OC Stand In / Western Animation

• In Jackie Chan Adventures fanfiction, especially the group of fics known as Project Dark Jade (Queen of All Oni and Queen of Shadows are prominent), this is common for the Oni Generals minus Ikazuki. They aren't even named in canon! The Queen of the Shadowkhan, Jade's Superpowered Evil Side that appeared in one episode also sometimes gets this as well, albeit to a lesser extent unless the story is very AU.
• Phineas and Ferb:
  • Until episodes such as "Isabella and the Temple of Sap", the Fireside Girls had close to no lines and no characterization, other than Gretchen, who even then only spoke once or twice. Especially Gretchen, who in fanon is often paired with Ferb, apparently just because she's the first girl his age (other than Isabella) to get a name.
  • Django counts as well. He's been used a lot more by fans than in the canon series.
• Total Drama:
  • Ezekiel gets this fairly often. He got very little development because he was the first character to get voted off in both seasons he participated in. The Total Drama Comeback Series is often credited with popularizing this for him, since many of his characterizations in fanfics borrow traits of his depiction in that series.
  • Katie and Sadie also get this, since in canon aside from their co-dependency they have very little that separates them from the more developed and funnier Lindsay.
  • One episode of All-Stars features Scott mentioning his sister, a pig-calling champion named Alberta (who apparently prefers to go by Al). It's become increasingly common among TD fanfiction writers to give Al a full-blown personality and develop her relationship with Scott.
  • B also sometimes gets this treatment. Mostly due to his cool inventions and the fact that he never talks.
  • Beardo also gets this treatment occasionally. Despite being the first voted off in his only appearing season, he is often given larger roles in fanfics and tends to speak more frequently in them (while still keeping his signature vocal abilities).
• Invader Zim:
  • In canon, Gretchen was strongly hinted to have a crush on Dib in one episode. The pairing is not widely popular (despite being the only romance in an otherwise No Hugging, No Kissing series), but even those who don't use her as a main character often elevate her to "Most Important Random Skoolkid" or mention her and Dib's "romance" in passing.
  • Another commonly used character is Invader Tenn; she only shows up in two scenes in one episode, and it was planned for her to return in the never developed series finale. Because of this, she is very often often used whenever a writer wants or needs to use an Irken outside the ones with more screen time (Zim, the Tallest, Tak, Skoodge). Of course, most of the stories she shows up in are based on (or are outright fan versions) of the aforementioned finale.
  • Zita is another victim to this. While a girl with her looks is common to see in the episodes, all we know about her is that she considers Dib to be crazy and, unlike other students, is respected by Ms. Bitters and have the most moments of sympathy for Zim. Nevertheless, people throw even this minor canon out of the window and pair her up with Dib.
• The Metalocalypse fandom has Klokateers. In the show, they're several legions of hooded, uniformed, fanatically loyal employees of the Dethklok company who rarely have lines and are referred to by number rather than name. Because of the extremely stringent entrance exam and its 50+% mortality rate, the recruits who survive to become Klokateers are extremely exceptional specimens, physically and intellectually. This makes them ripe for this trope. There are a few who have risen to prominence, mostly through slash fandom.
• Daria fandom is pretty notorious for this, largely due to the fact that the show has scads of random recurring backgrounders who never do anything and yet have extremely distinctive character designs (a result of them all being based on real people who worked at MTV at the time). Because the fandom is relatively close-knit, the characterizations of many backgrounders have actually become pretty standardized. Burnout Girl is almost always involved with drugs, that blond from The Invitation is named Tori Jericho & was president of the Fashion Club before Sandi, etc.
• This is common in the My Little Pony: Friendship Is Magic community, due to the prevalence of Ensemble Darkponies:
  • Special mention goes to Princess Luna. When she first appeared, she had somewhat of a vague characterization, but she had barely any screen time or lines (excluding her Superpowered Evil Side Nightmare Moon). She then proceeded to vanish from the show for the rest of the first season. This prompted not only heavy speculation about her character (typically interpreted as a Shrinking Violet desperately trying to adapt to a world that's changed in the 1000 years she was gone) but also about what she was doing now (an oddly popular hypothesis had it that she was being politically repressed by her evil power-hungry sister, Princess Celestia). When she finally appeared in Season 2, she left this trope behind by simultaneously confirming AND contradicting nearly every fan depiction of her.
