The shooting of Kaito has triggered a Flood in the normally emotionless Nagai, releasing a massive number of IBMs. Not wanting to miss out on the fun, Sato has matched his pace, and Iruma Base is overrun with countless black ghosts. Dr. Ogura, the world├нs leading IBM researcher, makes his way toward the heart of the chaos, even as the story barrels toward a moment of truth regarding the origin and very nature of Demi-Humans.