I agree with most of what you said but he did try getting a blowjob from a random guy in chapter 28 lol ...he ended up feeling sick after that but still. But from now on I really think he can only bring himself to be with Nanjo... And he's experiencing doing it with someone he loves after a confession where he bared pretty much his every thought, I'd think feeling vulnerable is to be expected. I guess people forget but Mok is actually an introvert who doesn't even talk much, it's just with Nanjo that he ends up spilling everything.
And yesss I want to see jealous Nanjo so much... maybe they try to keep it casual for now until Nanjo gets jealous and that forces him to confront his feelings for Mok
Someone said Monk is out of character crying and acting like a virgin...Don't forget he hasn't been with anyone for the longest time. He has only been with Nanjo for quite some time now before the fall out. So he's holding back so bursting it as easy like that is understandable. Also, that simply means he has really fallen... he's not anymore that old monk who never cares what the other guy wants or feels during sex. Plus the fact he just came from the hospital and treading the waters with Nanjo again. You know that feeling when you're scared to disappoint someone again?
I bet we'll see Monk really losing the upperhand in the next chapters, while Nanjo will slowly rise as a power bottom.
I predict Monk would soon need a friend to confide with... Enters his babe (that other black-haired guy?)
That will soon be a wake upcall to Nanjo... Oh I bet we will see a jealous Nanjo soon. And I can't wait!!!