Slut next door

“Oh God, oh God, oh God,” I heard her moaning through the window next door for the third time that night. They had been fucking all summer, loudly. At first I was annoyed, she was a good friend at the time and in the end she chose the neighbor over me. I was depressed in the beginning, being able to hear her moans and screams of pleasure through the open window just made me sad. After a week or so of feeling sorry for myself and I started looking forward to the sounds of their fucking, I started standing by my window and listening intently rubbing my cock furiously to her moans of ecstasy, picturing myself entering her tight pussy. This night was no different, I was stroking myself intently to her moans but I needed more. I was no longer content just listening, I needed to see the sweet little girl I had known since high school getting rammed so I started to make a plan.
We live in a side by side duplex and my rooms window extended to a roof, I had gotten to know my neighbor Nathan on that roof. We would climb out and drink and smoke during the school year and in that time we got pretty close, as a function of our friendship Rena and Nathan ended up getting together. Despite my initial heartbreak at the situation we all got over the awkwardness of it and I had ended up smoking a post sex cigarette with Nate a few times, catching small glances of Rena in nothing but her bra through the barely open curtain.
Those stolen glances only helped to fuel my fire, since I had met her I had been entranced by Rena. She a little shorter than me standing at 5’5” but despite her size she had legs that could rival nearly any models. They were long and smooth and led up to a somewhat flat ass that had just started to fill out a little. Her torso was short and she had small tits that I had caught a peek of once or twice over the years thanks to low cut shirts and somewhat oversized bras. Her body was slender and nothing to really remark about, her face was another story. She was half Thai and half White, which gave her a beautiful light brown complexion and some of the fullest lips I had ever seen. I had fantasized about those lips wrapped around my cock so many times I had lost count after a month of knowing her.
“Oh oh oh oh,” she was getting close to cumming and so was I. I shot my load into a towel and decided to see how far out of the window I could get before anyone noticed. I climbed out and sat on the sill as quietly as I could acting like I was about to light up just for cover. After a few seconds passed and there were still moans coming from the net window I stood up and took the step and a half necessary to get to the edge of the window. I waited another few seconds and poked my head slightly around the corner, and there she was riding his cock in full force. Her hands were planted firmly on his chest as she bounced up and down on his cock. Her long brown hair was bouncing wildly in the glow from the TV and I was instantly hard. I started to slowly rub my cock through my shorts as she stopped bouncing and just ground her pussy on his cock.