Your biggest weakness is your attraction to me, your irresistibly hot step-sister. I know this and it just drives me to cocktease you even more. For that reason you decide to lock yourself away in chastity to prevent further damage being done. Somehow I manage to convince you to hand over the keys, and that's when everything changes. A week in chastity passes, and I just amp the teasing. You soon realize that you are putty in my hands and this will be lasting far longer than the originally intended week.