My father remarried and my younger sister and I got a new step-sister. She's cheerful and beautiful, but I can't take my eyes off her breasts and ass... Then, one day, my step-sister seduced me and I lost control and we ended up having a physical relationship! What if my family found out about this...? But my step-sister taught my honest sister what felt good, and before I knew it, we were having sex together, hiding it from our parents!