Nina Einstein from Code Geass - she's a crazy lesbian
Beauty from Bo-bobo - She's the most useless character in the show (and she gets captured in sometimes)
Sae Kashiwagi from Peach Girl. I'm sorry but that girl is like Satan in seifuku. Also, any squeaky high pitched voices incur a sort of automatic distaste on my behalf.
Hinata in Naruto. Her personality just pisses me off. The overly shy and not confident, always hiding from afar watching the person she 'loves' making her look like some sort of stalker. Ino too. Her love for Sasuke, and when she hears that they're going to kill him or some sht then becomes all dramatic. That one episode just made me hate her. These types piss me off so much.