Blasting away threats to protect the world — that's our everyday school life. Kotoba Kazuha, a boy with a shady past working under the mafia, had given up on having a normal youth. However, his encounter with a group of extraordinary girls changes everything. Together, they take on mysterious beings threatening humanity, wielding massive guns with reckless abandon! Behind the scenes of the world, a wild and chaotic youth unfolds! A giant-sized series packed with sci-fi, romance, action, and all the fun you can imagine — let the explosive story begin!