In the midst of a war between the Krakozhia Dukedom and the Grania Republic, a high school student named Souhei Yano unexpectedly becomes the savior of the Dukedom. His peaceful existence is disrupted by the sudden appearance of two female soldiers, First Lieutenant Ruto and Second Lieutenant Haruka, who arrive in tanks and bring the chaos of warfare to his doorstep. Things escalate further when an enemy soldier, Shachirofu, joins the fray, turning Souhei's home into a battleground where firearms are wielded without restraint.