"What does that... So, you're not Zangetsu, you're just... in his body." That seems like what this - the man Gongenzaka, of all names - is saying, and Beau shifts to follow him if he continues jogging. "What, you switched bodies? That can happen?"

If that's something that can happen, even if only specific spells, she wants to know about it. Partly out of idle curiosity, having something else to occupy herself with, and partly... the better to make sure it doesn't happen to her.