In order to attend my college, I stayed at my brother and his wife's house. One day, my brother had to go abroad for a few months.

So, I started living together with my sister-in-law, Uenohara Ringo-san.

"......Rikuto-kun."

A quiet house with almost no noise. In a room where I couldn't even hear the sound of the television, I thought I heard Ringo-san's voice. From somewhere, I felt like my name was being called.

"Probably just my imagination?"

I tried to listen closely, but I didn't hear any voice. If Ringo-san did need something from me, she'd have call me again. It was too early for dinnertime, there was no reason for me to be called at that moment. Perhaps she was doing housework, and somehow uttered a sound that was similar to my name. If she were to scream, then I'd have to check it out though.

At that moment, in order to calm her burning body, Ringo is masturbating alone. She imagines doing it with her husband, but eventually, her imagination becomes "Rikuto...."