Someone who gets a hard on when they see a sexy man or woman. Someone who would have sexual relations with a man or a woman. But would only date or marry someone of the opposite sex.
Someone who's ultimate fantasy is to suck cock while they have sex.
Adam: Dam that girl has some nice boobs! I wanna suck on them!
Rob: Yeah man she is hot!
Adam: Dam look at that guys tight ass! I wanna go down on him!
Rob: Gross dude... Don't you have a girlfriend?
Adam: Yeah bro I'm a bedroom bisexual