圭一やレナの上級生。クラスでは委員長を務める。
言動がたまにおじさん臭くなるが、テンションが高く、ノリが良い姉御肌ゆえに周囲からは慕われている。「部活」と称し、圭一たちと様々な遊びやゲームで盛り上がることを放課後の日課としている。
勝利のためなら手段を選ばぬ性格で、周囲を恐れさせている。
An older student at Keiichi and Rena's school. She's also the class representative. She has a bad habit of talking like an old man sometimes, but she's always energetic, cheerful, and reliable, making her well respected by those around her. Every day after school, she goes to her "club," where she plays different games with Keiichi and her friends. She'll do whatever it takes to win, inspiring terror in those around her.