
BDSM where dom is mixing his feelings and grudge with a play? Where he is taking his anger out on the sub because he had audacity to reject him? Where he makes sub participate in the play and things he is uncomfortable with under disguise of BDSM scene? And he knows sub won't refuse because of conditions he put on him and they are impacting his choices. What's more it was shown that Chanwoo has problems with limits, he didn't say anything while being strangled to death and MD is fully taking advantage of that. He isn't interested in the other sub in the slightest, he is just getting petty revange on Chanwoo.
This isn't good or safe representation of BDSM.

He is a sub. A sub supposed to obey orders. You either do it or you say the safe word and it is over. Sorry, that is how this game is played. Also MD and CH are not a couple (as per Ch's wishes) so no emotional attachment is involved. If it is just his pride, yeah ok that's the role of the Dom, to crash sub's pride

also, MD already gave him a chance to not join but he still did anyway bec he didn’t want to be replaced as a sub. i think MD would’ve done the same to the other guy if he was the one who disobeyed like that. that’s just how it works and who knows, BDSM might have something even worse than a slap (for those who don’t really have BDSM as their kink) hehe

Your reading comprehension is actually close to 0. He was angry before. Now I believe he is overjoyed. Because Ch managed to hit his head on a wall all by himself. He kept telling him that he had a lousy taste in choosing partners (a mega true statement). And now due to Chs stupidity they have gone back to Slave Training 001. And Ch actually paved the way. That is what is happening.

He was shocked by the slap and he didn't know he will have to make out with the dude. So no. Literally they didn't discuss shit.
And MD knows that Chanwoo doesn't enjoy that but he sti literallu coerced him into the play. But live in the bubble that this situation is normal, safe and perfect BDSM representation.
Are you all amnesiacs? If you do not know what BDSM or Dom/Sub is at least reread the chapters of MD/Chanwoo again. Remember when Chanwoo was like in the beginning, MD got mad and started behaving hardcore BDSM and Ch said at last, I loved it! I am reading some idiotic comments about toxic relationship and the facepalm is not strong enough to deal with this. They have a relationship based on sex. And not casual sex, specific, hardcore, kinky, agreed from both of them sex. MD asked to become lovers. CH said no. And after a few days he called him to meet his new boyfriend. So MD is simply does what they have agree upon. A kinky hardcore BDSM sex. Is CH going to realize that he loves him? Ok if that happens I hope that MD won't tell him "sorry, too late" (his and everyone's prerogative). He fully consents for what is happening. He (at least what he has told so far) have NO romantic feelings for MD, he just loves the sex. It is also MDs right to either change Sub or find one ton also be lovers with. So go hug your teddy bears kids.