Since losing her husband, Yumi has raised her son Yasuo all by herself. Despite knowing about her son, she remarries a man named Kazuma, and the three of them head out for a day at the beach. As Yumi relaxes by the shoreline, Yasuo asserts that she belongs only to him, burying his face between her legs and caressing her voluptuous, soft body. Overcome by the warmth of her touch, Yasuo can no longer restrain himself and forcefully thrusts Kazuma's cock into his mother's mature pussy. On the quiet shore, the bonds of this twisted family grow ever deeper.