School. Biology Room. Night. Kai, who has come to pick up Saya, witnesses an incredible scene: her sister covered with blood is fighting with a sword against a creature beyond any description. Then Saya faints on the spot... The next day, the incident is treated as a murder committed by a drug addicted American soldier, and there seems to be no trace of the creature. Taken to the hospital from school, Saya accidentally hears the conversation between George and David, a mysterious man who watches over Saya. And what she hears makes her run away terrified...