Overview:

Dead bodies with eyeballs ruptured are continuously found. Their direct causes of death are heart attacks and they acted like they were possessed right before their deaths. Mizuki is a university student. Her friend dies in front of her. Meanwhile, Haruo’s younger brother dies. Mizuki and Haruo begin to investigate together. They learn that Eiko holds a key to the mystery. Soon, Eiko's eyeballs rupture and she dies by a heart attack. Before she dies, she mentions the word "Shirai-san.”