Your big titted step-sister has noticed what a disgusting pervert you are, getting boners all the time while staring at her tits! She surprises you by calling you out, and brings along a new discovery - a steel chastity device. After locking your pathetic step-brother dick up, she teases you with her big tits and taunts you as you feel your dick pressing hard into the steel. She might be willing to let you out - if you help her with some chores and errands! Step-sis is tickled by the idea of having your horny dick under lock and key - and if you disobey her, she'll expose you to our parents!