It's when he's doing the third handstand, shifting his weight back and forth so she can compare the biological to the vibranium, that Shuri finally thinks to ask, "Why did you come by, anyway?"

Bucky peers up at her from his upside-down position. "Partly to say hi, partly to see about checking in with Steve, and --" Might as well ask, he decides. "--partly to see what you think of Halloween? As a thing for the kids here, if you think they'd like it?"

The enthusiastic shriek the princess lets out threatens to deafen him, and he starts laughing.