Kayu Tsukawa, who has a father who flies round the sector as an archaeologist, is attacked with the aid of his sister-in-law, Sanshi, who become dressed as a devil, even as being in a bondage the night whilst he lost his necklace from his father in childhood. Kaiyu, who is responsible of delusioning the loved Sako in her desires, is understood to the classmate Ryo Ruri, who's a member of the ethnic observe group of the college garden collectively, Ruri and Sanskyo. It is found out that the identification of is Nympho Succubus. Kayu, who has misplaced her mastered necklace, also seals Ruri's movements and squeezes semen. Sako, who had lengthy been surrounded by using magic via necklaces, attacked Kayu inside the rest room again with a separate character, and expressed his mind on Kayu, who grew up in Sakyo, and become so absorbed inside the act that she become exhausted. Further trouble occurs before Kayu is confused with the aid of her liked sister's transformation….