>>2951426It's a mix of twitter trannies being trannoids and fujos finding out that they can self-insert better by giving the bottom a pussy (the closest thing they'll ever be to actual penis in vagina sex). They live in their twitter echo chambers and once one starts doing it, the others join in.
I'm also sure ABO has something to do with it, but it's true that it's especially prevalent in Genshin fanworks for some reason.
