"I will need to stay here, though. I'll need to protect my notes. I have created the most comprehensive guide to Hogwarts since the original blueprints were drawn up! I can't very well let anyone come in and ruin that. Oh, but I'll need to slip out for supplies sooner or later. Those traps you set off will need to be reset and why do I think you've managed to bumble your way into breaking more than a few of them."

"Yes, well," said the Hat, not particularly repentant. "Had to get in here didn't I? And, again, I'm not on the Housing Committee, but I don't think they'll have an issue with it. The mandibles, I mean. I suppose having lived without walls in a (kind of weird) mind for so long can leave you longing for your own home, with walls and things. Do you know how long I've been in this castle? I certainly don't, but it feels like several thousands of years; if the mandibles would release me, I would spend a year or so travelling. Anyway, its not really my time to do that yet!"

"Well, I couldn't very well take one of the dungeon rooms as a home. I'm far too used to observation to be that close to the thick of the action anymore. And, well, the other tower was no good for more than the obvious reasons. No, Gryffindor wouldn't do at all."

"It rather wouldn't," said the Hat, considering this as well. "I believe it would not entirely meet your requirements of walls and roofs and functioning toilets. Not that this is an insurmountable obstacle; as many as one billion people still have to use the great outdoors for nature calling, and let me tell you, for Muggles, that kind of thing can be very messy. They have more of those mobile phone thingies in the Muggle world than toilets, seems quite illogical doesn't it? Back in the good old days, they worshipped Cloacina, the goddess who presided over the Cloaca Maxima, the "Great Drain"; not sure what they're worshipping these days, those crazy Muggles."