25 (m4a) UK not sure if I want to become a sissy or fuck a sissy, can you help me decide?

I'm really into being dominated by girls, my girlfriend fucks my ass a lot and makes me eat her creampies. Recently I've been jerking to sissy and trans porn but I don't know if it's because I wan my gf to make me become a sissy or if it's because I want to fuck one