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. Having passed a century, a similar "disease" began manifesting itselves amongst the humans once again. But this time, humanity was ready for they have prepared for the day of the return of the Pecarre. However, the battle between two factions waged on for generations as the "disease" continued to spread rampantly. With no end in sight, humanity was once again tested to their limits, will they find a cure for this "disease" or will humanity cease to exist?