Guwon didn’t kill his dad. He said it himself, also in the first chapter it’s shown that there was a robber— that’s the person who probably killed his dad. Also, teach still lays in bed with him b/c of the pressure put on him from that girl and the doctor, and all the Teacher wants to do is be helpful so he’s going to risk his life or use his body to do that. That’s why they still fucking, he’s doing it as a manipulation tactic. In previous chapters it’s shown he didn’t want to but then has a flashback to when the girl and doc said something of him needing to stick close to Guwon.

So, this dude is just gonna continue fucking his father‘s killer and falling in love with him?