[Hmm, so it really was the convenience store she was asking about. Interesting-- she seems a lot more familiar with what he's saying than vice-versa.]

Well, in my experience, something like this happens when a powerful ayaka-- er, spirit has enough influence that their realm overlaps with the human world. Sealing or otherwise dealing with the spirit should end it.

In any case, a convenience store is where you can go at any hour of the day to buy just about anything you need. See? Convenient.