On the first day of the long holiday, my mom went to visit my dad who was working away from home, and my sister and I were left alone until the end of the holiday, five days later. A stranger broke into our house, aiming for that moment! The perpetrator tied me up and raped my sister right in front of me! I wanted to help her, but I couldn't! But I got excited seeing her face as she was being raped, and got a scum rock hard. On the third day after the break-in, I witnessed my sister cumming on the perpetrator's dick...