Like many significant things in life, my downward spiral into adultery was gradual and the first steps were done to maintain the sexual quality of my marriage. I'm Sarah married 13 years to Ian, both in out late 30s. We met when I worked in our small city. Ian is a financial advisor. He's slim, fit, polite, reserved, conservative, well educated and dressed, socially conscious, and urbane when necessary; but no one would call him passionate, neither in his views and opinions nor in bed. In the early years, I liked very much when he consistently showed me courtesy and consideration during sex, with what he thought I wanted foremost in his mind. We had what I call 'comfortable' sex: missionary position with him making love to me with my satisfaction uppermost in his mind. The only energetic portion being when at the end he needed to drive himself to climax. At first, I enjoyed his consideration since I had come to him from a sexually abusive relationship, but I soon discovered the few orgasms I had had with my previous lover were entirely absent with Ian. I didn't know about the pleasures of rear entry and Ian didn't like much woman on top, so when I would reach down between us during missionary to rub myself to an orgasm he told in a mild way that it made him feel inadequate. So I began faking orgasms to make him feel better about himself. Since he liked having sex at night in bed just before sleep, I would slip out afterward and bring myself off with my fingers sat on the sofa in our lounge downstairs. I found that faking it with him actually made sex more pleasurable for me since in order to do it well a woman must begin early on by being more physically energetic along the way, which actually enhanced the sex for me, although not enough to come except for a few times. So, I was happy with the result and Ian was happy that I was seemingly coming with him most times, and I still was having orgasm later with my fingers. The problem came when my girlfriends would talk about orgasmic sex with their husbands and about watching well hung black studs on internet porn taking wives to heights of pleasure by violently shagging their brains out. I began watching that action on internet porn in amazement and soon was fantasizing that such a man was in me when Ian made love to me. Those thoughts made me even more energetic during sex and I actually came more frequently with Ian, but still only occasionally. I wondered how those petite wives in the porn could take those huge male members inside, so I bought a well sized black dildo and began using it during my time on the sofa at night after sex with Ian. I gradually became used to the dildo's size and began using it also in daytime when Ian was at work. That led to gradual disappointment with Ian's size when making love to me so I needed to use it that much more frequently - a vicious cycle. Then the trigger event occurred. I had retained my membership in the fitness centre located a few blocks between where Ian works and I used to work until a stopped a few years ago. I go there on Monday, Wednesday, and Friday mornings and then to lunch with Ian at least one of those days. That's when I became acquainted with Greg, one of the new instructors. He is my age, built like an Adonis, and seriously flirty. I must give off that look, manner, or whatever a woman who is sexually available gives off that men instantly recognize; because from the moment we met about two years ago, Greg had tried to pull me, somehow knowing I would not take offence even though I refused him. It took him almost six months until I finally agreed to meet him for coffee at 3 the one day a week, Wednesday, he got off early. He took me to an out of the way coffee shop near where he lived not far away and, one thing leading to another, I soon found me at his flat. He showed none of Ian's characteristics toward having sex with me. He wasn't abusive and did nothing I didn't like, unlike my lover previous to Ian. He simply 'took' me sexually like a dominant male, knowing exactly how to handle me and never asking, just taking. And I loved it. Once inside his flat, he pulled me into his arms, said he had been waiting six months to have me, and kissed me with passion. Of course, by that time I was hot and ready, having been thinking about him that way those six months, and unconsciously making myself randy all through my workout session and the coffee knowing I would finally let him take me to his bed. I kissed him back passionately and we sucked each other's tongues and possessed each other's mouth just like in porn. By the time, as we kissed, when he slid his hand up between my thighs beneath my skirt and rubbed my pussy through my panties, I was so hot for him. His fingers found my heat and I moaned loudly as he fingered my clit. A few seconds later, he pushed his fingers through the leg opening and into my groin with his fingertips probing my wet furrow and rubbing my clit to engorgement. I was so hot that took only a few seconds. He then pushed two thick fingers inside me. He murmured I was already wet enough and then fingered me to an orgasm in only a minute or so. My body shuddered, my hips jerked against his hand, and I cried out. When I was finished, he withdrew his hand, picked me up, and took me to his bed, depositing me on my back facing him with my legs in the air and my bum right on the edge of the mattress. He quickly dropped his trousers and pants to mid thigh and then swiftly pulled my skirt and panties together from under my bum and halfway up my legs which were still straight in the air. His manhood was rock hard and looked huge, about the size of my black dildo. I was so glad I had gotten my pussy used to that size beforehand. Holding my legs up with one hand, he shoved the fingers of his other hand into my pussy and fingered me. Once he had the lips peeking out from between my closed thighs, he pushed the knob end of his manhood between them getting about two inches inside. Seeing the surprised reaction to his initial penetration on my face, he quickly asked if I could take it or did he have to go slow. I immediately told him to push in all the way, that I needed him in me. He smiled a conspiratorial smile that conveyed 'I