My parents remarried and I got a new sister-in-law, who is the polar opposite of me in terms of personality. She's a slut who loves sex and brings guys over and has sex with them whether I'm there or not... I can't stop getting horny in that situation... My sister-in-law noticed and started to teach me the ropes! At first, we did a little development together. Then, a man joined in and we had a full-scale erotic training! Now my sensitivity and technique have improved and I enjoy having sex with my sister-in-law! Just like my sister-in-law said, the one who enjoys sex wins.