Those capable of manifesting weapons from their souls are known as Blazers, and they enroll at Kouryou Academy High School to master these abilities. Every student must form a partnership with another, aiming for the day when the duo can achieve the power of Absolute Duo. Tooru Kokonoe aspires to join this academy to acquire strength following the murder of his sister and friends by an enigmatic man. Yet, during the opening ceremony, he is compelled to duel the person seated beside him, with expulsion awaiting the loser. Just as Tooru readies himself to fight with everything he has, a shield rather than a weapon emerges from his soul—an anomaly that draws the notice of a foreign student named Julie Sigtuna.