Fanfiction

You may be looking for fan fiction in the real world.

Fanfiction, or fanfic, was a form of literature where one wrote new works featuring preestablished, usually copyrighted fictional characters. Fanfic sometimes involved the writer writing a version of themself into the story.

Auteur claimed to have written a lot of fanfiction when she was a teenager. She later compared Graelyn Scythes's dream journals relating adventures she had with Archimedes Von Ahnerabe to fanfic, intending to throw her off the scent of the truth: that the dreams were real memories from before Auteur had turned Archimedes into a fictional character using the gauntlet. (PROSE: White Canvas)