Nagato Kazuya, a “Military Nerd” high school student who gains the ability to summon modern-day weapons and soldiers, when he reincarnated into another world.

Together with his summoned yandere military advisor, soldiers and modern-day weapons, they will conquer the land, seas and skies of a fantasy world.

These are the unparalleled existences of his yandere harem and their stories of combat.