Here is what happened after our initial visit to a female work colleague and her partners hot tub the other Saturday , as I and my Wife Amy have been thinking about buying one , it didn't end up quite as expected , but turned out to be a very enjoyable night for all of us and we got a open invite to go back anytime . Well Amy and I chatted about what happened that night when we got home , she told me she never expected what happened, but that she had loved the atmosphere of the hot tub and that riding our bikes over to Tina & Rob's house her bikini which she had on under her skirt had tucked itself between her pussy and had been rubbing against her clit all the way over and when she got in the tub and Rob ran his hand along her inner thighs it was enough to make Amy cum straight away. Amy also said she found Rob interesting and quite sexy even tho she said well he is a bit rough around the edges and when she felt the size of his cock it had turned her on even more and was eager to see and feel it inside her, she also admitted it was a turn on to see Tina playing ,sucking and riding my cock . I told her I felt the same about watching her with Rob and seeing her take all of his big cock and even tho Tina is not my type we had some fun and I thought we had all enjoyed ourselves . I went into work on the Monday , an before long Tina came over to chat with me and ask what we had thought of Saturday night, I told her we had enjoyed ourselves and she said they had as well and later on the Sunday , Tina said she kept catching her 2 Step- Son's and Rob talking about Amy every time she came back in the room , so Tina thought they were all well impressed with Amy and her body. Tina went on to say she was surprised by Amy , as I asked why ! , Tina said well considering she has a face on her that looks all sweet an innocent , she turned into a dirty slut in no time at all , even Rob couldn't believe how horny she was for his cock and also that she let both lads have her as well , he even said he would love to meet up again sometime and that both lads were keen for a repeat session . Well that was something that didn't take too long to happen, as I guessed something was going on as Amy decided to go running in the evenings , something she has shown no interest in doing before , I would watch her put her shorts and vest top on with her sports bra as she needs that as she has a nice pair of 36E boobs to prevent her getting 2 black eyes along with her trainers and watch her vanish in to the distance and direction of the cycle path we went on to Tina & Rob's house. The next night I told Amy I had to see a old mate of mine to help him out with his car so I wouldn't be back till late, I parked up on a nearby trading estate after work made my way to a picnic area in the wood just off the cycle path it gave me enough of a view to see anybody coming along the path around the time Amy went off for her run. I had waited about 10-15 minutes and I could hear someone running along , so I crept behind a big Rhododendron bush to see Amy running and stop at a wooden 5 bar gate a bit further along but I still had a good view from where I was, when I heard some noise and I saw Rob cycle into view , he stopped went over to Amy put his bike down , grabbed her and I watched them kissing , holding each other. I was interested to see what else would happen now, it was still a lovely warm evening and Rob just pulled Amy's vest off over her head , undone her bra, rubbed his hands over her boobs and bent to suck and bite on her nipples , Amy's mouth opened wide as she gasped for air and grabbed his head pulling it tight to her boobs. Amy soon said get your cock out Rob ! I want to suck it !, Rob only had a t -shirt and shorts on with his trainers , he pushed his shorts down to his ankles stepped out of them as Amy knelt down on the forest bark to smile up at him as she began to lick an suck his cock , it was his turn to gasp now as Amy took his cock into her mouth I stood remembering the times that Amy had done that to me in various woods and forests we had been in , in the past and guessed the result would be the same , except this time it would be Rob fucking my Wife on the Forest floor or against the gate. It wasn't very long till Rob's cock was stood big and proudly in front of him , I could see Amy's hot body glistening in the light as she gave it a few long sucks before , looking up at Rob and asking how do you want to do it tonight ! He stood his cock twitched as he told Amy to stand on the bottom rung of the gate and push her bum out , she obeyed and Rob walked over an began to bite, kiss and lick her fab arse as his fingers teased her clit and found their way inside her pussy, she was begging him to fuck her,, as he stood up there was a string of precum hanging from the tip of his cock. I watched him spread her cheeks wide with his hands, her legs parted waiting for his cock , but he teased her by pulling on her nipples , Amy was near to tears now begging him to just do it , Oh Fuck me Please, Dear God !. Then he smiled as he pressed the fat head of his cock against her wet pussy, Rob then put his arms over Amy's shoulders pulling on the gate to make it move back towards him a couple of inches as it was held by a chain and padlock and his cock sunk its way inside my wife ( it made me think of Tina saying ,Amy was a dirty slut after all ) Amy groaned Oh you big cocked bastard at him , please just Fuck me hard ! , I need you now ! Well he didn't hold back now and was soon buried balls deep inside my Slut of a Wife before pulling back out ,ready to ram it back in and that gate certainly began to squeak and groan and clatter with the noise of the hinges and that chain . Then from my viewpoint behind the bush , I could see movement on the cycle path and there were a pair of 50's couples stopped off the saddle stood watching Rob fucking my Wife , they were talking to each other as they watched for a couple or so minutes before riding off. I was now left as the sole spectator to watch Rob hammering his cock into my Wife hearing Amy saying oh please cum now!, I want to cum again and Rob was not one to disappoint as he grunted as he lifted Amy's feet off the gate as he held her on his cock as he came inside my Wife's now soaking pussy as she gets very wet when excited. He then lowered her down on to the Forest floor and Amy sunk on to her knees on all fours ,I think she was just exhausted and I had a view of her bum facing me , her pussy was left gaping and dripping with Rob's cum shot, as I looked at Rob he looked as if he had given her his all as he was bent forward his hands on his knees, while he looked and smiled at Amy who I assumed was smiling back at him as her face was out of my view now. Rob helped Amy up and I watched as they kissed again with some passion, his hands gripping her lovely bum and he could not resist running his fingers between her wet pussy lips and I watched as he gave them to Amy to suck clean. Amy went to grab her clothes as did Rob as I watched them dress and I saw Amy wipe her pussy with some tissue she had with her , as they kissed again and said their goodbyes , I noticed Amy had dropped the tissue as she turned to leave , I stood there long enough to see them both vanish in to the distance and made my way over to pick the tissue up and I ran it under my nose to smell the aroma of their combined juices, before making my way back to my car and heading home to meet Amy coming out of the shower where she kissed me and I thought I could also taste and smell their cum on her tongue and lips. We got into bed later and I cuddled up to Amy and slipped my cock inside my Wife's wet an warm pussy from behind it was certainly very wet as I held her at arms length I looked down her back to her arse under the light to see a bite mark on her shoulder and scratches on her back and bum as I rammed my cock into her as Amy again said she was coming for the last time for that evening , as I deposited my load inside my Dirty Slut !!!!!