Yuji, the son of a concubine, lost her parents and was taken over by her wife, Hanahoko. Hanahoko was not blessed with a child, and because of that, she was treated coldly by her father-in-law. Hanahoko's younger sister, Ayaka, who was worried, proposes a plan to use Yuji's sperm to make Hanahoko take care of her husband's child. At first, Hanahoko refused, but her instinct began to ache at her young and powerful penis.