This story contains a lot of Taboo sex and also Incest.
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I've been married to my wife Sue for 12 years, Sue is 33 and has a very good job in the financial world, that takes her all over the world at times and she has an older sister called Clair aged 34, there is only 13 months difference between them.
Clair is a very complex woman, she has two teenage children but not been in a long term relationship since the birth of her youngest 13 years ago. She has no shame and is very brazen, she has no filter and says what she thinks and isn't afraid to ask for anything she wants. Clair has a reputation as being easy and rumour has it she has had many one night stands.
Luckily for us we live over 200 miles away from her and apart from the odd phone call we hardly ever hear from her.
Clair is very pretty and a curvy girl and one thing she has going for her are her stunning 40D tits, she knows they are her best asset and uses them accordingly. She needs no excuse to get them out especially when she has had a drink or two.
We've all seen them plenty of times at family parties and bbq's. But I'm not complaining as they are amazing, she has the largest areoles I've ever seen and real hard nipples about half an inch long. One time at a bbq she got me alone and grabbed my crotch and said "show my your dick."
And since then on the odd occasion I see her she flirts with me and says "one day I'll get to see your dick."
One Thursday afternoon recently the doorbell rang, Sue went to answer it, "what the hell are you doing here?" Asked Sue.
"I need a break from those fucking kids of mine." Clair replied in her usual subtle way.
"You could have called in advance as I'm going away on Saturday for a few days."
"No problem, get the kettle on sis."
I was already in the kitchen as Sue and Clair walked in, "hi Paul, my case is in the car." She said as she hugged me while rubbing her thigh against my dick and pressing her tits against my chest.
"You haven't changed Clair." I said as I went and got her bags out of her car.
I put her bags in the spare room as Sue made the bed ready for Clair.
"What are we going to do?" I asked Sue.
"I don't know, can she stay here with you once I go away?"
"I suppose so."
After dinner we all sat chatting in the living room, "look Clair, as I'm going away on Saturday you'll have to stay with Paul, is that okay with you?"
"Yeah, if Paul don't mind, I just need time away from the kids, they're driving me crazy."
Clair went upstairs for a shower and to get changed while she was gone Sue asked me "are you sure you can cope with her? You know what a flirt she is and she's bound to come on to you."
"I'll be okay, don't worry." I assured her.
"Well just do what you gotta do."
I wasn't quite sure what Sue meant but just left it at that.
Clair came back downstairs in a dressing gown and we all sat talking once again.
From where I was sitting I could easily see in the front of Clair's dressing gown, I could see her huge cleavage and most of one of her tits. She knew I was looking and kept smiling at me.
Every time Sue left the room Clair put her hand inside her gown and stroked her tit while looking at me. "Do you want a feel Paul?" She asked.
"I'd love to Clair, and you know it, but Sue would kill me if she caught me."
She then pulled open her gown and revealed her amazing tits, they were as amazing as I'd remembered from the last time she flashed them to me a few years ago, she stroked them and pinched her nipples, my cock hardened in seconds and I was seriously tempted, but we heard Sue coming back and Clair covered herself up.
"It's just you and me from Saturday." Clair said with a naughty grin.
My mind was racing as I want to fuck her but I don't want to risk losing Sue over it. But my thought right now was just go for it, I was horny as hell and really wanted her.
Saturday morning arrived and Sue was busy getting ready to leave for the airport, Clair had only just got out of bed and I was helping Sue put her case in the car.
She pulled me into the bedroom, "I want a word with you, I know what Clair is like and she'll definitely come on to you when she gets a chance, I'm giving you my permission to do what you want with her, but I never want to know the dirty details." Said Sue.
I was stunned, not wanting to hurt her I replied "don't worry Sue, I won't do anything I shouldn't."
But secretly I knew what I was going to do especially now I had Sue's permission.
Clair and I waved Sue off, Clair waved with her left hand and she groped my arse with her right hand. I knew there would be fun starting soon.
"I'm starving, do you want breakfast?" Asked Clair.
"Yes, sounds good."
I made a hot drink while Clair made breakfast, then we sat down at the table to eat.
"Look Paul, let's clear the air right now, you know I've wanted you for years, and I think you want me too, if we keep it to ourselves we could have some fun while we've got the best chance ever, if I'm wrong just tell me now and I won't mention it again."
Clair obviously doesn't know I had the green light from Sue so I decided not to tell her. "Erm, I'm up for it, but it must always stay between us."
"I'm glad you agree, we are going to have loads of sex, and you are going to discover things about me you never imagined."
"Really, that sounds interesting." I replied.
As we sat eating breakfast the front of Clair's gown was completely open, I could see her big tits, she knew I was staring at them. "I can't wait to get those in my hands and mouth."
"From what Sue has told me many times you love eating pussy too."
"That's true, it's the best thing about sex, I could eat pussy all day every day."
"Well that's good because I love having my fanny eaten, has Sue ever told you anything about my fanny?"
"No, she's never mentioned it actually."
"Well I'll tell you more later, you'll see it soon enough but I want to explain something about it before you see it, touch it, lick it, taste it and fuck it."