You sound like a bit of a player. Sometimes a player settles down, but I think it is rare. Plus you are very young, and the likelihood of a lasting relationship at your age is small. I think it would jeopardize your friendship if you played this man's daughter. Only you know what your intentions are. Do you want a piece of ass, or are you serious about this girl? Are you boyfriend material or are you still too immature to deal with it at 20? You have to look deep inside on this one.