Seventeen-year-old Yoichi Karasuma, a master swordsman, leaves his secluded mountain home to enhance his combat skills. However, instead of martial arts, he finds himself immersed in the bewildering world of modern amenities and social etiquette. At a new dojo, Yoichi grapples with survival as he encounters the unpredictable Ikaruga sisters, challenging his understanding of girls' norms. Amidst the chaos, will Yoichi's swordsmanship falter against the allure of Ibuki, Ayame, Chihaya, and Kagome? Or will the formidable girls from the rival Tsubame school spell his downfall?