Miu Nomura is the fourteen-year-old protagonist of the anime. She has been playing the piano since early childhood, and as a young girl the music she made brought her great joy and a desire to share that feeling with others. As she enters her teenage years, however, she becomes an introverted and reserved person: shy, soft-spoken, and far too timid to express her emotions openly. This inwardness eventually affects her piano playing, which loses the passion and ease it once had. Her piano teacher, Shirakawa, notices the decline and grows impatient because he knows she is capable of more if she only tries harder. Miu is diligent and hard-working, and she acts mature and responsible for her age, but her heart is no longer fully invested in her lessons.

Her emotional life is further complicated by a strong crush on an upperclassman named Kazuya Takahashi. She is too shy to confess her feelings, and the unspoken attraction both distracts and unsettles her. At the same time, her best friend Yuuki Matsubara also nurses a secret crush on a third-year track star, so the two girls share a parallel romantic uncertainty. Despite the turmoil, Miu’s feelings for Takahashi unexpectedly begin to spark her dormant musical passion. Under Shirakawa’s guidance, she decides to compose her own piano piece and perform it at the spring recital, hoping to rediscover the joy she once knew. Her relationships with her family, friends, and the object of her crush all shape her gradual growth, as she learns to let her emotions flow through the music again. Miu’s notable ability is her talent as a pianist, but her real skill lies in learning to channel her personal feelings into her compositions, a process that becomes the heart of her development.