[Stareman7]

After my BIL's (wife's brother) bachelor party, we ended up drinking in the backyard of my other BIL's (wife's sister's husband) house. I had to take a leak, so I went around the corner to go in a flower bed. As I was finishing, I saw the lights come on in the bedroom by which I was standing. My SIL (wife's sister) walked in from the bachelorette party and began taking off her shoes. Because of the way that the shades were downturned, I could see in the room as if I were standing in it. I got butterflies in my stomach because I knew what was about to happen and immediately got rock hard. She unzipped and dropped her skirt and pulled her shirt over her head and was standing there in thong panties and a skimpy bra. I started stroking even though anyone from the party, including her husband, could have come around the corner at any minute. She removed her bra (small but perky tits) and then steadying herself (had been drinking), pulled down her panties (hairy light brown pussy...little lighter than my wife's...and slightly protruding pussy lips.

She grabbed another pair of panties from a drawer, sat on the bed, and began to lift her leg to put them on. I could see right between her legs and started shooting streams of cum. I zipped up, went back to the party, and within a few minutes got a hug from my now fully dressed SIL.

I have never seen her naked since. It was risky, but well worth it.