SSNI-845 The sadistic older sister Yua Mikami

Today, my girlfriend's parents are traveling, so I have the opportunity to go to my girlfriend's house for the first time. I didn't know she had a sister, so when I passed her room I accidentally looked inside and saw a naked man crawling to her feet, with a chain tied around his neck in her hand. At that time, I couldn't imagine that I would also be turned into such a person, a toy, a pet of hers.