The story centers around five Japanese high school students who are too young to be called adults, but who no longer think of themselves as children. Wakana Sakai (Ayahi Takagaki) once took music lessons, but she withdrew from music after losing her mother. Konatsu Miyamoto (Asami Seto) is a positive-thinking girl who loves singing and spends time after school at the vocal music club.

Sawa Okita (Saori Hayami) is a spirited archery club member who dreams of becoming a horse rider. Taichi Tanaka (Nobunaga Shimazaki) is a chronically late badminton team member who lives with his college student sister. “Wiin” (Natsuki Hanae) just transferred into Wakana’s class after 12 years abroad in Australia. Music brings Wakana, Konatsu, Sawa and the others together into an ensemble during their last summer in high school