Help, this guy is full of it..?

Well.. this guy i kind of liked asked me out.. and at the time i was chatting to a mutual friend of ours.. and our mutual friend said i can do better than this other guy and all.. and well the guy who asked me out has turned very cocky.. which is a turn-off for me.. but he seems to think i'm going to be here whenever he wants me.. how do i bring him back to reality?