Guys what can a girl do that makes her irresistable? Gals: What have you done that a guy couldn't say no to?

Hey every one. I've been seeing this guy for a few months now but for the last two months he's been trying to just be friends with me because his best friend doesn't like me and says if he doesn't stop dating me then she's gonna stop being his friend. I think it's ridiculous but i do understand that he doesn;t want to lose her, they've been friends for a long time. Thing is, I've been seducing him every time we're in town, his best friend can't go clubbing because the lights give her migraines. And most times it's worked. I don't really wanna force him into a proper relationship, I'm fine officially being his friend and unofficially dating him and i'm only persisting because the intimate moments are really great. My question is what can I do to make him keep saying yes? Guys, what moves/words etc has a girl done or said that you really liked, especially if you were trying to refrain from doing anything to her? And girls, what do you do that guys really like? If he really isn't in the mood I don't push it, but generally he lets me. He just feels guilty going behind his friends back.