This is a little obscure, but I would have sex with the demonically possessed dick girl from the hentai anime, Bible Black. Not only is she an attractive character, but she has both a large penis and a vagina. Seriously, how awesome is that?
Take a look at my avatar. That handsome fellow smoking the cigarette is Ryuichi Asami from the yaoi manga series, Viewfinder. He is seriously hot stuff. Too bad he plays for the other team!