Keith and Karen had been hard at it for over an hour now, and showing no sign of exhaustion, as a married couple shouldn’t who were so very much in love with each other. But more than that, thought Keith, as his pelvic thrusts pushed his erect penis in and out and in and out of Karen’s muscular vaginal grip, it was practice and exercise that made their physical love so successful. After all, if you were going to do something, and to do it as regularly as he and his wife did, after all their years together, then it was only possible if you worked at it.

Keith swivelled round, so that one of Karen’s legs was behind him and the other hooked out in front, her hands clutching the sheets that had mostly been torn off the futon and her teeth biting into the pillow. He held her buttocks up by his strong hands, her weight supported easily by his powerful arms, built up as a result of many hours in the gym, pumping with the same relentless rhythm he now applied to his coital thrusts. He could see the whole of his wife from this angle. And wasn’t he a lucky man! Karen was a real catch. The other teachers could just stare at them with envy whenever the couple sauntered together into the staff room.

Being a sports teacher, Keith had the advantage that keeping himself fit was part of his profession, but Karen, well poor Karen, had to keep herself fit in her spare time. But she was as dedicated to the body beautiful as Keith, and she did a damned good job at it. The trimness and athleticism of her waist, the tightness of her abs, the strength in her limbs, and that vaginal clasp with which she sucked out the life of Keith’s prick and simultaneously massaged life into it. The ripple of her shoulder, those strong biceps, the muscles in her thighs that could wrap around Keith’s tight, washboard-stomached waist and support her body by just the power in her legs. And the feats of athleticism, the variety of sexual attitudes, the choice of sexual positions, all available only to those who were the most vigorous, and denied those who lacked Keith’s and Karen’s physical fitness.

Sometimes, Keith felt sorry for Karen, stuck in the classroom all day, teaching French and Spanish and German (such a polyglot his wife!) while he could exercise and keep trim in the gym and on the playing field. And, though he didn’t want to divulge this to his wife, enjoy the spectacle of the trim physical form of his female students. He’d often thought that if it wasn’t for Karen, he’d be tempted by so much willing teenage flesh. But what lover could offer him the rewards that Karen could? What lover could have the energy to keep up with him? he wondered as he pounded away at his wife’s oozing gash

But all things have to come to an end. And so too did the lovemaking session they’d began so soon after they’d got home from work. There were papers to mark, food to prepare and besides Keith wanted an hour’s cycle ride before dusk to keep his upper thighs and calves in good working order. The two of them collapsed in a heap on the hard futon, a dribble of semen trickling out of Karen’s vagina and down her thighs, Keith letting his wife’s head rest on his shoulder while he idly stroked the tight, hard nipples that crowned her rather small to average sized breasts: almost the only part of his wife’s body for which a superlative term was not appropriate.

“So, what is the new intake like, dear?” Karen asked her husband.

“Nothing special,” Keith grunted, although he was secretly taken by many of the girl students, but not he knew for the right reasons. That Amelia… well! best that he not share his fantasies with his wife. “None of them are Olympics material. Put it that way! How about you? What are this year’s would-be linguists like?”

“The usual. The usual,” nodded Karen. “There’s one quite bright girl though. I think she’ll go far. But you’d hate her.”

“Hate her?” asked an alarmed Keith. Did Karen suspect his lust for students? “Why would I hate her?”

“Well, to say she’s not Olympics material would be a gross understatement. She is really really fat!”

“Fat! How horrible!” Keith said with genuine disgust. If there was one thing he couldn’t abide was obesity. How could people get themselves so out of shape? Surely, it was worth making that extra effort to combat all those surplus pounds of useless lard. “She must be the laughing stock of the class.”

“Well, not quite,” Karen admitted. “She might be plump, but she’s relatively popular. And anyway she’s not fat in a horrible kind of flabby way…”

“What other kind is there?”

“I don’t know,” Karen admitted. “But her size doesn’t look too bad on her. It’s strange really. She’s got a nice face, big friendly cheeks and her eyes sparkle in a really attractive kind of way.”

“But if she’s just a bowl of fat, she must look pretty ghastly otherwise,” Keith asserted.

“You’d think so, wouldn’t you?” said Karen thoughtfully. “And she does have an enormous bosom. And that stomach… I mean she doesn’t go for outfits that deliberately show off the stomach, but it swells out anyway. But her skin’s a nice kind of ivory, her black hair’s healthy and well-trimmed and she carries herself remarkably gracefully for such a large girl.”

