Military!

The story centers on the conflict between the Krakozhia Dukedom and the Grania Republic. At first glance, high school student Souhei Yano has nothing to do with this war. However, his father, an unassuming salesman, turns out to be a key figure in it: he is the hero who managed to turn the tide of battle in Krakozhia's favor just when Grania's victory seemed inevitable. But while his father is perfectly capable of protecting himself, the inexperienced Souhei finds himself in mortal danger.

Fortunately, Souhei is not left to face the threat alone. Grania's mercenaries hold no terror for him, because he is guarded by First Lieutenant Lutgalnikova and Second Lieutenant Haruka, who roll right up to his house in tanks. These seasoned soldiers are ready to stand in the way of any danger to keep the young man safe. Together they confront the enemy and try to survive a fierce conflict in which every step could be the last, while gunfire becomes a regular part of Souhei's once ordinary daily life.