Another conversation around that event, but with a whole lot more people involved in this one. No sex, so no surprise there. There isn’t usually much sex going on during those types of conversations.

I braced myself for what was to come. I’d seen looks of sympathy and smirking grins already, and knew it was going to happen, but it didn’t matter.

I looked at the door for what was probably the last time, took a deep breath and settled my face into a neutral expression. Then I opened it and entered.

Thirty-six faces turned to stare at me.

“Settle down,” I said. “Jackson, go and sit in your own seat and leave Cummings alone. He’s not your play toy.”

Reluctantly, the rat-faced teenager left off tormenting the overweight boy that he’d targeted for the past month. Stanley Jackson was a bully, and quite honestly, a mean little fuck. I knew about the nightmare that was his home situation – the drinking, the drugs and the violence – and I could understand how any kid would turn to the dark side in those circumstances, just to get through the day without having a complete breakdown. While I could understand it, I still couldn’t accept his bullying others in order to make himself feel good. The problem that I and every other teacher faced in this situation was how to punish bad behaviour when that youngster would go home everyday to face so much worse than anything we could throw at him.

I picked up the register and clicked my pen.

“Alderly?”

“Present, sir.”

“Brown?”

“Present, sir.”

“Cummings?”

“Present, sir.”

I did the roll call, listening to the calls of ‘Present, sir!’ almost absent-mindedly, and at the end was a little surprised to find all my charges present, and if not correct, then at least not running riot. This was my first posting as a teacher, and it had taken me a little while to gain control over the pack of slathering monsters that comprised my current sixth form class. Two years later, I almost had them eating out of my hand.

As I finished congratulating myself, it started. There was a little noise that sounded like a strangled chicken.

“Cuck, cuck, cuck, cuck.”

It was coming from good old Stanley Jackson; of course it was. I was in a situation where he felt he could torment me and certainly wasn’t going to give up an opportunity like that. He was trying to make the sound without moving his lips, but was doing it badly and I could see his Adam’s apple bobbing up and down in his scrawny throat in time to the sound.

I sighed, stood up and moved to the front of my desk, perching my bum on it and looking around at the faces watching me. Well, apart from Karen Evans, who was once again trying to text on her phone without me seeing: trying, but not succeeding. She never did catch on that when she looked at her phone, it lit up her face, and so the phone grassed her up every time she did it by shining a spotlight on her.

“Karen, bring me your phone. You can have it back after class.”

Her pretty face lifted sadly. She knew the drill.

“Oh, sir. I was just...” She couldn’t come up with a lie quickly enough and trailed off.

I held out my hand and she reluctantly dragged herself up and brought it to me as if she faced execution.

Hands-free for probably the first time in a week, she turned and stomped back to her desk. I turned the phone over in my hands and the idea that I’d been turning over in my head since I got to school that morning took form and solidified. I put the phone down and looked at them.

“Put your books away,” I said, as the chicken noise started up again, while Jackson looked around with a big smile, as if searching for applause and approbation. I ignored it.

Surprise on many faces, they put their books back in their bags, or piled them up in a corner of the desk.

“Right, phones please. All of them, on my desk.”

There were protests and moans, but in the end I had them all laid out in a grid pattern on my desk according to where they sat in class. There was a gap.

“Linda, your phone!”

She looked wounded and almost frantically tried to deny she had it with her, but a look at my face showed her I wasn’t going to give in. Finally, she brought it forward and seemed to be trying to power it down as she walked between the desks. Her thumb must have slipped as the screen lit up as I took it from her. There was a picture of a naked man holding a hard dick on it. She blushed scarlet.

I carefully didn’t allow my expression to change. They were all legally adults, so it wasn’t my business. It wasn’t her boyfriend, however.

“Thank you, Linda. Despite lying to me about not having your phone – there won’t be any problems about this.” I tried to make my meaning clear by the tone of my voice, and powered the phone off in front of her.

She understood, and looked so relieved it was as if she’d just had an instant shower. I saw her eyes moisten.

“Thank you, sir.” It was an academy school – and in this school the sir or ma’am was mandatory. In this case, it was heartfelt.

I nodded. “Go sit down.”

I put the phone down in its place on my grid, completing the six-by-six pattern, and turned back to the class.

“Okay, now the reason I made you hand your phones in was because I didn’t want any surreptitious recordings of this lesson. You all have to be aware of how things can get out of hand when things hit the net, and I don’t want that to happen.

“I know you’ve all heard the rumours about what has happened between me and my wife, so I’m going to tell you about it, which will hopefully stop the wilder rumours, and I really hope you’ll learn something you can use in your own lives. I’ll be as honest as you want, and when I’m finished, you can ask whatever questions you like – about anything. So you can stop making those stupid noises, Jackson. Yes, I know it’s you. Your throat moves. Try watching ventriloquists, that’s how you can tell.

