he's has feelings

Ok so I need so help. Me and this guy have been friends for some time and we just started have sex last month I told him I just wanted to be friends. He keeps telling me he has feelings for me and tells me he really likes me and over and over agin I tell him j just want to be friends but we can have sex and at first he was fine with it but I'm getting a feeling that he's getting attached and I don't have feeling in that way at all. So my question is should I stop having sex with him or what should I do??