Step-Mommy Reluctantly Fucks step-Son JOHN

We have gone away on a family trip and all sharing an apartment (2 bedrooms and a pull out sofa bed in lounge where you are) You are a s leep on the sofa or bed, ideally in a white sexy night gown but other colours work too with no bra or panties. Your lying on your side, blanket over you but cleavage exposed (if poss) and I walk in to get a glass of water. Seeing you there is a turn on for me and I want you. I start subtly by putting my penis in your hand, getting you to grip it. Then I put the tip of my dick in and out of your mouth, slowly putting in more and more before waking you as I am deep inside your mouth. You are startled, shocked and annoyed. trying to pull away from me - I tell you to be quiet not to wake anyone and this is what I want. You don't want this, saying you can't suck your step-sons penis but I push your hands away and put myself back inside your mouth to keep you quiet! A look of shock on your face as you pull away and beg me to stop (all in a quiet voice). I will only stop once I am inside you and fucking you, i lye behind you, lift up your leg and start rubbing your pussy, getting you wet (say on your side). When I want to, I put my cock inside you and fuck you, slowly to start but my thrusts get harder and faster to hear your ass slapping against me. Then, I pull you on top of me, you are going to ride me, all the time whispering how wrong this is and how I have to stop. You are my step-mother and I can't do this too you! The only way I will stop is when I cum and mummy needs to beg me to cum inside her or we will keep going......