With the launch of the first orbiting space colony, humanity looked to the stars with hope in their eyes for a more peaceful, prosperous future. The AD calendar fell to disuse as Orbital Era began. But in just 79 short years, a mere three generations, that hope was shattered when the colonies declared their right to self rule and waged war upon the United Earth Alliance. The United Colony Corps made it's declaration of war, then less then twenty four hours later attacked.
The war was short, but brutal. Great loss of life was suffered by both sides. When the UEA started to press its advantage in manpower and materials, taking the battles to orbit, the UCC responded by indiscriminate bombardments of the planet's surface. Several colonies have been reduced to shattered ruins and several nations of Earth have been laid low... or even outright destroyed. In the face of such horror, the UEA was pressured to accept an armistice from the UCC by its citizens, despite victory being in sight.
It has been a year since the war's end. Nervous eyes have been turned to the sky. The UCC is preparing for the next war. For this, they are readying the next step in warfare, seeking to replace the slow and bulky Phalanx Power Armors with something smaller, faster, harder hitting, and infinitely more dangerous... the mecha musume.
A collaborative project between the UCC and the colonies military-industrial complex, the mecha musume are a highly experiemental black book project... as well as a highly unethical one. This is because the musume, formerly human, are not created from willing volunteers. Cupidity, expedience, and a particular lack of moral fiber have come together to produce a manpower solution: the UEA's P.O.W.'s and M.I.A. from the war!