So far whatever was making the noises seemed to have heard her looking for it, because it had gone silent and she wasn't finding it. But looking was more interesting than sweeping, so keep looking she did. Until said looking was interrupted by the arrival of the girl she hadn't signed up to babysit, that was.

And accusing her of being a Gryffindor.....? Really? "Slytherin, actually. And nothing stupid about looking for something that's making a noise. It's probably just a mouse, anyway." As for the adult thing, well, she was almost one of those herself, technically. In the Wizarding world, anyway. Besides, dude would probably tell them to deal with it anyway. "Just saving time," she said, finishing her thought outloud.

And it seemed that the brat's questioning had caught Cassia's attention as well. "Not yet." But she was still keeping an eye out for it.......