Seven years into marriage, Yuko undergoes fertility treatment after failing to conceive. While her husband waits in another room, she undergoes a genital examination and involuntarily lets out a sweet moan. The doctor, trembling with excitement, uses the treatment as an excuse to aggressively stimulate her sensitive areas, causing Yuko to give in and accept his much larger real cock, far bigger than her husband's. Afterward, addicted to the doctor's technique, she transforms into an unfaithful wife who ends up sucking his cock right beside her own husband.