Oni-Gokko

The only fragments Yoriko could recall from the previous night were a spill of crimson blood, a blood-red moon, and an impossibly captivating red eye. The next day, struggling to piece together those hazy memories leaves her feeling ill during class, prompting her classmate Kirin to suggest she rest in the nurse's office. Upon arriving, Yoriko finds the room empty and settles into an unoccupied bed. But her brief respite is shattered when the absent nurse returns—not to tend to a student, but to complete a task she failed the night before: draining Yoriko of every last drop of blood. Just as the attack escalates, Kirin bursts in to rescue her friend from the demonic nurse. In the aftermath, Yoriko learns the truth: Kirin and her brother, Koryu, are not human—they are oni.