Yujae(YJ) is kinda "stuck in the past", he wants to go back to being just friends with Hanjun(HJ) even after HJ confessed his feelings so I feel like he's disregarding how HJ feels after effectively being rejected. HJ wants to move on from this, like try to bury his feelings but YJ is also leading HJ on since YJ himself is confused about his feelings.
I personally dislike YJ because HJ is trying his best to change himself since most of his world was(and lowk still is) centered around YJ but he got rejected. He needs an escape from the hurt of rejection. Imo HJ has set boundaries with YJ but YJ keeps crossing the line and each time they get hurt, they just bury their feelings and act friendly again. The fights they've been having are like little drops falling down the side of a full water cup, maybe this will be the overflow point.