Senpai...? Minato blinks at that title as applied to his sister, but he figures maybe it'll get explained in the course of the conversation.

He waits a beat or two before speaking up after Yu looks him over. "Good morning... I'm her twin brother, Minato." He assumes surnames are already know between them; he also can't recall getting Yu's name, though the guy does look a bit familiar.

And he has this strange phantom memory of very hip swim trunks.