07/04/2017
We had only been together for a few months when I suggested to my GF Jenny that maybe we should try having an "open relationship". She didn't seem that keen, but eventually agreed. I was happy because I thought it would mean I could fuck other girls, but I soon found how stupid I was.
We were at a party a few weeks later, and everyone was drunk and stoned, and I realized Jenny had disappeared. I asked around and someone said she had gone into the back yard to have a smoke with a big, red-headed biker guy called Ash.
I snuck down the driveway to the back yard so they wouldn't see me. It was very dark with only one light-bulb at the back door, but I could hear some quiet moaning noises. I pressed myself up against a tree trunk and looked around it, and as my eyes adjusted I could make out Jenny with this guy lying next to her. She was kissing him on the mouth. Her dress was pulled up and I realized he had his hand between her legs, inside her panties. My girlfriend's flat, white tummy almost glowed in the darkness, and I could see this guy's fingers moving under the white cotton. Jenny was making sexy little noises into Ash's mouth. I felt incredibly jealous, even a bit sick, but also very, very horny. As I watched I felt my cock growing stiff down the leg of my pants.
After a few minutes Jenny pulled her panties down and off, and pulled Ash on top of her. They dry-humped and kissed for a while, and Ash undid Jenny's top and pushed her bra up so he could get to her tits. After he had kissed and licked her tits for a minute, he kneeled up between Jenny's open legs and undid his jeans and pulled them down a bit. His cock looked big and fat and white, and stood out straight from his pubes. Jenny grabbed it with one hand and gave it a couple of tugs, then Ash leaned forward onto his arms and I got a clear view as his long white cock nudged against Jenny's dark-blonde bush before steadily disappearing inside her. She must have been very wet because it slid right in. She gave a little squeal when Ash bottomed out, and I could see his cock glinting from the wetness as it slid back out again. I could feel my dick leaking liquid down my leg.
Ash started slowly pumping in and out of my girlfriend, and a heard him tell her how good she felt. Jenny was moaning and whimpering, clutching Ash's arms and looking down at where his cock was disappearing into her, over and over. After a while she slid one hand down between them to touch herself and I knew it wouldn't be long before she came.
Ash picked up the pace and was thrusting hard and fast when Jenny started coming, panting and gasping and bucking her hips up to grind herself against Ash's groin. It was at this point that I felt a hot wave of horniness sweep though my body as my cock started squirting hot jets of jizz down my leg. It was all I could do to keep quiet as my body twitched and spasmed
Ash came soon after, giving a low growl as he suddenly froze, deep inside my girlfriend. He made no effort to pull out, but just held himself there, shuddering a bit as he ejaculated, squeezing out every last drop inside her.
Jenny had pulled him down onto her, wrapping her bare arms and legs around him, and kissing him some more, when the back door of the house suddenly burst open, flooding the yard with light, and a bunch of drunk people spilled out, laughing and whistling as they noticed the couple lying in the grass.
I didn't want to be caught perking, so I snuck back down the driveway and into the party through the front door.
The semen on my leg felt cold and horrible, but it didn't look too bad, so I got myself a drink and wandered around.
I didn't say anything when Jenny came up to me soon after, except that I was tired and wanted to go home. She didn't say anything either, but she must have known that someone would have told me what happened. We were both very horny when we got home, and it felt amazing to slide my cock into her, lubricated with another guy's come.