In modern-day Japan, only the direct descendants of samurai are allowed to carry swords. In Takahara Ibuki's neighbourhood, rumors have been spreading about Shiroyasha - a mysterious swordsman who is said to attack other swordsmen. Many skilled sword-fighters have converged in the city with the hope of hunting down Shiroyasha.

On his way home from school, Ibuki witnesses a fight involving his classmate, Haruma Kokonoe, who is the strongest swordsman in their kendo club. Intrigued by Kokonoe's skill, he tries to discover more about this mysterious student…