Centuries ago, humanity's natural enemy, Demons, invaded the world and defeated humanity. The Great Demon King and his generals have since dominated the world, while the human race lives on in fear. In desperation, a group of 47 people gathered from around the world undertake a last-ditch effort to save humanity from ultimate annihilation. These heroes swear to defeat the demon army and win back humanity's freedom, but they have no idea the desperate measures that this battle will drive them to embrace...