Her husband would never do anal... or so she thought—until now. Aya Kisaki and her husband have been married for several years, and their relationship has gradually fallen into monotony. One day, her husband suggests anal sex. Though she refuses at first, the idea lingers in her mind, and soon she finds herself masturbating anally, fantasizing about it. Unbeknownst to her, young neighbor Takeshi is secretly watching. What begins as a private moment spirals into an unexpected turn of events as Takeshi takes advantage of the situation, stealing her away in secret. A forbidden story of temptation, betrayal, and anal indulgence unfolds.