Asahi, whose hobby is muscle training, learns that his son's friend Kentaro is not getting enough exercise, and tells him about various things. The size of her crotch that she touched by chance reminded her of her sexual desire that could not be extinguished by training alone. And Chaoyang, who lost her desire, seduced him with his cock. However, she continued to raise her voice in agony as her body climaxed many times due to his unfaithfulness that did not end with just one or two times. Chaoyang finally gives up on the unmatched copulation with him that seems to be forever.
