I don't read the novel so I don't know much, but from what I've seen so far, Lyle's action are just ugly. He is forceful,coercive, inconsiderate, selfish, and always assume the worst of Jin. If I go blind into this manhwa without looking at the tags , I would assume this is some sort of psychological thriller. So yeah, as a manhwa only reader, it's hard to imagine how they will go from this to romance.
He eventually learns about the abuse Jin suffered at the hands of his servants, and he feels guilty enough to regret his actions and try to make things right. But the fact remains that he only learns the truth because of the accidental marking. If that hadn’t happened, I doubt he would have ever looked into jin situation, and Jin would have been left to die alone (︶︿︶)=凸

I’ve finished the novel, but I still can’t bring myself to forgive the ML. I know he had his reasons and that he suffered too, but that doesn’t erase what happened.
Maybe I’m not a forgiving person, but what Jin experienced in that mansion goes beyond being merely “terrible.” The trauma and pain he endured were unimaginable.
If I were Jin, I don’t think I could ever forgive Lyle. He robbed Jin of the chance to see his parents one last time. They were Jin’s whole world. No matter the circumstances, I don’t think I could forgive someone who made me lose my final chance to say goodbye to the people I loved most.