Sota, who married the daughter of the Ohara family as a son-in-law, was fascinated by the abundant breasts of her mother-in-law, Rio. - One day, Sota decided to help Rio stretch. - Sota, who has reached the limit of patience with the obscenely swaying huge breasts in front of her, attacks Rio. - And Sota, who also saw the weak personality of Rio, seeks her further. - The actions of the two escalated, such as playing with Rio's naked body full of bubbles in the bathroom, hiding in the family and immersing himself in affair.