Tatsuya sees off his wife, who is about to give birth and returns to her parents' home, and then busies himself with household chores. Feeling lonely in the empty days without someone to talk to, he feels a sense of solitude. Just then, his wife's sister, Mai, comes to check on him. Tatsuya welcomes Mai, delighted to have someone to talk to after so long, but... Mai's true intention is his body. Suddenly, Mai barges into the bath. With no way to escape, Tatsuya is cornered by Mai's incredibly bouncy and fair-skinned breasts, leaving him with no means to resist...
