My girlfriend is naked in the'naked'house. Her younger sister Haruka will stay for two weeks in the summer class at the prep school. Haruka-chan, who gets naked in greetings, is thrilled! Even if I was told, "It's natural because I'm a family member," I'm looking at the G-cup boobs and crotch. "Huh? You're getting an erection! Sneak out and Agel" and a blow job outbursts right next to her! Haruka-chan, who is fearlessly set up even when she is in the bath or sleeping, ... and I'm erected.