Humanity is suffering from a series of mysterious murders across the globe, known as the 'Mincemeat murders'. High school student Izumi Shinichi has a parasite living off him, having replaced his right hand, and he might be the discoverer of truth.

Humanity is under attack by human-mimicking flesh-eating alien parasites. One parasite bonds with his young high school student host, and he convinces the parasite to help him stop the others.