Forgettable Character

Memories of families and friends are a wonderful thing, though there are times when a character is missing or rather forgotten, even the whole world, universe, alternate reality forgets that a character exists as though the character in question wasn't born, when this happens this is a forgotten character. Sometimes a character wants to be forgotten to not imperil others, so his or her foes would not harm them in any way shape or form, so he leaves his family and friends. An Up to Eleven example, is that the character in question didn't exist at all, it does not explain all the interactions and stopping the fate of the world ending earlier.

The milder examples are that the character is insanely mundane that no one remembers him, especially if the world he lives in is fantastical or a world populated with superheroes and villains. The latter sometimes contain those that are being overshadowed by the Big Bad, the superheroes finds this minor villain as too easy to defeat that to the point that it's easy to forget about this character's existence and later on the heroes go "Who is this guy again?" When minor villains returns. In fantasy and Fantasy Kitchen Sink settings, a character's existence gets erase by very powerful spells, laser rays that have right or Gone Horribly Wrong.

The only way to prevent family, friends, and the heroes to fool proof this trope from happening is to have a backup spells, artifacts, clues, and even self notes to prevent this from happening.

Please note that this trope is mainly for in-universe only. The meta examples go to Out of Focus.

Compare and contrast with Ret-Gone, Ghost Memory, Unperson, I Was Never Here, Laser Guided Amnesia, Canon Discontinuity, and Fake Memories. For the more mundane types of Forgettable Characters, compare Those Two Guys.

Anime and Manga

 * Canada of the Axis Powers Hetalia series, the interactions that he had with other characters usually involved them forgetting who he was, his existence, or worst, mistaking him for North America.
 * Jewelpet Sunshine had three examples, Nejikawa who was forgotten by his classmates at least once. Yaginuma was a debatable case, because of his limited screen time. And Katori, whose peers keep on forgetting that she's there, because she's tiny.
 * Tetsuo Ishimaru of Eyeshield 21, were his teammates keep on forgetting that he exists. Tetsuo even breaks the fourth wall just to comment on this.
 * In Saki, this trope was nearly a superpower to Momoko Touyoko. She's invisible to anyone in the vicinity, since she barely leaves an impression. There's was even an incident when she was playing Mahjong with three players, but they've forgotten that she's there despite that she is sitting next to her.
 * In Sayonara Zetsubo Sensei, despite being the Class Representative, Kagero Usui had a property to just slip away from the other characters' memories. Just because his Prematurely Bald head was his only distinctive feature. - He takes great pains to hide most of the time.

Film

 * In Office Space, no one noticed that Milton, the quiet office drone, was gone. Also, for several years before he was actually fired from the company, to top it all off, was that everybody forgotten to tell him the news. Also, Milton continues to work there with no employment file, because the payroll system glitched and continues to send him his monthly salary (No one even noticed this as well).
 * Randy from Liar Liar, whom Fletcher Reede doesn't even bother to try remembering.

Literature

 * In Harry Potter, Peter Pettigrew (aka Wormtail) was known as the quiet yet unassuming guy in the Marauders gang. Also the fact that he was killed supposedly by Sirius, yet no evidence besides that. This trait was what made him be trusted by Sirius with the Potter family secrets and
 * In Blindsight, the Captain was this trope. It's so bad that the protagonist treats this as a huge reveal that the Captain was in charge (It's no secret that the Captain was an AI, plus the protagonist is a walking Sherlock Scanner, who forgets the Captain's existance since it doesn't leave any clues).
 * In Vlad Taltos, Kragar was just utterly forgettable that no one will notice him, even though he's standing in the same room, speaking to them, and hasn't moved.
 * In the novel, Nobody (By Jennifer Lynn Barnes), had the Nobodies, the titular group, needs a timer to remind them who they are looking for in case when one of them goes rogue. Since this trope is their biggest power and weakness.