“Pah!” snorted Keith. “I just don’t see how gross and grace can possibly come together. It’s like an antonym, isn’t it? Gross and grace. Fat and fit. Hefty and healthy.”

Karen laughed. “I guess you’re right. But you don’t need to worry about her. I don’t think she’s very likely to do sports as an option.”

As Keith jumped onto his bike to climb up the nearby Caffrey Hill, a strenuous three-in-one at its steepest, his mind moved well away from Karen’s students, and returned once more to his wife. They were so lucky. She to have him and, of course, he to have her. The two of them were the perfect couple. The zenith of creation. That was what it was all about. Okay! It had come as a bit of a shock when they discovered that his sperm count was way below what it ought to be and that the only way they could have kids was if they adopted. But posterity’s loss was their gain. His genes might not be passed onto the next generation, but at least by not getting pregnant, Karen could retain that glorious figure of hers for that many extra years to come.

However, the subject of Karen’s plump student, Fiona (what an effete name!), came up again, and again, in their conversations. She was such a very bright girl, Karen insisted. She had an almost intuitive grasp of syntax and semantics in any language. Karen had never met a student with such a keen understanding of the subjunctive, using it flawlessly and unprompted in her French lessons. And the complexity of German tense, mode and gender were as nothing to her. It was difficult to believe that Fiona had never learnt a foreign language before. In fact, her mother was just a housewife, although she’d been an actress when she was younger and her father just worked in an office as a systems analyst or database administrator or something. She was a natural!

Keith harrumphed. “Why do you keep going on about this girl?” he asked over the breakfast table. “Why not invite her round if you think so much of her? Give her extra tuition?”

If Keith thought his lightly meant sarcasm was going to close the subject, he was wrong. Karen’s face lit up. She ran a hand through her relatively short hair to the crop on her neck. “You know. That’s not a bad idea at all. Then I can coach her for the advanced studies. And perhaps I could teach her Turkish or Arabic. Languages not on the syllabus.”

“Turkish?” wondered Keith. “What bloody good is Turkish? I mean… I know you speak it, but you speak everything. But why teach Turkish?”

“I’d love to know what Fiona would make of the ablative,” remarked Karen indulgently.

It wasn’t that long until Keith first got to meet Fiona. He was home, energised after a school football match where his pupils had totally slaughtered the opposition. He was on a real high. And the best thing to seal a perfect day would be an hour or so of sexual intimacy with his favourite woman. His penis was already twitching in anticipation. He was almost already relishing that anal grip of hers that she was so expert in demonstrating.

But Karen was late, so Keith went down to the gym in the basement and worked out on a few weights while waiting. Eventually he heard Karen come in, her assured confident stride across the kitchen tiles, but there were also voices. Shit! No chance for sex just now. Who was the guest?

It was, of course, Fiona, as Keith established, when he’d towelled his face dry and made his way up to the kitchen. Christ! She was exactly as Karen had described her. If not worse! Those breasts were fucking enormous. And her stomach was positively obscene. And what was so sweet about such a puffy face, even if the folds of fat didn’t wholly obscure her bright light green eyes and that her smile was very broad and sparkling.

“I took your suggestion, Keith, to offer Fee some extra tuition. And she just leapt at the opportunity!”

“I did that!” said Fiona gaily. “Mrs King is such a good teacher.”

“Karen. Please,” laughed Keith’s wife with an enthusiasm he’d not seen in her since that orgasm she’d had which made her yell out loud enough it could probably have been heard on the next street. “And call my husband Keith.”

“Indeed,” the sports teacher said, proffering a firm handshake. Shit! How long was this girl going to stay? And what was this about calling her student ‘Fee’? “But I must get back to the gym. Stay in shape, you know. Can’t let myself get out of it, you know.”

If Keith’s barbed remark was meant to have an immediate effect, it clearly failed, as only grins followed him as he made his way back to the gym, where almost the first thing he did was put on a Ryan Adams CD to accompany his work-out. And he turned up the volume just a little louder than he normally did.

It was bedtime before Keith finally had sex with his wife and it really wasn’t as passionate or even as prolonged as Keith had hoped. He had no chance to enjoy her anal grip, and he’d almost not even released his own semen before Karen looked tired of it all. But as they turned over to go to bed, it was Fee that Karen was talking about. Fee this. Fee that. Fuck Fee! It wasn’t as if they were fucking lovers or anything.

