At Zasshono Academy, new student Mifune Densuke arrives expecting a quiet start to high school life. Instead, he stumbles upon the enigmatic Eiken Club, where a circle of confident and curvaceous young women, including top-scoring Shinonome Chiharu, conduct their mysterious activities. When Densuke is unexpectedly drafted into the group, he finds himself swept into an unfamiliar world of spirited personalities and unexpected challenges. His once ordinary days quickly fill with budding connections and chaotic encounters that upend his routine.