I think it's kinda normal giving his background and his father making him feel he was never good enough...i recognize that Kim Dan has done nothing wrong, but i really think that anyone would be frightened to be looked down on and on top of that... fighting against the little time you have left with the person you recently discovered that you loved (and recently realized that you were pretty shi*** to too). He must think that Kim Dan too is fed up with him...must be really frustrating i think, giving that he's little stupid and just recently began to practice not to take his anger on Kim Dan 