there is no Sin" after having experienced a few weeks with him. Surprise surprise, him and Rikku (mentioned above) are Like Brother and Sister.
Vaan of Final Fantasy XII fills in this spot alongside Penelo in an otherwise very no-nonsense group.
Normally, Elliot from El Goonish Shive doesn't qualify for this trope. But he can shapeshift into various female forms, a few of which have their own personalities. There's one called the "Party Girl Form," which is Elliot on a shapeshifting Gender Bender, with a Motor Mouth and Elliot feeling like he just downed a hundred shots of espresso. Appropriately, since this form and personality is so radically different from Elliot's own, this form has been dubbed "Heidi," as it's the closest name to "Hyde".
"Heidi" actually originated from another character being caught trying to warn party-Elliot to "hide" note he'd just been fighting monsters as a sexy superheroine, and the party girl form is supposed to be a secret identity and covering it up by pretending it was the party girl's name. The false etymology of "Hyde" still fits, though.
Mulder turns into Genki Guy in Monster of the Week. It's visible from the very first panel, although he gets calmer as the series progresses.
Aang from Avatar: The Last Airbender is—when not having to save the world—cheerfully energetic and quite confident. He provides a contrast to the other guys in his group: snarky Sokka and brooding Zuko.
Odd Della Robbia in Code Lyoko has plenty of energy and confidence. And his Lyoko Warrior form is cat-based.
Marty Lublin, the traveling host at Wheel of Fortune auditions. He is fond of jumping around the stage and yelling. The show wants enthusiastic contestants, so why not get a very energetic guy to determine if they're good enough for the show?