It has depth in terms of emotion but Yang is the only fleshed out character here. Qing's condition doesn't manifest itself until it was explained. The use of color in the sounds he hear could've helped in showing his condition and could add to its beautiful art. It could even be made clear as to why he kept rejecting Yang when they first met.
He left without an explanation and came back all of a sudden, too. Like, why?
Xiao's role is a little confusing. It's like, I understand that he was going to an obstacle, telling Qing that Yang wasn't going to love him. But at the same time, the jump of his importance to Yang (to the point of being a reason for Yang to leave even when he likes Qing and Xiao or the bar didn't seem to be something Yang really desired to leave for.)
The mother is given a redemption filler even if it sounds pretentious and does not really justify anything from the past, rather just another reason to dislike her.
Anyway, the art and basic plot is admireable.
Silent Color