[Huh. So is she familiar with that kind of thing from back home? Or, if she's like Takeru and that other kid, some other strange world-hopping adventure? His curiosity remains, but he reluctantly files it under "probably not my business" for now. He shrugs.]

It was just somebody from home. You don't have to tell me anything.

[That's also her business. If they both saw something, he has to think that the "what" of the illusion doesn't matter as much as the "how" or "why." Which also doubles as a convenient excuse to not think too hard on it in favor of zooming to a safer topic.

With enough sarcasm that you could choke on it, he adds:]

Welcome to the team, by the way. [And more genuinely:] I've been here for a while, so go ahead and ask if there's something you wanna know.

[To return the favor for her door explanation, as it were. He'd feel better having the debt repaid in his mental ledger.]