I hadn't been exercising lately, so my body had become slack. With my wife's encouragement, I decided to ask Yu-i, a friend of my wife who used to work at a gym, to teach me training. Even after marriage, Yu-i continued to work hard on self-training, and she had a very beautiful body. Just the thought of training alone with her made me nervous inside. On the day, as Yu-i, dressed in sports wear that fit her body, taught me muscle training step by step, I unknowingly got an erection...
