Manami Oura, a young married woman, suffers from loneliness and sexual frustration due to her husband's constant business trips. Her father-in-law, noticing her vulnerability, begins making advances under various pretenses. However, her cautious and principled nature makes her difficult to seduce. Determined, the father-in-law devises a bold plan: he secretly laces every drink in the house with a powerful aphrodisiac. When her brother-in-law visits, he too falls under the drug's influence and gives in to his desires, leading to intense, unrestrained sex with Manami. The father-in-law, now fully aroused, joins in, followed by the brother-in-law's friend. Fueled by the overwhelming effects of the aphrodisiac, Manami's suppressed desires spiral out of control, driving her into a relentless frenzy of passion.