It's not a direct apology, but Baiyi does have a brief look of contriteness before it fades. He regrets that his years in the mountain have resulted in forgetting some degree of social etiquette. On the other hand, those tend to be tedious, trivial, and obnoxious so he doesn't completely regret leaving some of those practices behind.

"Is it due to your condition?" He asks, his gaze lowering down the smaller man's torso before returning to his face. "You don't have the same energy as a grown man's."