“But let’s start with that. Jackson has been calling me a cuck since class began. Everyone know what a cuck is? Hands up those who aren’t sure – nobody needs to feel dumb if they don’t. It’s not a word that you see every day.

“A cuck is short for cuckold. Its origins trace back to the French word cucu – from which we get our word cuckoo. Because that bird lays its eggs in the nests of other birds, for them to feed, protect and raise as best they can, it came to mean a man whose wife is unfaithful – thus raising other men’s children as his own.

“Most of you have met or at least seen my wife Emily, at school functions and sports days, and most of you – probably all of you – have heard that she had an affair and that all was revealed in a rather noisy altercation on Friday. She effectively made me a cuckold. I’m being honest with you here, so I’ll go into as much detail as you wish, although I’d rather keep the really intimate details to myself. But, I offered, so if you ask, I’ll tell. That’s a fair warning though; you’re all legally adults, so at least the head can’t fire me for corrupting children.

“And if any of you don’t feel you want to hear what I’m about to say, just put your hand up and I’ll give you a note and you can spend this class in the library, okay? Who wants a note?”

I was pretty sure of my wolf pack, and sure enough, not a hand twitched. Children – and despite being in their late teens, each still had a fading part of them that thought like children – are inveterately curious, especially about things they feel that adults are hiding from them. Here I was offering them a free pass to all the information they wanted.

A hand went up.

“Tracy? You want a note?” That really surprised me. Tracy Smithy – or TySy as she insisted her friends call her – was the complete gossip. I was pretty sure that if the office handed her a memo instead of printing out a copy for each pupil, it would get to a lot more people a whole lot faster, and they’d pay a lot more attention to it.

“Oh no, sir!” she said. “I just wondered what Mrs. Marsden did exactly.”

Well, at least the pain I felt at her question was just an echo of how I had felt when I opened the door and saw them. I couldn’t have survived if that emotion had continued to run at its initial white-hot temperature.

I took a deep breath. “Emily met up with an old lover of hers from the time before we were married. She didn’t tell me about that meeting or any of the ones that followed. They became intimate and would spend several hours together each week at a hotel on the coast.”

“Cuck, cuck, cu ... awk!”

Leonard Alderly had leaned over and squeezed Jackson’s throat, one-handed. “Shut the fuck up!”

Leonard was a tall, thin boy with lanky brown hair and was slightly bucktoothed. He was quiet and fairly studious, preferring to spend time online with his friends than out on the street corners where most of them hung out. Tellingly, he lived with his mother in a one-parent family. Something had resonated within for him to react so intensely. I wondered about the one-parent side of his circumstances.

“Leonard,” I said equanimously. “Please don’t kill him. Think of all the paperwork I’d have to do.”

He gave a last squeeze and then pushed Jackson away, giving him a filthy look. I guessed that he’d taken enough of the little rat’s torment in the past and his blatant attempt to torment me had finally caused him to boil over. That look morphed into one of surprised, blushing pleasure when Jenny Radcliff leaned over to squeeze his arm and give him a look of intense approval. That little gesture might turn into something a whole lot more meaningful if my experience of teaching teenagers was anything to go by. Cummings gave him a double thumbs-up with a wide grin on his round, pleasant face.

“How did you find out, sir?” asked Cynthia – a dark-haired girl with sharp features, but managing them well. I guessed she had a mother or older sisters who really knew how to handle make-up.

“Mileage,” I said. “The hotel wasn’t far away, but it was a whole lot further than a trip to Emily’s office or to the shops. I keep a note of petrol consumption and mileage for both our cars, as my dad had shown me that you could spot engine problems before they got too big by keeping track of fuel economy. All it needed was a little maths and statistics, and I realised that she was travelling out of town a couple of times a week. I followed her and found they were visiting a cheap hotel.”

“I would have used a PI,” stated Weeks – a boy with a never-ending repertoire of short-term enthusiasms.

“Do you know how expensive they are to hire?” I asked. “You do know I’m a teacher with a teacher’s salary, don’t you? You’ve been watching too much Hollywood.”

At least I was a teacher for the present moment.

He grinned and made the shape of a gun with his fingers at me. I couldn’t help grinning back.

“So have you two broken up, sir?” This one came from Agnetha, an overweight blond girl who sat in a back corner in every class she’d ever attended – although attendance was never a certainty in her case. I knew that Social Services had taken a look at her situation a couple of times, but never found anything serious enough to start alarm bells ringing. “I mean, it’s just ... fucking, isn’t it? It’s not very important.”

I could see on her face that she’d tried to find a euphemism but given up. A nervous titter ran through the class. I thought that, with that attitude to sex at her age, Social Services may have missed something important.

