Yui Hatanoh, a modest married woman suffering from a sexless marriage, anxiously visits a fertility treatment website after constant pressure from her parents to have a grandchild. There, she meets a seductive therapist who invites her to undergo intense training to enhance her feminine allure. While convincing herself it's all for her husband's sake, she resists losing her chastity at first—but gradually gets drawn deeper into the sessions. As the therapist subjects her to relentless stimulation through expert cunnilingus, vibrator play, and sensual massage, her body begins to betray her. The overwhelming pleasure and temptation slowly erode her resolve, leading her toward forbidden creampie encounters and ultimate NTR betrayal, all under the guise of therapy.