The main character of Kimi ni Todoke.
She has brown or black eyes and straight, long black hair (with blunt bangs).
In the book/anime, everybody around her fears her because of her unusual appearance and the fact that her name also sound very close to Yamamura Sadako from The Ring. People would even call her Sadako, either by accident or on purpose.
Her motto is "A good deed a day," but it's usually hard for her due to the fact everybody runs away screaming whenever they see her.