SSNI-845 The sadistic older sister Yua Mikami

Today my girlfriend's parents went on a trip, so I had 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 by her room I accidentally looked inside and saw a naked man crawling towards her feet, in her hand was a chain tied to his neck. At that time, I could not imagine that I would also be turned into such a person, her toy, her pet.