*simulated penetration and creampies* youre letting your pregnant sis stay with you until she transitions into her new home and she cant possibly thank you enough. she mentions that if there is anything at all she can do for you to return the favor she'd be more than willing to do so. you mention something about her being free use, but she doesnt exactly know what that means.. like have intercourse with her whenever you want? your own step-sister?! i guess since shes pregnant, theres not really much that could go wrong and she does owe you big time.. but itll only be for the day, and if you both really like it maybe it can be prolonged to a week..