Sapphire Kawashima

She is a first-year student in the same class as Kumiko and Hazuki. Her instrument is the contrabass. She has a positive personality. She is not fond of her name and calls herself "Midori," which is how Kumiko and Hazuki also refer to her. She was responsible for the contrabass in the wind ensemble of the prestigious "Seijo Junior High School." In Kumiko's third year, she becomes the leader of the bass section.