My sister's friend was so horny that she had sex with them until they had children. ZUKO-063

Your younger sister, Riku, is a cheerful and lively high school girl. One day, while their parents are out, she brings her friends over. After forcing them to hand in their homework, they start doing lewd things. Worried, you go to the bathroom only to be surrounded and taken away by naked girls… In the end, you and your sister have unprotected sex…