Responses
Hyunjae offers to become Yoojin's ***: Ch216
Fun arc begins: Ch220
Breakdown: Ch277-278
If you're interested in the breakdown, I know someone made an animatic of it on Youtube. It's called Chapter 277 || My S-Class Hunters. It is very spoiler-heavy though, so only watch if you've read the novel or don't mind spoilers.

Just so y'all know, Yoojin's breakdown is still a ways away. We still have a big (incredible) arc to get through yet. And some more intriguing ("subtle") talks with Hyunjae!