Maybe he knows that you like him and he's trying to use that so he will have someone to hang out with at parties or wherever so that he'll have someone there that likes him..... Some guys know that if a woman sees another woman attracted to a man, it actually boosts his attractiveness in her eyes and she will want to know more about him. I sure hope that's not what he's trying to do, but I can't think of any other reason why he is trying so hard to get you to go out with him if he has no feelings for you.