The narrative takes place during the sengoku era. a wandering swordsman known as nanashi rescues a young boy named kotarou at an abandoned temple. kotarou lacks family ties and is being pursued by a mysterious military force from china, which employs rarou, a skilled warrior with blonde hair and blue eyes. he follows the orders of byakuran, an elderly man who leads the chinese militia. unlike his comrades in the militia, he does not serve any emperor and is solely motivated by combat with powerful opponents.