I once wrote a ''{{Stargate SG-1}}'' fanfic with one of the side characters being Melia, an Ancient whose total canon appearances were two ''StargateAtlantis'' episodes, including the pilot where she was a purely expository hologram. My take was basically a quirky, hyperactive female version of the Doctor.

Except for the female part that was pretty much redundant.

This troper and her two fellow fanfic writing friends ADORE this trope; every single thing we ever do focuses on minor characters, some of them so obscure that they don't even have ''names''. Of meaningful note is Dura Lex Sed Lex (Friend #1), Express Yourself (Friend #2), and my ChuChuRocket fanfic, We Love You Anyway.

This Troper is using the {{One Piece}} filler character Tajio from the Post-Alabasta episode about the curry as one of the members of her crew.

Blunderbuss: Oh man, they are not ''kidding'' when they say MegaManX is sparse on characterization in the early games. The general who leads the Maverick Hunters in X3 and X4 is never actually named, nor do we even know if they're a reploid or ''anything'' about them. Not only that, but humanity ''itself'' is practically an OCStandIn, since humans are barely even mentioned. I decided to kill two birds with one stone and create Edmund Bauer, General Commander of the Maverick Hunters. (I also decided to name that pink-haired navi in MHX Circa, and actually give her a personality.)

In a Pokémon fic this troper is writing, he managed to apply both this and AuthorAvatar to one character, due to the fact the character shares his name.

These are this troper's guilty pleasure. Character needs depth and I need a story? Bam.

This troper has done this with one of the criminally under-used Pirate Lords from the third PiratesOfTheCaribbean movie. He's only in one scene since it's a Disney crossover where mostly animated movie characters show up, but he gets to have at least a little more characterization than the movie.

I seem to have a problem with this: most of the RP characters I use have little to no personality in the work they appear in and forge a completely new one. Case in point: Czernobog and the Dullahan.