Squirting Stepdaughter Joins Bath With Stepdaddy

You are enjoying a relaxing bath when your 19 year old smoking hot stepdaughter decides she wants to take a bath too, at the same time with you! Since your wife is not at home you reluctantly agree just as long as she wont tell anyone. Soon her top comes off and she washes every part of your body with her soft hands. Your cock can't help it but it gets hard as crowbar. What will your stepdaughter decide to do with your cock? Few days later, you are jerking off in the bath all by yourself when your devious stepdaughter just jumps in with you. She says she has had a crush on your forever and all she wants is for you to fuck her like your fuck your wife! What should a good stepdaddy do at this point?