The previous night, Yoriko had a strange dream of red blood, a red moon, and beautiful red eyes. When she tries to remember more about the dream at school, she feels sick and her friend Kirin suggests she take a nap in the nurse’s office.
However, Yoriko stumbles upon danger when the nurse turns out to want to drink her blood, picking up from last night when she tried to eat Yoriko! Luckily, she’s saved...by Kirin, who has the same red eyes from her dream! It turns out both Kirin and her brother Koriyuu possess bloody abilities...because they’re oni! Now Yoriko is slowly being swallowed into their world of spirits, demons, and terror…
(Note: “Oni” are a type of Japanese supernatural monster, usually depicted as ogres or trolls with horns growing from their heads.)