* Based on a horror/mystery novel by Ayatsuji Yukito, serialised in the Yasei Jidai. A prequel episode to the series that shows some of the secret meetings of the separated twins Fujioka Misaki and Misaki Mei, providing additional context to the scene in the first episode where Sakakibara Kouichi meets the latter of the two in a hospital. Note: Episode 0 bundled with the 0th limited-edition volume of Kiyohara Hiro's manga adaptation of Ayatsuji Yukito's novel.