his posture as Kunlun is quite different from his contemporary Dragon City posture, isn't it? There's no slouching or hip-cocking, and no pockets for him to stick his hands into.

I think part of it is simply the costuming, but I wonder if it's also that he feels he has a different type of responsibility as Kunlun. Like he knows how important Kunlun is to history, and he feels the need to live up to that?