Rokurou, a junior high school student living in a seaside town with no entertainment, meets Seto, a former noble daughter who is now self-sufficient and living alone for some reason. Rokurou, who knows the seashore a little better than his classmates, becomes an advisor (?) to Seto's survival lifestyle, and together they spend their days immersed in the sea in search of prey. There are no convenience stores, arcades, or diners, but let's have fun together in this town!