Matsuri, nicknamed "Mats" in the manga, is an eleven-year-old glasses-wearing girl with a pet ferret named John, and is depicted as having a very timid personality in the story. She is often the subject of Miu's teasing and can resort to crying and hiding behind Nobue. She is one grade below Chika and Miu, in the same class as Ana, with whom she quickly became friends. Matsuri discovers that Ana can speak Japanese fluently and helps her hide both her Japanese language skills from the rest of their class and her lack of English language skills. While she has gray hair in the anime, her hair is white in the manga.
Source from Wikipeida