story:

Episode 1: Goodbye, Summer Days

Shinpei Ajiro returns to his hometown of Hitogashima Island after two years to attend the funeral of his childhood friend, Ushio Kofune.

He soon discovers that Ushio may have been murdered, and he begins to investigate her death.

He learns that Ushio was found drowned, but there were bruises on her neck that suggest she was strangled.

Shinpei also learns that Ushio's family has a history of Shadow Sickness, a disease that causes a person's shadow to come alive and kill them.