Sayoko infiltrates Mikami College as a temporary counselor to investigate a mysterious drug ring. Amidst a school plagued by corruption and hedonism, she is tasked with assassinating the chairman, Aiko Nogami. However, her mission is jeopardized by an accidental witness, uncovering a dark secret: Aiko is far from human.
As a mysterious new student arrives, a sinister plot involving soul pacts and blood extraction unfolds under the full moon. After Junichi rescues a vulnerable Ms. Sayoko from the streets, he becomes a target of the conspirators for knowing too much. However, Sayoko awakens and vows to protect Junichi from the dark forces surrounding them.