Yuka has raised her son, Kosuke, with her own hands. - While having evil feelings for her son, who gradually resembles her late husband, she was venting her unfulfilled desires within herself. On the other hand, Kosuke also secretly has more love for his mother than a parent and child, but he hides it and spends his daily life. However, on the eve of his marriage, Yuka, who peeked into masturbation, gently squeezes the meat stick that warps and erects, saying, "It's the last night spent with mother and child ...". However, the two people who do not fit in there are unable to stand it and are driven by forbidden lust ...