Night after night, the same dream of a guillotine. A headhunting serial killer. And the "knights" in black who follow soon after. Irrationality that defies the realm of common sense begins to assault and devour the city.

In the near future, an ominous red star appears in the sky. Its presence is about to bring about the extinction of all life on Earth. The government proposes an evacuation project to take all of mankind into space. Ryou Haruna, a soldier, is sent to watch over Sion, one of the modified superhumans that are humanity's only hope for survival.

A woman with eyes of jade stands before You, informing You that You are the Master of the house, and she Your Maid. However, You have no memories, no concept of self, or indeed, any certainty that You are even alive.

On a secluded island named Rokkenjima, the head of a wealthy family named is near death, and eleven of his family members arrive on the island to discuss how his assets will be divided once he is dead. A typhoon traps them on the island and shortly after people start to get mysteriously murdered.

Spring. After the death of his father left him without any living relatives, Kusanagi Naoya is put under the care of his friend's family. There, his homeroom teacher awaits him. And with the arrival of the new school term, his childhood friend who transferred long ago reappears right before him.