「さすがに毎晩はかんなのセックスについていけないよ。どこかで発散してきたら？」その夫のひと言がきっかけでジム通いを始めた私。体力には自信がある方で、ただひたすらトレーニングに打ち込んでいるのですが、身体を動かせば動かすほど、無性にムラムラと感じてしまって…。そんな時、トレーニングルームの隅で優一くんと出会ったのです。器具の扱いに不慣れな彼に手取り足取り教えてあげていた私ですが、運動ともに大きくなっている彼のアソコに欲情してしまって…。

"I can't keep up with Kanna's sex every night. Why don't you go somewhere to release your tension?" That one comment from my husband was the trigger that made me start going to the gym. I'm confident in my physical fitness, and I've been diligently training, but the more I move my body, the more I feel uncontrollably aroused… That's when I met Yuichi in the corner of the training room. I was patiently teaching him how to use the equipment, but I became aroused by his penis, which was getting bigger with each workout…