I don't think he knows, though he does obsess over Qi An a lot for some one he hates/ despise.
Yes he knows
I don't think he hates him..I think that he is angry because he left without saying anything..I guess...
I think similar, I believe he loves him.
He gets him to eat, gives him a promotion, Takes care of him when hes passes out (at the bus stop). It wouldn't surprise me if he makes Qi An go out and buy clothes!
I'm a bit lost..So does You Du knows that Yi You and Qi An are the same person..? I already read it twice but still can't tell....