deidra:
his behavior says he likes her very much. I think she is his role-model. but he doesn't love her. in that matter, it's more important for him to make jiho mad than to earn points in seun's affection. everything he says and does targets jiho.
so my conclusion is, he doesn't love seun. maybe he is not aware of that, and genuinely thinks he loves her, but honestly, I doubt that. he is very much more aware of himself than jiho. he probably thought he loved her as long as he didn't see her, but since he met her in the flesh, I think he knows that he just admire her a lot.
I think I agree with you here. I think I'm seeing the character in a better light, because to think of it, Hae Jin could only be infatuated with Sang Eun. Hae Jin does not love SAng Eun, but rather he sees her as a role model.
Look at how messed up Hae Jin is because of his family. Remember how he described Sang Eun when his family came over his apartment? He said something along the lines of "she someone I can't be", indicating she adores Sang Eun for having the strength to separate from her family and live a life (having a different name) than being an heir. Hae Jin hated to be an heir more than anything, so seeing Jamie as Sang Eun made gave him some kind of obsession to be able to live like Sang Eun.