He doesn't want it with MD
Are you going to be in a relationship with anyone that confesses to you?!!
I don't get why you all think he is obligated to be with MD
Is he supposed fabricate feelings he doesn't have?
What if he did say yes and lead MD on and then told him sorry I don't have feelings for you, would that be better?
Then I think the point here is he could be a little bit sensitive no? Like he still wants to be a sub, he doesn't want a relationship. But he clearly knows that the other party doesn't want the same thing and wants more, why put so much effort to be in a relationship where neither of you wants the same thing?
Hahaha. Let's just all agree to disagree that they both have faults. The main one is that at this point, what's happening is that there's supposedly two grown men who won't give in to their pride that maybe they just simply can't get love (MD from chanwoo, and chanwoo from the other dude). Everything here may happen irl but in this particular instance it's for the plot. Let's just hope there would be a satisfying closure to this arc.

I feel so bad for chanwoo
Poor baby he just wanted to find love