Unfortun8ly the one site that could explain what's going on isn't credi8le due to 8eing run 8y a child a8user, 8ut I do have my own we8site discussing my own transition!
In addition, Alterhuman wiki has an article on a very similar phenomenon. There's also the Freedom of Form Foundation, whom I'm working with.
I think I can give that. As another autistic folken I completely understand this.
Transcharacter: a deviant trans identity pulled originally from the transID community, in which the folken/person affected 8elieves they are or are supposed to 8e a fictional character. Individuals with this identity may or may not seek to transition to their real selves, and may experience mild to extremely severe dysphoria surrounding aspects of their body, mentality, and place in reality.
As for the context and the 'why,' it's kind of hard to give those, right? No8ody really asks why you're trans, you just kind of are. 8ut I will say I've felt nonhuman since early childhood, wanted my left eye gone for at least as long, and have always craved a rigid social structure. I remem8er 8egging to have my hair dyed 8lack for eight years (yeah no that's not a quirk joke that's 100% /srs. Started when I was eight, got what I wanted at 16.) Then I saw fanart of Vriska on Tum8lr and kinda went "yeah wtf that's me. Why is that not me?" Read through my source twice and the dysphoria I'd always experienced came to a head and I decided I'd 8etter start transitioning 8efore it drives me mad. Not a clue why I had Feelings over such specific tr8s 8efore ever 8eing exposed to Homestuck, could 8e something supernatural for all I know.
Anyway here's my we8site if you want to read transition goals and such