Siege of the "Monster Association" by the "Heroes Association", U're a hero remained on the surface with other heroes, guarding a child hostage who was rescued from the monsterkind a few minutes ago. Now it's u and companions killing the monsters that came to the surface, those who strayed from the conflict with the S-class heroes underground, 'til u see it... Hero "One-Shotter" shoots at that cat but the shot's returned, in a blink of eye; Many heroes torned, Nyan in front of you. "I'm Nyan, one of the Cadres of the Monster Association... That said, I'm going to slaughter you all."