Kyon from The Melancholy of Haruhi Suzumiya. (without him the world would be kaput already!)
Yuu Nikaidou from Shugo Chara (he doesn't stay bad forever thou)
Medusa from Soul Eater
-----Now who are yours!!!
Caught up in One Piece!! ʕ•ᴥ•ʔ *confetti*