Asking was definitely worth it. Despite her prior confusion and distress, a little smile formed on her face as she watched the little spheres and then the cube.

When he turned invisible, her eyebrows raised in surprise.

"Oh, that's interesting. Thank you. The part where you turned invisible is a bit like something that people can do with genjutsu in my home." It occurred to her a moment later that she should elaborate. "Genjutsu is different kinds of illusions and things that affect the mind."