A "disease" that took the world by storm rages through the human population, turning those infected into unrecognisable, bloodthristy monsters known to humanity as the Pecarre. In a last ditch effort, humanity managed to fight back putting the monsters at bay, giving themselves a chance to flourish once more. With that, a group named the Virtuoso was formed, a fighting force that were trained for one single goal and purpose. The elimination of the Pecarre.