My reliable senpai, Ayami-san, always covers for my mistakes. One day, after missing the last train at a company gathering, I ended up having a nightcap at her place. Her casual, braless attire, with her nipples clearly visible, was incredibly alluring. I couldn't help but get aroused by this side of her that I never see at work. Her sensuality drove me wild, and despite having a girlfriend, I couldn't resist repeatedly betraying her with passionate sex, teasing her with my 3cm cock.