Live-Action Television

 * In Buffy the Vampire Slayer's sixth season, the Terrible Trio which consists of Jonathan, Warren, and Andrew, who was a new character. The creators wanted to add Tucker as the third member, but his actor can't be contacted. This played a part in making the character of Andrew as Tucker's younger brother who has similar powers, and was gone when he summoned flying monkeys to attack the school. By Buffy standards, this incident was totally mundane that none of the cast remembers it or Andrew, now it's a gag to refer to him as "The other guy" or "Tucker's brother."
 * In Doctor Who had the alien race known as the Silence, who had the power to invoke this trope. The minute a person or different alien turns away from one of them, their existence were forgotten. They're instantly remembered the next time when the same person lays eyes on them again. This was seen as the Silence using this for infiltration, though their original purpose was
 * Torchwood had a similar villain who was in real danger of dying if they were forgotten, so they did everything they could do to avert this trope by forcing people to remember them..
 * In Arrested Development, not one of the Bluth family (except for George-Michal, the sometimes boyfriend) remembers Ann Veal's real name; they usually refer to her as "Bland," "Egg," "Annabell," "Yam," or "Her?" It's not done out of malice, it's just that Ann Veal was so forgettable.
 * In Friends, both of Ross's parents forgotten about Ben, since they were gushing over Emma.

Theater

 * In "Of Thee I Sing"'s Alexander Throttlebottom, the Vice Presidential nominee, who was running with John P. Wintergreen. The fact that Alex was so forgettable to the point, that he had to sneak into the White House while a tour was going on, since no one remembered him. (Back then when the play was written in 1930s, the VP position was infamous for its lack of notability.) Though he's remembered in the grand finale, mainly for Pair the Spares reasons.

Video Games

 * The Princess from Sakura Samurai had her royal subjects forgot about her and her own existence (Except for the friendly kappa that the player talks to). Justified since she was kidnap.
 * In some of the Mario games, Mario's younger twin, Luigi, suffers from this occasionally. Like in the Super Mario 64 DS remake, the Toads honestly admitted in front of him that he's not as memorable as Mario.
 * The Ace Attorney games had Winston Payne. In the past, he was fear as a rookie murderer, now Payne was unremarkable that most of the characters forgotten just who he was. Even when Detective Gumshoe just mentions him to Miles Edgeworth, one of Payne's fellow prosecutors (Who Payne insists that he mentored when Miles was younger), now Edgeworth assumes that Winston was just one of the janitors.
 * In Fire Emblem Awakening, there's Kellam and this trope was Lampshaded in his support conversations constantly and showing up in the gameplay: one would've never guessed that he'd be reclass into an Assassin.

Western Animation

 * In The Simpsons, there's many examples, like:
 * The Running Gag which had Mr. Burns forgetting who Homer was, though this was dropped mostly in later seasons.
 * Homer just as often forgetting about Maggie. Sometimes referring her just as "the baby", other times forgetting about her completely.
 * In Futurama, the running gag was that Scruffy had to reintroducing himself to people. Just to the point that "I'm Scruffy, the Janitor" also became his Catch Phrase. In addition, the other characters are just as forgettable to him, since he doesn't remember them either.
 * In South Park, "The Last of the Meheecans" episode, where the boys play a Border Control rpg, and the Mexican side won. It takes a long time, until Cartman realizes they forgotten about Butters (and even then only because he can win as the Texan side). The others wonder how this happened, Craig reminds them that Butters is easily forgettable.
 * In As Told by Ginger, Noelle was chosen to test the vanishing powder, mainly because she was not significant to miss. This was subverted later on, when it's reveal that Noelle is a cool cloudcuckoolander (by their standards) and became an Ascended Extra with more substance.

Web Comics

 * This trope happens often in Scandinavia and The World, one example was Denmark, who always forgets about the Faroe Islands, his own room mate exists...Also, the guy owes him money. Also, Norway is apparently oblivious to Kven, even if the guy is right in front of him.
 * In 70-Seas's side-story was centered around a "forgettable" character. During a bid for attention, he committed burglary and was arrested, even doing that doesn't work, and to top it all off, he was released. Never mind that he ''dropped" a stolen diamond in front of the police.

Real Life

 * Too many historical figures are lost to history's pages, since they're not named, recorded, and such. Even though a few managed to do something the current day remembers them for.