is it just me or does MD saying the safe word was damn emotional

Oh 100% that hurt

I thought it was a good choice on the author part. showing md realizing, that throwing his anger on chanwoo, made him no better than chan woo ex.
also that fact that he choose to end it for the night shows that even though he didn't suffer physical damage he's capable of an emotional one, although his rough demeanor and roll as the dominate one in their relationship