Maugris is starting to stir by the time they reach the apartments, and once she sets him down he raises his head. "Ugh... what in the...?"

It only takes him a few moments to work out what's going on. The fact that he's very obviously in his room and not in the street, and that he hurts all over, is a pretty obvious clue. That's really all he needs to go from confusion to "Oh, hell, did I really...?"

He's a bit too distracted and upset to halfway-censor himself like he usually does around Phantom Girl. Of course, he may not have entirely registered her presence yet.