Rokurou, a compassionate second-year middle school student with an impressive knowledge of the ocean, resides in Hoshimi town, a narrow strip of land nestled between the mountains and sea that lacks even the most basic amenities such as convenience stores, gaming centers, or family restaurants. During an encounter on the shore, Rokurou meets Seto, daughter of the former totalitarian leader of Murakami Mining Company. Seto, naive to the ways of the world and without the skillset necessary to support herself, was living independently before Rokurou intervened. The two team up to hunt sea creatures while Rokurou takes on the role of Seto's caregiver.
