A promiscuous kickboxing trainer at the gym sets his sights on beautiful office ladies. His first target is Minami Hoshino, a gorgeous big-breasted woman with three months of gym experience who diligently completes mitt training and other lessons. Afterward, while stretching, he gropes her body relentlessly and then proceeds to assault her. His next target is Misaoki Okumura, four months into training, whose gentle demeanor contrasts with her increasingly erotic large breasts. The sight of her big breasts bouncing as she's pounded captivates anyone watching. Engaging in sex at the familiar gym setting intensifies the taboo thrill, heightening excitement without a doubt.