It has been a few months since eldest son Tatsuya moved to Tokyo. He is lively and strong-willed, while younger brother Takumi is somewhat timid, but both were born from Towa Ko's "childbirth-ready" ass and have grown up healthy and rarely catching colds. One day, Towa Ko receives a message from Tatsuya saying he'll be coming home for a brief visit during work. Overjoyed and emotional at the thought of seeing her eldest son again, she enthusiastically cleans the house, vigorously shaking her huge ass. By chance, Tatsuya arrives early and catches sight of her like this... A story depicting how the family bond grows even deeper.