Plot Summary

I used to live with her. One day, her older sister Marin came to stay with us for a week. After that, I couldn't help but worry about the exposure of my sister's unconscious underwear and nipples. I was so excited and lustful for her that I finally couldn't control it... I secretly had runaway sex with her. "Oh, I feel my boyfriend's eyes on me..." My groin is full erection with the too erotic body line and chirarism of Takamine's girlfriend's older sister!