Recently my wife has been on a diet, and it seems like she's addicted to watching some videos. It turns out that she's afraid of getting fat, so she watches and follows the exercises of a trainer in a weight loss exercise video. The trainer is Hibiki, a person with a perfect body and a beautiful face. It seems like her class is accepting new students, so my wife invited me to join. Hibiki guides me in a friendly and polite manner, but somehow the distance between us keeps getting shorter! Since guiding two people at once doesn't seem effective, Hibiki suggests teaching each of us separately, and I agree. The next day, Hibiki continues to focus on guiding me in the workout, but it seems like she touches me more, constantly revealing her chest as if inviting me. And she seduces me! I keep rejecting her because I have a wife, but the seduction of Hibiki is something no man can resist! After a while, my body becomes firmer and more muscular, and I'm not sure if it's the result of hard workouts or the endless lovemaking sessions with her, the female trainer...