Haruo Hibiki, a dismissed former up-and-coming conductor of the Cosmopolitan Philharmonic Orchestra due to his disagreeable temperament and inability to collaborate, struggles to find another conducting post. He accepts a teaching position at Kawagoe Private Academy, directed by his grandmother. She issues an ultimatum: win the National Boys Choir Competition with a school choir he must assemble, securing his return to the orchestral world. This goal drives Haruo to recruit students aggressively, often exhibiting eccentric and socially inappropriate behavior like intrusive physical assessments and boundary violations. He initially targets former choir member Tenshi Dei, who suffers severe stage fright, and Tenshi's friends Hiroshi Yazawa and Shuji Shiratori. Possessing traits of an ISFP and Enneagram Type 6w5—artistic sensitivity, strong personal values, loyalty to objectives, skepticism, and intellectual curiosity—Haruo expresses frustration physically, declaring he "speaks through his fists." His teaching lacks empathy or structure; he demands immediate results without guidance, causing conflicts. He forces recruits into complex dance routines before vocal fundamentals and uses unconventional methods like spraying water to correct pitch. Interactions with the choir members, particularly efforts to help Tenshi overcome anxiety, gradually shift his focus from self-interest to genuine investment in the boys' growth. Despite his abrasive exterior, he demonstrates perceptiveness in vocal techniques and performance potential, using professional expertise to cultivate raw talent. His development involves learning to channel his musical passion into mentorship, though his methods remain unorthodox and communication blunt. His arc culminates with the choir competing nationally, his personal redemption tied to their success and his evolving relationship with the students.