Once a detective specializing in undercover operations targeting married women, Kana retired from active duty after getting married. However, she's pulled back into the world when her former superior, Yamada, asks her to help secure female subjects for a married woman molester operation. But soon, Kana becomes the target herself. She notices his presence, and gradually finds herself drawn to him. Overwhelmed by intense, penetrating sensations, her body quickly loses all resistance. Though trembling with humiliation, her body instinctively responds, craving more pleasure. Returning to the train, she eagerly awaits their next encounter.