  • Thanks to being a baby, Princess Flurry Heart has been subject to all manner of interpretations to what her character would be when older, be it aloof, Nice Girl, Spoiled Brat, Spoiled Sweet, The Ace, Broken Ace, villain, or any combination.
  • Because of the huge Periphery Demographic that follows this show, many of the background characters have Word of Dante-style personalities that are almost universally followed. Even before the show canonized these personalities with the episode "Slice of Life", EQUESTRIA GIRLS, and the comic series, the fanbase as a whole decided that Octavia couldn't be anything other than a cultured, sophisticated character with a British accent or that Vinyl Scratch must be a wild unpredictable party animal, and the two characters were at least friendly rivals at worst and lovers at best. Keep in mind that these characterizations were put in place as early as the show's second season, at a point where these two characters had no lines and no interactions whatsoever on the show, never even appeared in the same episodes, and wouldn't for another three seasons.^note Even then, Vinyl was rendered as being mute, possibly to avoid dealing with the fact that the character has an official fanon voice actress. They're only two examples: almost every background character ever has been given a backstory and varying levels of characterization by the fans, and like Octavia and Vinyl, some are popular enough that it is considered Fandom Heresy to go against them. The most prominent are Lyra (Heartstrings), Bon Bon/Sweetie Drops, Vinyl Scratch/DJ-Pon3, Octavia, Derpy Hooves/Ditzy Doo/Muffins, Golden Harvest/Carrot Top, Time Turner/Doctor Hooves, Colgate/Minuette, Berry Punch/Berryshine, and Caramel. One particularly infamous example, aside from Derpy, is Button Mash, who literally had only a second of screentime in the episode before someone made a five-minute animated short about the character and his mother, which in turn inspired even more fanworks about them.
• Avatar: The Last Airbender:
  • Ursa, Zuko and Azula's Missing Mom. She's of no small importance to the plot, given that she killed Azulon to save Zuko's life, but her only scenes are in Zuko's flashbacks and Azula's hallucinations. Fans had a field day discussing how accurate either of those are and what she was actually like. It doesn't help that the lack of a family reunion was the series' biggest unresolved plot thread. She was eventually expanded upon in the comics released post-series, though not without significant controversy.
  • Lu Ten, Iroh's son who died in the first attack on Ba Sing Se, has practically no characterization in-series, being a Posthumous Character with no flashback appearances, so fans can project whatever personality traits they want onto him.
  • In the Sequel Series The Legend of Korra, another lady in the family gets this treatment, Zuko's unnamed, unseen granddaughter. In the commentary for the fourth season, the writers confirmed that Fire Lord Izumi (Zuko's daughter) was supposed to have a bigger role in the story but they got an episode cut out of the budget at the last minute and she just didn't have a place in an Earth Kingdom based story. She was going to spend more time in Republic City and her daughter was going to come with her. They even toyed with the idea of making her Mako's Love Interest but decided they didn't want to put him in another relationship. They even told people to write fanfic about it and now unnamed Fire Nation Princess (usually named "Ursa" as a Dead Guy Junior Family Theme Naming with her brother Iroh) is Mako's standard love interest in fanworks even though no one knows anything about her.
• Danny Phantom: Given there are several students at Casper High who don't even have names, there are many characters the Phandom likes to use in place of standard original characters.
  • None are as so popular as Star, or Star "Satellite" as the fandom has named her. She has some lines and establishing character moments, but in general the series portrays her as the blonde girl who hangs around Paulina. Naturally, fanfic authors have a ball giving her Hidden Depths, usually making her a love interest for Danny.
  • Wes Weston is the name given to a background character who only appeared in "Shades of Gray". He was given the name based on a Running Gag from another episode, and characterized as being the only person in Amity Park to realize that Danny Fenton is Danny Phantom. Stories with the character have him frustrated that people not only don't believe him, but think he's the ghost kid instead. He is now considered the Phandom's group Original Character.
    • The Phandom also gave Wes a family in the form of two other minor characters: a brother named Kyle (who also knows Danny's secret identity, but doesn't believe that ghosts exist and (depending on the writer) buys into several other "doesn't exist" conspiracy theories) and a father named Walter (the guy who wishes for wealth in "What You Want", generally depicted as working for Vlad Masters and desiring more cash).
