Xichen does not smile back, but his expression as he watches her - and plays - is soft. This much joy, it is precious, and it deserves protecting, rather than dragging down.

When the melody winds down, he lowers the flute and then cups his hands at her. "Welcome to the Voidtreck Express." The train is large, but not nearly large enough for Xichen to not have at least glimpsed most people here. It's still a guess.