Yumi was dumped by her sex friend because her libido was too strong. Takuya has an extraordinary libido. The two meet and have sex. Both are confident in their libido and they fight for dominance, but Yumi loses. Seeing Yumi fretting over how to win, Takuya's mother gives her a secret medicine that is the source of her libido. She drinks it hesitantly, and her body heats up, gradually becoming lustful. Now they're on the same page. Revenge begins.