I slowly picked up speed, pumping harder and harder. I was so close to cumming! I had become so preoccupied with jerking off i didn’t notice my sist...r moving around a little more, and opening her eyes. I blew my load all over her face and bed and continued to slowly pump. When i looked back down, i was horrified and so worried. She was sitting up wiping the cum off her face. Groggily she said “what are you doing? What the hell is this?” all i could do was stand their, my raging hard on still. I looked her up and down as we stood. She wore tight trousers that bulged with the curves everyone so loved. As she turned around the outline of her knickers was clearly visible, and her boobs strained her tight top.She suggested we ride together which I of course agreed to, but the path was quite narrow, so I managed to spend most of my time behind her watching her arse as we rodeAfter about an hour we stopped for lunch and drinks sitting on a bench overlooking the river. As soon as we stopped. Dave's work car was in the driveway when they pulled up. Brittany felt her stomach drop because she knew the moment of truth was here. She would have to confront him about what he watched her do in the car. She knew he seemed okay with it at the time but the possibility of him reacting badly about it with hindsight was still real. She also knew that it was only a matter of time before she would have to tell him what the doctor had to say and she knew he wasn't going to be very happy about. ” “Just one. I’m sorry.” “You will be. First you steal a biscuit when you’ve just had a perfectly good lunch, then you break one of my special plates and to cap it all you tell me lies. Go to your room while I decide how to punish you.” I went upstairs with a feeling of dread, knowing that I would be punished after dinner and Kate would see me being spanked. Though the fact that I would be partially dressed in front of an 18 year old and her attractive mother who my mum had said was about.