Aoi (Miori Hara), who is on the way home, is attacked by a mysterious beast man and is killed after being fucked. At the strange research center specializing in cases that cannot be elucidated by ordinary recognition, commonly known as "Kisoken," the staff members Hongo and Maki (Yukine Sakuragi) are inspected. Then, the same infectious virus as the similar case that had already occurred three times is detected from the collected cells. The source of the virus is still a mystery, but it is certain that it will be infected and die by sexual activity with the owner. But the most scary part of the virus was that the dead were resuscitated and spawned new infected people.