Since ancient times, the "Tōshi" (刀使), or priestesses of divine cutting, have been purifying the aberrant beings known as Aratama that threaten the human world with their sacred swords. This spring, an annual tournament is about to be held, gathering the finest Tōshi from the five schools known as "Gokaden" that train these warriors. Kanami Eitō from Minozaki Academy's junior high is preparing to participate in the selection battle to become the academy's representative—!?