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's 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.