An ugly, two-faced, double-crossing whore. Will seem nice at first, and then she will turn into a total bitch, and you will ask yourself "Why is she my friend?".
Beware of Hannahs, they make terrible, needy girlfriends, and you'll never have good sex.
Chick 1: What the hell is up with that chick?
Chick 2: Oh, she's a Hannah