The Earth Exploratory Navy has slowly been losing territory over a long and terrible conflict. The Vekros continue to attack with no clear purpose other than to annihilate humanity. Elite weapons called Operators, developed to beat the impossible mission of saving humanity. Operators are no ordinary weapons. The men and women selected to become the Sword and Shield of Humanity fight valiantly. The sole purpose of fighting is all they know, with no shred of recognition, they will continue to serve. The EEN continues its ever slow advance to reclaim lost worlds. They set their sights to retake the core system of Kanto. Led by rookie commander, Valeriya Kurepina, the operators are thrust into bloody fight after another to retake Kanto-IV. The operators take on the challenge; against new threats, technologies, and pasts.