beta
At first. But the way the author wrote his character, he is beginning to grow on me.
I see him as a person wallowing in self misery because he knew he contributed to the suffering of his brother. He's trying to right his wrongs but life treats him like shit and he's trying cope and numb himself with booze, drugs, and sex. And in some way, it's like his form of self punishment too and just like that he cycles over and over to his bad habits.
Seeing the new development in the story, I don't think he even likes sex despite acting like he's always enjoying it. I really hope Jin treats him with care because Jian is in such a fragile state. I feel like one more shitty life event and he'll try to off himself.