Does this guy like me?Please tell me..............?

Well sounds like he's definitely interested, but if he's this ladies man that you say he is and likes cheating then he may be looking at you as the (unobtainable one). The one female that he can't have and that intrigues him even more. If you aren't interested then keep it that way. Don't ask him why he stares at you because I'm pretty sure he's going to come up with something pretty smooth to say. Just let him stare because if he really likes you he should have the guts to tell you.