If the reason because of his conscience eating him. A conscience where he give himself to that old lady, then I couldn't help but hate him.
Wasn't it to prevent other people like his mom and that old lady take advantage of Namaeun or to stop Namaeun from worring too much? It's just my thoughts, but I think he's got some kind of complex that makes him think he is similar to his trashy dad whenever Namaeun is there to support him, like with the tuition fee. I guess it just ate away at his conscience whenever it felt like he was just using Namaeun?
If he really did like or love her.
He shouldn't broke up with her but rather confront her to tell everything.
Spill everything.
Communicate is really a must for couples.
Yeahhh, that's the best course of action no matter what kind of relationship it is. I just like to think that he doesn't because there was no one there to demonstrate it to him that communication can go a long way for anyone and everyone involved. Both his parents have a terrible relationship with each other so he won't see that there and Namaeun, herself, said that she has a similar way of loving a person as Yujun and also, Namaeun had a not so okay familial situation growing up. Both didn't have anyone to show that communicating is an amazing thing.
I'm curious what's the reason behind their breakup. (Yujun and Namaeun)