Used in Haunted Mansion and the Hatbox Ghost, as the vague backstory of the original Haunted Mansion ride had to be fixed to be a convenient setting; and what better way to achieve that than to decide that the canon of the stories would be the headcanons of the authors of the fanfics?
It's commonly accepted among the readers of Advice and Trust that Kaworu is a masochist, since he finds Rei to be beautiful when she's angry at him. The author has shot down this theory, but that doesn't stop him from putting in stuff like this:
Rei: I have slapped you, yelled at you, and I threaten to kill you in practically every conversation we have ever had, and this turns you on?
For no very clear reason, the Dragon Age: Inquisition fandom has given the name of Jim to the hapless scout who interrupts the first kiss between Cullen and a romanced female Inquisitor. This gets a nod in All This Sh*t is Twice as Weird, where Jim is the central figure in chapter 19 and is shown to have a propensity for stumbling into all sorts of humiliating situations throughout Skyhold.