Empire Katvarna and Kiokskaya Republic at war. Katvarna protect their borders from attack Kyoko. Yatorisino, heiress to an influential family in the empire, passes examination for promotion to the rank. Also pass exams and to help it to accurately deliver among the best students, she convinced Ikuta, a pacifist and a lazy womanizer,in exchange for support from her family. The first written test goes as planned, and then they are sent to the ship to the next stage. Unfortunately, the ship is sinking and Yatorisino, Ikuta, other students, and a mysterious little girl find themselves in enemy territory. this 17-year-old young man to go the way of the great commander, surviving in the world, absorbed by the war, thanks to his brilliant mind.