As a student, Kozono becomes both the victim and perpetrator of dark magic rituals. She is magically seduced by the unpopular Academy student [Hiratani](https://anilist.co/character/26131). When released from the spell, she unsuccessfully attempts to gain the Devil's power herself by joining [Hiroko Takashiro](https://anilist.co/character/18612)'s witchcraft club and kidnapping [Reika Kitami](https://anilist.co/character/26132), the newly transferred student she develops a crush on.

Based on the erotic game by Active. 
Minase, a high school student, found a book of magic in an isolated room in his school. He started practicing black magic that has extreme sexual effects that benefited him and some of his friends. Intrigued, Minase got deeper and deeper into using the craft, not realizing the evils that will come forth. Eventually, the origins of the book was revealed, and so did the incident twelve years ago on the night of the Walpurgis, the night when the power of evil is at its strongest. After coming to his senses, Minase struggles to get himself out of the darkness that he had put himself into.
 
(Source: Anime News Network)

Based on the erotic game by Active. 
Twelve years prior to it's discovery by Minase, the origins of the magic book with dark,sensuous powers is revealed. Initially owned by a female student, Takashiro, who, along with other curious students form the first magic club on campus. The club begins to use the erotic spells to carry out favors for fellow students, and vengeance. After underestimating the powers behind the book, Takashiro is taken out of the picture, as a new leader guides the club towards a darker course, one that will force school newcomer Kitami to make a dire choice.

Nami Kozono