Stepmom teaches me how to fuck her to have multiple orgasms

Since it was just the two of us in the house, stepmom used to walk around in her panties and went without wearing a bra and only wearing a t-shirt. She had a great shape and nice tits from the outline of the t-shirt. Her nipples always seemed to be hard and erect too. She was certainly a vision of loveliness with her long blond hair. Many a time I fantasized about fucking my stepmom and then retreated to my bedroom to jerk off. I didn't have many friends, just a couple of guys from school and since I went to an all boys school, I surely didn't have many girl friends. I used to stay in my room and surf the internet a lot. One day I found a porn website featuring young men fucking their stepmoms and, as I watched, I thought about doing my stepmom and then jerked off. One day, I was watching some porn and my stepmom knocked on my bedroom door. I quickly put the cover on my laptop down so stepmom couldn't see anything.