The first time I did it, my sister Fawn got pretty fucking mad at me, but after a while she came to understand the situation could be a mutually beneficial thing for the two of us. I really couldn't blame her for getting mad at me, I mean I did sneak into her bedroom and watch as she let her boyfriend fuck her. It was what happened after that, after she got over her anger that was amazing.
It started out during our summer break from the university, Fawn was getting ready to start her senior year and I had just finished my freshman year. Our parents were traveling abroad so we had the house all to ourselves that summer and Fawn who was dating several guys at the time quickly began taking advantage of the situation. I had gone out with one girl a few times during the year, but nothing ever came of it, so I, most decidedly, wasn't taking advantage of anything. That is until the day I decided to slip into her bedroom and hide in the closet while she was out.
Fawn had gotten into the habit of bringing her boyfriends back for a quick fuck just before dinner time and then leaving with them to go out for dinner. After a few days of listening to the wrestling and moaning going on in the bedroom next to mine, I decided to get a closer look. Wearing a loose fitting pair of shorts, I slipped into her room and hid in her closet and, sure enough, within about fifteen minutes she came walking in dragging one of her boyfriends behind her.
Well, they seemed to be in a hurry because after only a quick kiss, the two hurriedly undressed. It had been a while since I had seen my sister naked, so I savored watching her peel off her bra exposing her nice sized breasts. Her nipples weren't very large but when her boyfriend quickly sucked one and then the other I saw they did perk up very nicely.
Slipping off her pants, I got a nice view of her bush. It looked soft and furry and I wondered what it might feel like. Her boyfriend's hand quickly hid it from view as I watched him slip a finger into her pussy shoving it in and out a few times. After that, fawn seemed to leap onto the bed, spreading her legs wide and he crawled on top of her, just like that. Ten seconds of foreplay and he was shoving his cock into her, what a waste, I mean although she was my sister, there seemed to be a hell of a lot of fun little curves and crevasses that needing touching, kissing and licking and here this brute was only interested in getting his rocks off.
With my viewpoint from behind him, I could see his cock sliding in and out of my sister's pussy, but after only about six or seven good thrusts, I heard him moan loudly, arch his back and obviously come. He remained on top of her for a minute or so, then climbed off and pulled on his underwear. He quickly got dressed while my sister grabbed a bathrobe, wrapped it around herself and they walked out the bedroom door.
She obviously wasn't leaving so I had to hurry to slip out of her room as she walked him to the door. Although the performance had been underwhelming, I did have an erection, but made not effort to conceal the tent in my shorts since I only planned to slip into my room and jack off. Well, apparently she let her boyfriend find his way out because as I got to about the middle of Fawn's room, her door opened and there she was.
Initially she didn't do anything, she just stared at me. All I could do was stand there, my hard cock bulging in my shorts, and watch her. Finally after nearly thirty seconds she said loudly, "You fucking peeping Tom," and rushed at me, swinging her hands slapping me on the face and head.