Of course, even that changed, as Keith was to find out only a few months later.

Fiona became a frequent visitor. Two, three, and then four evenings a week for education gratis from his wife. Keith had no idea how the two of them could find so much to go over. He’d hated languages at school himself. He’d always been keener on getting out onto the playing field. And he’d put more emphasis on the school prizes he’d got on sports day than on any of his academic exam results.

And Keith noticed, as he really couldn’t help noticing, that the sex between the Karen and him was really not what it had been. It wasn’t a sudden change. Just little by little. First it didn’t last as long. And then it happened less frequently. In fact, Keith wasn’t sure it was even happening at all. Obstacles seemed to get in the way that never used to be a problem. Headaches, tiredness, over-work, slight chills: the excuses kept coming.

And then, one afternoon, he found he’d forgotten his kit and had to go home to pick it up. It was one thing, of course, for students to forget their kit. Indeed, Keith quite relished devising punishments for these skivers. Physical education was an essential part of everyone’s total education, and to neglect physical exercise was equally as bad as neglecting English or Maths. If only the examination boards could see it that way. But a teacher couldn’t commit the same crime, so he jumped into his two-litre Astra and drove home as fast as he could. However, what he didn’t expect to see was his wife’s Focus on the drive.

“Hey, Karen! What are you doing home?” he shouted, as he cheerfully entered the house. “Not sick I hope!”

There was no response. So Keith bound up the stairs and flung open the bedroom door expecting to see his wife in bed. Perhaps he could get her a cup of Lemon tea or some cough medicine. What he did see, however, was Karen hurriedly pulling on her slacks, her breasts still uncovered, and, a great deal slower than his wife, Fiona’s naked and oversize body rummaging around on the floor for a bra or a pair of knickers.

“Fucking hell, Karen! What the fuck’s going on here?” Keith exclaimed, knowing full well what it was. By no stretch of the imagination was it necessary to study German or even Turkish in the nude.

“I’m sorry! I’m really sorry!” Karen pleaded. “I just didn’t…”

“Just didn’t what?” Keith demanded. He stared at Fiona who was just covering an enormous breast, with its proportionately massive nipple. Her skin was very white. Like ivory. No sun had ever touched her skin. And so much of it! How could anyone not be just repelled by such a sight? He addressed Karen’s student with the barking authority he used on the sports field. “This isn’t the first time, is it? How long have you been defiling my wife?”

“Don’t call it ‘defiling’!” Karen insisted softly, while Fiona slowly raised her eyes from the floor where she’d been studiously avoiding Keith’s gaze and looked in his approximate direction.

“For ages now. Weeks, I think.”

“What the fuck!” Keith spluttered with rage, totally not sure what to do. Staying there would only make things worse. Anyway he had sports to go to. “Look. Just get out. And don’t fucking come back!”

With that he rushed down to the gym in the basement, picked up his kit and shot off to work, Dire Straits thumping out of his car stereo and helping to further cloud his confused thoughts. What was his wife doing? How had that fat, obese, gross, flabby, lump of lard managed to… managed to…? And how had his wife fallen for it? How stupid was she?

Things didn’t exactly get back to normal. After a long tearful argument, Karen agreed never to see Fiona again outside of the classroom and Keith accepted his wife’s apologies as reluctantly as he was able.

And then Keith thought things might go back to where they’d been before. Although the sex didn’t quite return. Okay. It did on the night of reconciliation. It was sort of expected really as the only way in which Karen could possibly convince Keith that she still loved him. But, somehow, the lovemaking was perfunctory and acted more as a way for Keith to shed some of the animal aggression that he thought might otherwise explode into violence. And it was true, even though Keith never considered himself a ‘new man’ as such, that he honestly would never, could never, hit his wife.

And then, several weeks later, Karen made a confession. It was while they were out for a meal in a restaurant, Karen chewing on her vegetarian quiche and Keith munching through his pound of rare steak. The lights were low and it was only natural to keep one’s voice low as well. Keith looked across at Karen, the shadows cast by the dining table candle dancing around on her chin and cheeks.

“You’re still seeing her? After all you said!” he said aggressively but softly.

Karen lowered her head. The shadow of her face hid her eyes. She raised her head again, looked Keith directly in the face, her eyes carrying a kind of assertive defiance. She lifted a glass of red wine to her lips, sipped on it and frowned.

