sounds gay reading the description... oh wait it is wellp, with angel in its name i thought it be something with a woman but guys can be angels as well, kinda forgot about that teeny tiny part.
Interestingly, succubi don't necessarily have to be female. Etymology-wise succubus comes from the latin succubare which means "to lie under". It's just that succubi are female in fokelore because traditionally women tend to uhhh take during sex.
So after we got that out of the way, let me react properly to the game.
So it basically just means that he's the bottom.