In a distant future, a group of settlers in an alternate dimension rebels against Earth, sparking a multi-dimensional war. As the conflict escalates, the United Army of Earth launches a massive offensive using cutting-edge weaponry called 'Assault Girls.' Piloted by societal outcasts and criminals, the 13th Independent Assault Girl Hunting Platoon, known as 'The Hyena Platoon,' is assigned the dangerous mission of eliminating rogue Assault Girl pilots corrupted by the perils of warfare.