• Take Care Bear is an unusual case. Her author created Take Care Bear as a custom bear, not one of the canon Care Bears, then inserted her into the world of the 1980s cartoon. This bear is a medical doctor, and her tummy symbol is an apple. Few fans knew that an official bear had the same name. Take Care Bear is a One-Shot Character in The Care Bears And The Big Sneeze, an obscure coloring book from 1987. This bear is a medical doctor, and her tummy symbol is an apple. (The 2004 toy line launched a new version of Take Care Bear.)
  
  The similarity might be coincidence: "take care" is an idiom, and there is a proverb, "An apple a day keeps the doctor away." So it is plausible that the fan author, not aware of the coloring book, created a custom bear with the same name, job, and tummy symbol. The coloring-book bear has brown fur, but the fan-fiction bear has red fur. Fans may conflate two into one. Therefore, the fan-fiction Take Care Bear is an OC Stand-in for the coloring-book bear.
• Part of the South Park fandom will utilize this trope on minor classmates in the 4th grade class. Red was a popular choice in early years, as she was the only one of the girls to have had no lines or discernable personality – up until season 6 and on. Kevin Stoley is the usual favorite these days, with fans attempting to give him an entire backstory beyond being the Star Trek/Star Wars geek and theorizing at length about his relationships and family.
• In the later seasons of The Raccoons, an unnamed little raccoon girl made several silent cameos, and got one speaking role in the episode "Endless Summer!", where we briefly see her talking with Bentley. She has seen use by many fan-fiction writers, usually giving her the name Annie Ringtail (with some writers naming her Penny). A great deal of these fan-fictions depict her as a love interest for Bentley, though how he returns the affection (if at all) varies by writer.
• X-Men: Evolution:
  • This show is an unusual case, as it's not so much characters from the show who are stand-ins, but the characters not featured. Due to the series tweaking some personalities to make them teenagers (some who all they share with their original versions being their names and some don't even get their real names, just their old codenames), a lot of characters from the comics that the show was based on work as these. Want a female British X-Man? Covered, Betsy Braddock/Psylocke will work. Want a male British one? Pete Wisdom. Want a team genius? Cypher. Want a character with a Dark and Troubled Past? Its X-Men, anyone would fit that.
  • Dani Moonstar and some of the New Recruits serve as this as well. As Dani only appeared in one episode, not much of her personality was fleshed out, and as such can serve as any personality type they want. Roberto only got a bit of characterization: A slightly egotistical 'jock' type, while Rahne got a snarky playful personality, both from just one episode, after that, they get no lines other than background appearances.
• Charlene from Alvin and the Chipmunks is presumed to be a prototypical version of Brittany. She only only officially appeared in one song (though an unnamed chipmunk in several later music videos looks like her). Nothing is known about her in canon besides she liked Alvin (and Alvin liked her back). She frequently appears in fan-works nevertheless.
• Miraculous Ladybug:
  • The original "pilot" short for the series had a character named Félix (or Felix) as Chat Noir; though he superficially resembles Adrien, including having a Two Person Love Square with Marinette, he was much less friendly toward her. Word of God says he wasn't working, so they scrapped him and made Adrien instead. In fanfic, however, don't be surprised if Félix shows up as Adrien's Aloof Big Brother or Polar Opposite Twin, who may have been the previous Chat Noir or currently be splitting duties with him. (His continued popular eventually got him an appearance in the show as Adrien's Jerkass Woobie cousin.)
  • Similarly, the slightly-different design of Marinette is sometimes made into a whole new person named Bridgitte/Bridgette, who may be Marinette's sister or cousin.
  • There’s also the other young superheroes (Melodie, Mercury, Kid Mime, and Sparrow) that ended up being scrapped when the creators decided to just have Ladybug and Chat Noir be a duo. Fanfic writers have a ball coming up with personalities for them and guessing what sort of bonds they would have with Bridgette and Felix.
• Gravity Falls has a few notable examples:
  • Tad Strange, before he actually appeared, his Punny Name, voice actor, and comments about him being "a real square" led to the fan theory that he would be a second dream demon similar to the triangular Bill Cipher. Fans doubled down on this when the creator, known for his Trolling Creator status, tried to warn them that they were making a big deal out of nothing. The warning proved to be true however, when it turned out he was a one-off joke about a Ridiculously Average Guy with an Ironic Name. Demon!Tad still shows up in fanfic sometimes, occasionally under the new name Dot Matrix, and may be combined with the canon version.
