Have you heard the word of the Lord? It is possible to be a literal cartoon character. Praise be.
Fictionkin are people who think they are a fictional character. There are a million different ways they explain it, like multiverse theory, reincarnation, astral planes, anything their little hearts can come up with. I almost envy that kind of blind passion.
You would not believe the number of kids who think they're FNAF animatronics or Steven Universe gems. Sometimes multiples at once. They call them "systems" in a giant pretend game of Dissociative Identity Disorder.