Kirioka Satsuki returns for a classic creampie drama. Mother Satsuki has always felt an unexplained attraction to her accomplished adult son Kosuke, while he secretly loves her too. Both suppress their feelings because they believe their bond can never become sexual. Then the hospital reveals that Kosuke was switched at birth and they are not biologically related. Confused but finally free to acknowledge their desire, they share deep kisses and surrender to repeated breeding sex and creampies.