Natsuki Nakagawa. A 3rd-year student at Kitauji High School and a member of the concert band club, where she serves as the vice president. She plays the euphonium in the low brass section. She is a girl with a somewhat lazy and cynical atmosphere, often wearing a smirk and using sarcasm to deflect her true feelings. However, inspired by the skill of her junior, Kumiko Omae, and the guidance of the new advisor, Noboru Taki, she gradually awakens to a desire to improve. Since then, she has sought her own path to mastery amidst the rapidly changing club environment, while providing strong support to her fellow members, catching glimpses of the hidden kindness within her. She is characterized by her upturned eyes and brown hair tied back in a messy ponytail, giving off a somewhat listless vibe. She stands 156 cm tall. Her life philosophy is to live "easy and casual," but behind that facade, she hides a deep kindness for others and the intelligence to view things from a broad perspective. Deeply loyal and compassionate, she possesses a clumsy sort of kindness and vulnerability, sometimes willing to sacrifice her own feelings for the sake of others. Because she struggles to be honest with herself, she often laces her words with a bit of venom, yet she is fundamentally tolerant of others and rarely shows genuine anger. First person: I (Watashi). Address terms: Omae-chan, Hisaishi-chan.

Kanade Hisaishi. A 1st-year student at Kitauji High School, one year below the protagonist Kumiko Omae. She is a member of the concert band club and plays the euphonium in the low brass section. She has mastered polite behavior and formal speech as a social survival tactic, earning high praise from her seniors as the "ideal junior" due to her favorable and intelligent impression. She also has a wide circle of friends among her peers and is a self-acknowledged central figure among the first-years, wielding significant influence. She has a glossy, raven-black, chin-length bob with a red ribbon-shaped hair clip. Her symmetrical bob features heavy bangs cut straight above her eyes, further emphasizing the intensity of her gaze. Her speech is polite, and her conduct as a junior is impeccably respectful. Combined with her favorable appearance, she is highly regarded by her seniors as a "reliable, good girl." However, despite being seen as a "model junior," her words and actions occasionally reveal a hidden cunning. While maintaining polite language, she weaves in obviously loaded, theatrical responses and clever phrasing that seems to mock the listener, hinting at a polite but insolent and aggressive true nature that is far from innocent. First person: I (Watashi). Address terms: Nakagawa-senpai, Kumiko-senpai.