“I know it’s wrong of me, Keith. I know. And I still love you too. You know. Just not as much. Or really in exactly the same way. But she’s the one I really love. I just don’t really understand it. I’ve never felt the same way for a woman before. Or a man for that matter.”

“What! Even me? Even when we started going out together? When we used to fuck like rabbits? When we never thought we’d ever stop?”

Karen sighed. “Even you, Keith. But I haven’t loved anyone else as much as you. Fiona’s the only one. Even Pete, my boyfriend at school… You’re still the man I’ve most loved. Believe me!”

She stretched a hand out over the table, her salad forgotten, and clasped her husband’s hand in hers. She smiled at Keith as warmly as she could.

“How can you though?” wondered a defeated Keith. “She’s like a fucking hippopotamus!” He could see Karen wince with pain at the harshness of the comment. Well fuck her! She had to know what he thought. “And do you still…? You know…?”

Karen bit her upper lip. The upper incisors briefly glinted in the candlelight. She nodded her head slowly. And then judging that that wasn’t affirmation enough she confessed more: “Yes we do. I don’t know why. But I just have to. And she says she loves me. And I love her so much. And when we’re together… I mean, believe me, Keith, it’s real love. Real love. I just can’t describe it!”

Keith gazed at his half-eaten steak on a plate strewn with mange-touts, zucchini and parboiled potatoes. He just didn’t feel hungry any more. He raised his head, his hand still clasping Karen’s, and looked her straight in the eyes.

“What are we going to do about it, then?”

Keith loved Karen too much to lose her. And Karen still wanted Keith. He was, as she told him again and again, the only man in her life. If only that was all it took! But it wasn’t straight away that Keith became one corner of the unlikeliest menage á trois he could imagine. That took time. But when he accepted that the only way that he and Karen could stay together was by accepting Fiona’s continued presence, it was probably somewhere in his mind that things might evolve that way.

At first, Fiona remained just a visitor with Keith agreeing not to intervene when she and his wife made love together. Then she left her own home and moved in with Karen. After all, she was above the legal age and her parents were very understanding. There were three bedrooms in the King household. Previously two had been for guests. Now only one of them was reserved for guests.

Karen was very diplomatic. Although she insisted on sleeping with Fiona every day, it was with Fiona’s express permission, - indeed, Keith discovered, on Fiona’s actual prompting, - she also began having sex with Keith again. It was not an offer that Keith was likely to turn down after so many months in which the only sex he’d had was that in his mind when he thought about his more attractive, fit and lean students, and where each night he could hear the two female lovers making love (“Oh! Fee! Fee!” “Kaz! Kaz! Ka-a-a-zz!”).  In fact, he and his wife almost made love just like they used to do. Well the duration was much the same, although the intensity of passion was somehow compromised and it wasn’t quite the twice-daily exercise of their pre-Fiona love life.

And eventually it had to happen. Karen wanted to close the triangle. She no longer wanted to be the sole apex. At first, Keith was reluctant. And Fiona was very shy too. She’d never had sex with a man before. And the only person she’d ever made love to at all had been Karen.

Keith was soon off with his clothes, Karen already naked, while Fiona apprehensively removed her long dress and slid her knickers down the huge mass of her thighs. This was only the second time Keith had seen Fiona naked, although he’d got accustomed to seeing her in her dressing gown and pyjamas as they ate breakfast together and prepared for school. Yes. She was fat. Grossly so. You couldn’t see her vulva or any evidence she even had one under that mass of blubber. But her skin was so very white, and Keith had to acknowledge that her eyes and her smile shone in a very seductive way.

Keith had promised Karen that he’d be gentle. And so he was. Although it was almost as much a first for him as it was for Fiona. She’d never made love to a man before. He’d never before made love to a woman so outrageously out of shape. What had happened to his standards? And it wasn’t that easy to position his taut muscular slim body against her stomach and crotch in such a way to get the leverage he needed for his rhythmic thrusts. And even with Karen there to help, gently massaging and licking Fiona’s huge nipples and guiding Keith’s penis into position, it couldn’t be said that this first time was the most successful first time in which Keith had ever participated. And he’d had several of those, as befitted such an attractive man.

But as they slumped back on the futon, Karen licking up the semen from Fiona’s crotch, and Fiona idly stroking his penis, Keith knew for sure that this was just a first time. There’d be many more such times together. Whether it was how he’d wanted it to be, somehow he, Karen and Fiona just sort of suited each other. He had to admit that they kind of fit together.