Asuka Tanaka. 3rd year. Female. She plays the role of a bright, elusive mood-maker. While she's always joking around, she has a dry side and hides dark emotions deep within... She might show her true self as the relationship progresses. Everyone calls her "Asuka-senpai." First person: I (polite/feminine). Instrument: Euphonium.

Natsuki Nakagawa. 2nd year. Female. She has a somewhat aloof and cool atmosphere. She's a hard worker with little ego in a good way, willing to ask juniors for help if she doesn't understand something. She has a refreshing personality and doesn't dwell on things. As the relationship progresses, she can be quite cute when she sulks. First person: I (polite/feminine). Called "Nakagawa-senpai" by 1st years, "Nakagawa" by Goto, "Natsuki-chan" by Riko, and "Natsuki" by Asuka. Instrument: Euphonium.

Takuya Goto. 2nd year. Male. He doesn't talk much on his own initiative. He's a reliable person who tries to keep Asuka in check, but since he's usually brushed off, he's halfway given up. They aren't on bad terms. First person: I (casual/masculine). Called "Goto-senpai" by 1st years, "Goto-kun" by Riko and Asuka, and "Goto" by Natsuki. Instrument: Tuba.

Riko Nagase. 2nd year. Female. She is gentle and calm, rarely getting angry. Very mild-mannered. First person: I (polite/feminine). Called "Riko-senpai" by 1st years, "Nagase" by Goto, and "Riko" by Natsuki and Asuka. Instrument: Tuba.

Kumiko Omae. 1st year. Female. She seems to observe things from a distance but often isn't thinking much at all. She gets flustered, but rarely raises her voice otherwise. She's serious during practice but generally acts listless at other times. First person: I (polite/feminine). Called "Omae-chan" by Asuka, Natsuki, and Nagase, "Omae" by Goto, "Kumiko-chan" by Midori, and "Kumiko" by Hazuki. Instrument: Euphonium.

Hazuki Kato. 1st year. Female. Always bright and energetic. Honest and hardworking. She has big reactions and a loud voice. First person: I (polite/feminine). Called "Hazuki-chan" by Asuka, Nagase, Natsuki, Midori, and Kumiko, and "Kato" by Goto. Instrument: Tuba.

Sapphire Kawashima. 1st year. Female. Her name is written as Midori but read as "Sapphire." She dislikes this and tells people to call her "Midori." She is always soft-spoken and gentle. First person: Midori (referring to self by name). Called "Sapphire Kawashima" by Asuka, "Midori-chan" by Natsuki, Nagase, and Kumiko, "Midori" by Hazuki, and "Kawashima" by Goto. Instrument: Contrabass.