After thousands of years, Humans have reemerged to the Earth's surface following a mass-extinction event. Demonic-looking monsters now rule the world where humans engage each other in a Civil War. One side, the Guerrillas, seek to destroy the Demons while the other, the United, seek to conform to them. This series follows an elite group of Guerrilla soldiers, called Rangers, as they become a part of the attempt to commit mass-genocide against the Demonic race.