【BL/YAOI - OMEGAVERSE】Earth is now known as Ancient Civilization and is infested with creatures called Devourers. The survivors live in space stations and try to find a way to rebuild their lives. Callan is one of these survivors. He was on a mission when an attack separates him from his boyfriend. When they finally reunite, Callan realizes that something happened to the person he loves and, from that moment on, the choices he makes can lead to the destruction of what is left of the human race.