While jogging, I noticed a woman running unsteadily with poor form. I called out to her out of concern, and it turned out to be Yua, a married woman who lives nearby. I couldn't stand to watch her, so I decided to run with her as her coach, but... her body is too erotic! Her huge breasts that couldn't fit into her sports bra jiggled every time she ran, and her plump butt meat wrapped in shorts bounced around, making me unable to resist getting an erection at the sight of her powerful and selfish body. Then, when Yua looked at my crotch, her sexual desire was also ignited. From that day on, I indulged in extramarital sex no matter where it was, whether it was at home when her husband was away, or outdoors while running.