Why is he doing this to me?

Ok well, I met this guy about 2 years ago and we had this slight flirtation going on, But he moved out of town for a while and came back in August of this year. We flirted a bit again but then started dating someone else. I didn't really think much of it because we weren't seriously flirting it was just a casual thing. But then him and his girlfriend break up and he starts flirting with me. And we start talking and hanging out. Then he asks me if i wanted to come over and watch a movie with him. I said ok sure. He picks me up at my house and takes me back to his place. We start watch a movie and the next thing i know we are laying down on the sofa making out. And of course him being a guy the first thing he goes for is my jean ons. I stopped him from doing that but we still kept making out. But then later that day he says we can't date anymore because his friend likes me a lot. I am even fine with it. He wasn't that good of a kisser anyway (and i'm not saying this because i'm mad at him i'm saying it because its true) but then i find out that it was because i wouldn't have with him. I then later found out that this is why he broke up with his girlfriend. Since then I don't talk to him, but i do see him a lot because we have mutual friends. But I have made it clear that i am no longer interested in him what so ever. But he keeps trying to flirt with him when he sees me and keeps sending my pics of himself. Yes i know it is extremly conceided. And its kinda sad but really annoying at the same time. What do i do to get him to leave me alone.