His relationship is part of why he isn't fazed by fangirls. Of all the female attention, he's said, "To what end? I have a girlfriend. If you were, like, 25 and a p*ssy hound, being famous would be awesome. But it's not like I'm spending too much time in Vegas or in the Hollywood clubs or anything like that. So it doesn't really benefit me much."
Charlie has quite the dedicated followers, and in one of his more out-there fan moments, a woman wrote him a letter asking for a lock of his hair or . . . a toenail. Well, then.