Miri Natayama

Natayama often wears a bland expression, but is prone to violent fits of emotion - usually anger. Because of her talent with shogi, she is harsh on less talented players, and is used to standing over people. She is very prideful of her abilities, and quit the Shogi Club when she felt she had not been recognized, despite endangering her scholarship by doing so. Natayama claims she does not blame the weak, but blames those who do not try to get stronger. She does have something of an immature streak, taking a petty revenge on the Shogi Club. After the Student Council's intervention however, Natayama's social skills are improving, and she has started to get along better with club captain Sasae Mochibaru. She only appears in the anime adaptation.

(Source: Medaka Box Wikia)