Suddenly, Natsuki receives a message from Hikarisaying she's nearby. Worried about Hikari, who says she ran away from home after an argument with her father, Natsuki reluctantly lets her into her house. Natsuki is nervous being alone in her room with the person she likes... Amidst this, Hikari confides in Natsuki about her relationship with her father, her past, and her dream of becoming a novelist. The next day, in order to gain her father's approval, she makes a certain decision.

September arrived, and with summer vacation over, everyday life returned. Natsuki is invited by Serika to form a band together. Confused by the sudden offer, Natsuki initially tries to refuse, but realizing Serika's enthusiasm and her own desire to live a youth without regrets, she decides to join the band. The two immediately begin searching for other band members... Meanwhile, Hikari has made up her mind to confront her feelings for Natsuki.