It doesn't go to a lock like the ones on our rooms or whatever, but it's a similar sort of, like . . . technology, I guess? [She hands the key back to Sayaka, because honestly if she finds this lock she'll probably just pick it.] If you found it in the bottles or whatever, I'd say it probably goes to, like, a safe or something rather than a room?

That's, like, just my opinion though.