  • Jimmy Snakes, a character from an unused episode mentioned by Alex Hirsch on Twitter. He was supposed to be a former friend of Stan who had become a Ghost Rider-like entity, and a concept drawing showed him spitting in Stan's direction. Popular fanon diverges on his portrayal; he's frequently an Old Flame of Stan's, but whether he's abusive or simply rough around the edges depends on the author.
• Lydia from Milo Murphy's Law, about whom we know little except that she's a friend of Amanda and (to a lesser extent) Melissa. She seems like a nice kid, which makes her ideal ship fodder.
• Maiden Goldenwaves and Maiden Mistycurls were never featured in the Lady Lovely Locks cartoon. Their only known backstory is that Goldenwaves lives on the Enchanted Island while Mistycurls visited it looking for the Sea Pixietails, the Sea Pixietails can turn them both into mermaids, and Lady and the other maidens discovered the island with the help of the Hide 'n' Peeks. Much of this backstory is only related in the toyline's press kit, and their personalities remain a mystery.
• Stacey, Larry's girlfriend from Life With Loopy is this for the shows fans, being an Ensemble Dark Horse who appeared for less than a minute at the end of her only episode (which also happened to be one of the last few episodes), leading her to not evolve past a Satellite Love Interest in canon. With fans, she's often depicted as being nerdy, a bit awkward but better adjusted compared to Larry, and often the "middle ground" between Loopy's idealism and Larry's cynicism.
• In Steven Universe, many of the Gems are foreshadowed by an off-handed mention or an Early-Bird Cameo. However, as of the finale of Steven Universe: Future, some of them ended up never making a proper appearance, allowing fans to fill in the blanks themselves.
  • Of particular note is Morganite, the former owner of Rhodonite's components, who discarded and replaced them after seeing them fuse. Outside of that and being most likely a pink Gem with a chest placement and most likely under Pink Diamond's Court, that's all we know about her. Many speculated that the Gem in the teaser for Steven Universe: The Movie is Morganite, or at least of the same type, due to the same Gem placement and color, but she turned out to be a completely different character named "Spinel".
  • The Citrines. Mentioned off-handedly in "Lars Of The Stars". They are Quartzes, they are yellow, they work for Emerald. That's all we know about them, everything else is up to the fans.
  • While most of the former Crystal Gem characters (such as Crazy Lace, Biggs, Snowflake and Little Larimar) do make an appearance late in the series, others (like Tiger's Eye, Beryl and Serpentine) never appear in person. Though many assume that Tiger's Eye is Crazy Lace's eye component, and the others are confirmed to be alive since they are bubbled and presumably corrupted, which is a non-issue in the current timeline.
  • In fact, many of the uncorrupted Gems qualify, since their characterization doesn't go far beyond being background decoration. Even the corrupted Gems qualify, due to their interesting designs and people love speculating just who they were before The Corruption.
  • In terms of human characters, the Mystery Girl from "Last One Out of Beach City" has been subject to this despite only making a major appearance in that episode and not even getting lines or a name.
• The Simpsons:
  • Francesca Terwilliger only shows up twice: once in "The Italian Bob" and once in "Funeral For a Fiend". All we really know about her is that she's Italian, she's Sideshow Bob's wife, and she has a malicious streak. However, since Sideshow Bob is an Ensemble Dark Horse and an insanely popular subject of Simpsons fan works, many fans of Sideshow Bob will incorporate Francesca into their fan works somehow and flesh her out into a fully realized character, because they find the idea of Sideshow Bob in love to be so goddamn cute. It helps that Sideshow Bob has a massive Estrogen Brigade who use his marriage to Francesca as a conduit to write about their fantasies of being married to Sideshow Bob.
  • In Flash Forward Fics, the Nahasapeemapetilon octuplets are a prime target for fan interpretation. On the show, they don't have much in the way of personality (being babies and all), and they basically function as a unit. Naturally, this leads a lot of fans to speculate what may happen when they're a little older, and how their personalities might diverge from each other. People who make Fan-Created Offspring for their favorite Simpsons characters or ships will probably have one of the octuplets as a friend of their OC.

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