Yōji Sugawa shares a five-year relationship with Chiaki Aizawa. After he casually mentions accepting a job transfer requiring relocation, Chiaki voices dissatisfaction with long-distance arrangements and initiates a breakup. Yōji misinterprets this as a definitive end. Seeking closure, he invites her on a final trip to Nanto in Toyama Prefecture, where they first dated.

During their visit, Yōji's affection deepens. He notices when Chiaki wears makeup and compliments her, and buys her slippers to demonstrate thoughtfulness. Yet he repeatedly makes unilateral choices, like briefly abandoning her during a festival, highlighting their communication struggles.

At Nanto's Paper Lantern Festival, Chiaki confronts Yōji about his failure to invite her to relocate and his pattern of poor communication. She clarifies her breakup request stemmed from hurt feelings, not a true wish to separate. When she flees, Yōji pursues her. They reconcile near the old Toyama Agriculture School, reaffirming their commitment. This prompts Yōji to recognize the necessity for mutual decision-making and improved communication.