Lil,
Only going on what you have posted, but it sounds as if he KNOWS he has he upper hand, and likes the power behind knowing this. I may be wayyyy off, but it also sounds as if he uses this as a way of working off his own frustrations...he may not be King somewhere in his life (his work situation maybe?) but he is when he dominates the scuffles? Just a guess. Me thinks if any of the above is true (and what the heck do I know?), then calmy, very calmy, sitting down and having a heart-to-heart is in order here. When does it become too rough? When the other person is uncomfortable with it, or in danger of it going too far. Then...when and IF it does, it is a whole new ballgame and becomes abuse. Take care, and I hope I haven't said too much. Trying ONLY to help. Honest