It's not weird, that is only to be expected. So far, you've only seen mostly the bad side of him. So it's hard to imagine he has a tender side that allows him to love & cherish someone. Since the development is slow, this will be ongoing for a while. In fact, you may come to hate him even more in the next few chapters. But then again, given his circumstances, his attitude makes sense. If you have read The Secret Garden by Frances Hodgson Burnett, you'd probably see the similarity between Jeong Ha and Mary/Colin in that story. Both Mary & Colin were born in very rich family, but they suffered ill health (Colin in particular), and behaved like spoiled brats in the beginning. Jeong Ha is just like that. Suffering & unhappiness make people like that. You can probably even recognize & name examples in real life if you look closely enough. It's understandable to hate this behavior, but it's just as important to understand the circumstances that make someone behave in this way.
As we go further and further I hate Jeongha more and more not less as some have said I would. Weird.