Half-Sister and our Great Dane

[b]When I was 13 I was headed to my room one evening and heard some really strange noise coming from my Sister’s, Linda, room. I pushed the door to her room open just enough to be able to see what was going on and there is Linda sucking our dogs huge cock. She is turned so that roscoe is licking her cunt while she sucks his cock, she is moaning more and more as he he licks her cunt and she is increasing her tempo as she bob’s up and down his swollen member. Unknown to me why, my cock is growing inside my jeans, getting harder than I can ever remember it being. I am amazed by how she can take his cock all the way down to this huge swollen part at the base of his cock. His cock had to be 10″ and she was swallowing all of it.

Now I had my cock out and was stroking it, imaging Sis was sucking me and it wasn’t long before I shot a huge load of cum all over the wall. I ran to my room and grabbed my Polaroid camera and went quietly into her room, she was too occuppied to notice me and I snapped a picture of what she was doing. The flash caused her to pull off Roscoe and as she did cum was spaying all over her face. ” What the fuck do you think you’re doing ” she yelled. I looked at her cum soaked face and said ” I think you’re going to do anything I want or Mom and your friends see this picture”. ” Just what is it you want?” she asked. My reply “sex, any time and how ever I want it.”

I told her that since Mom was going to be gone for the weekend our first session would take place then. Saturday finally came and Mom left I told Linda to get undressed and follow me to the shower. We got into the shower and I told her to wash me, which she did and when she got to my cock and balls she slowly soaped them and started stroking my cock.