He always has feeling and care for her from the start, but it sad that she always hate him just because her parents adopted him, raise him, and favorable to him more than her. Its sad that she always insults him with words. I'm surprised that he still patient about it even insulting him with words can be hurtful . That's how the games of love started to pretend to like him and using him as a tool. I don't know how long he will put up with her.
Maybe later episodes she might do something that can go over board with her game plan that he's starting to become a cold person. I think at the hospital she might really has have feeling for him and the baby but doesn't want to admit it. That's why it hit to flashback where it all started. I'm not sure if it going to be added this storyline to scene on the later ep, but I heard form the novel version that she didn't want the baby from him and wanted to get abortion. He want to make a deal with her to keep the baby. She can leave him forever and he can raise the baby by himself.