knew you were a slag for me,' and pushed all the way up me with just two shoves. God, it felt fabulous finally being penetrated by a BBC. I snapped my head back as I loudly grunted with pleasure 'Oh, God, yes ... yes! ... YES!!' I needed to be taken right then hard and fast and deep; and that's what he did. There I was on my back at the edge of his bed fully clothed but with my skirt and panties up around the knees of my legs held straight in the air by my seducer, with this huge cock up my pussy all the way, doing me hard. He was pumping into me at a furious pace and going deep, really deep, and hard and fast. At penetration I was probably already half way there, and his rapid thrusting quickly pushed me the rest of the way. I came quickly wailing and crying out and twisting my body as an intense orgasm rolled over me like a tidal wave. I almost screamed out the 15 or 20 seconds of intense pleasure that overwhelmed me, a pleasure I had previously experienced only with my black dildo. And now I was in the throes of pleasure so earth shattering I never wanted it to end. But that was only the beginning. When my crying and yelping ceased, he pulled my skirt and panties up off my legs, let my feet flop onto the floor, and quickly pulled me up off the bed as he brusquely told me to finish getting undressed. He stared with lust all over his face at the rest of my body being revealed as he quickly got rid of his clothing. I had never felt so wanted, and wanton, in my life. I was about to allow a man other than my husband f--k me; and I couldn't wait for it to happen. My marriage vows went out the window, replaced by my own lust. Greg stood there naked before me with his thick 8 inch cock curved upward looking menacing, covered with my fluids. I sensed what he wanted so I slid to my knees onto the floor before him and grabbed for his cock. I wrapped both hands around it, one above the other, as I measured its length. The knob was above both my hands which made it about 8 inches long, and my fingers wrapped around it told me it was about the same thickness as my black dildo, which explained why his penetration went so well - I was already used to his size from using the dildo. I sucked and slurped and licked his cock to my heart's content, and felt like a slag doing it. He soon stopped me and told me to get on the bed on my hands and knees facing away from him with my knees right at the edge of the mattress. I was thrilled he was going to shag me from the rear. My insides went hot at the thought. When I was in place, he moved in between my lower legs hanging over the edge of the bed, and I felt him guide his cock to my entrance and push just the knob end between my waiting pussy lips. He asked if I was ready and when I moaned 'yes' he asked if I wanted it hard and fast. When I again moaned 'yes', he shoved it up my pussy with a single violent thrust that moved me about a foot forward, but I was swollen and sodden from his prior shagging, so it didn't hurt, it just surprised me. In reaction, I grunted loudly, and then pushed my hips back, impaling myself on that last fraction of an inch of his cock. I moaned, and then moaned again when he withdrew it almost all the way and quickly shoved it all the way back in. He did that again, and again, and then again, each time quicker between thrusts. And so we were off on rapid, deep, hard, and violent shag. And I was delighted. This was what I was missing in my marriage - hard shagging by a BBC. He did me for just a minute or two before I screamed out my second orgasm. He slow shagged me through it, and then speeded up again. I came in maybe another minute or so. He then repeated the slow shagging and then the subsequent violent shagging to give me a third orgasm. And this went on for four more orgasms. During the last one he came with me, spunking me with a bucketful of hot cum that was so much it immediately began running out and down the inside of my thighs from around his still thrusting cock. I was in heaven. When I recovered, with his still mainly hard cock stroking my pussy, he rolled us over so he was on his back under me and my hips were straddling his waist. He had me lift up and impale myself on his cock, and we did it with me on top. His cock soon regained a full erection. I rolled my hips on it as I pushed forward and back, which kept his cock in firm contact with my clit. It took a while since my clit was oversensitive from my seven orgasms, but some minutes later I came with shouts of joy. He helped it along by thrusting his cock up me as much as he could from that restricted position of his hips. When finished, I collapsed forward onto him and he slowly shagged me for a while. I kissed him several times with gratitude until our kisses heated up and became passionate once again. He then flipped me onto by back and then did me missionary for only God knows how long. I came three more times, and by then I think I was out of it. All I know from then on was it was over two hours since I had stepped into his flat until I finally left. I arrived home only minutes before Ian and when I looked at myself in the mirror after using the toilet; I looked like a slag after being with a dozen men. My hair was a mess, make-up totally destroyed, eyes sunken with exhaustion, and a general air of being ridden hard. I was able to repair to a barely satisfactory state when Ian walked into the lounge. I rushed down to meet him and he immediately asked what was wrong. I said I was feeling ill after my Wednesday workout and needed to get to sleep (little did he realize I meant being shagged and not exercising). Thinking I was ill kept him from attempting sex that night, which was a blessing since my pussy was so sore from my 'workout' it would have been painful to take even Ian's smaller cock. The next Wednesday Greg got off at 2 and I was in his bed for almost three hours. I was insatiable and came too many times to count, and Greg came in me four times. Since then, I've been in Greg's bed once a week getting my kind of violent sex. My sex life with Ian has not changed. He is happy not knowing I'm faking it with him, and I'm happy getting unbelievable sex from Greg. And Greg seems happy with sex with me; so all good!