She, The Ultimate Weapon

In a high school in Hokkaido, students Shuuji and Chise navigate their everyday lives. Chise, a shy and introverted student, is on the verge of confessing to Shuuji. However, their lives are disrupted by a sudden air raid on Sapporo. As Shuuji tries to escape, he witnesses Chise wielding a powerful and mysterious weapon, taking down enemy fighters with ease. It is revealed that Chise possesses a destructive power that is crucial to the war effort, making her the ultimate weapon.