My father remarried and we got a step-sister, my sister and I. She's bright and beautiful, but my eyes keep going to her breasts and ass... One day, I was seduced by my step-sister and forgot myself and had a physical relationship! If my family found out about this... But even my serious sister was taught good things by her step-sister, and before we knew it, we became a relationship where the three of us have sex in secret from our parents!