“You know what, Agnetha – you’re right. It was just fucking.” That silenced the titters and seemed to raise this conversation in their minds from a lecture by yet another boring teacher, to something that might treat them as the adults they were desperate to be. “And I guess if Emily was careful about using condoms so that she never got pregnant and really went cuckoo on me, I suppose it never took anything away from me. So why give it any importance?

“I mean, it’s not as if any of the equipment involved wears out with use, for either the man or the woman. It’s not as if the man has to use a sharpener to keep a point on his penis, or that a woman’s vagina wears away until it’s the size of a cathedral. So why all the shouting and screaming and tears and...”

Oh god, I didn’t want to remember that evening anymore; the photographs I’d taken of them getting out of the car and going into the hotel, with the time stamps circled in the lower corner; the ones of them kissing at the door to the room; the ones I’d taken inside the room when they were going at it like stray dogs in an alley.

The door to the hotel room had been one which closed and locked itself, something prevented by quickly nipping forward from the shadows and slipping a piece of cardboard between door and jamb as it slowly closed behind them. Then came the wait in the corridor, trying to look as if I was hanging around to meet someone by constantly glancing at my watch. And finally, desolately hearing that very specific noise she always made when a cock first plumbed her depths at the start of a session, which told me I could at last go in, get the evidence I needed and get the fuck away from that place. I had vowed never to go to that town ever again, never mind that cock-pit of a hotel.

“ ... and the drama?” I finished. “It’s the emotion, the trust, the respect, the belief that you are both on the same team, working together towards the same thing – a good marriage. When you get married, you promise each other various things. I know people make up their own vows, but they usually include an implicit or explicit promise of sexual exclusivity. And for homework I want a paragraph on the specific difference in all their forms between those two words; implicit and explicit. While you’re at it, you can also give me a paragraph on assume and presume.”

They smiled. A paragraph or two was something they could do in five minutes with Google. It would be good practice for their English finals.

“I also want a two page essay,” I continued speaking over their disappointed groans. “On the history, the legalities, and the meanings of a marriage contract – past and present. It’s something you need to know in a lot more detail than you might think. Always operate from a position of strength, and knowledge is strength. Knowledge is power!

“That’s why we go to school. That’s why you’re all here, wishing I’d forgotten about giving out homework assignments.”

They gave varying degrees of smiles at that weak little joke.

“Okay, in reality your parents actually send you to school just to get you out of their hair for a while so they can do adulty things and get some peace and quiet for a while, but for you – you’re here to learn how to grab power over your lives. Now repeat after me: ‘Ladies and Gentlemen, I call this meeting to order!’”

Puzzled but willing to go with me to some extent, they chorused those nine words.

“Now say: ‘Do you want fries or potato wedges with those nuggets?’”

There were giggles as they did so. Jackson didn’t participate, which was a pity. He was one of the brightest boys but had locked his future into helping his brother sell weed from the boot of a crappy broken down car. I’d taken him aside at one point and asked if he had considered the economic future of that career. He’d sneered.

“I’ll be making more money in a month than you’ll make in a year.”

“And when Britain joins the US in legalising marijuana? Who’s going to want to shop from you in a back alley, when there’ll be stores up and down the high street, offering a much wider range at fixed prices, and with no supply problems. Nice, bright, shiny shops – while you’re scraping a living out of an alley alongside their dustbins. You’ll be out of business in a month. And don’t even think about going on to harder stuff. With all those coppers freed up from having to chase the smokers, they’ll be coming down with an iron fist on the real drug problem. You’re already extinct. You just don’t know it yet.”

His answer was predictable, I suppose. “Yeah? And you’re a bell-end!”

I posed the next question to the class, needing them to get this message more than any knowledge they might pick up in a defined lesson. “Now think carefully. Which of those two sentences made you feel better, more important, more empowered?”

Most felt that the former felt better.

“This is the time that you decide which of those two things you want to have in your future. It’s an opportunity, don’t piss it away.”

The laughter at that mildest of swear words was louder than it should be. They were still getting used to the fact that they were on a par with me in this conversation.

“So it’s not about the sex, but the emotion?” Agnetha dragged me back to the matter at hand.

“Actually, it’s both,” I replied. “Because, if you married for love – rather than convenience or arrangement – then both are intertwined so closely it’s impossible to separate the two. Let me put it another way. My Granddad always told me there was only one philosophy that you should live by: always keep a promise, and try not to be a dick.”

The word dick got a laugh of course. This was a classroom and I was a teacher, and I shouldn’t be using that language, but it was just one lesson.

“Think about that. Always keep a promise. If you make a promise then keep it – not always easy, I know. But the thing that’s not said, is that if you can’t keep a promise, then don’t make it in the first place. If you don’t mean to remain faithful to your partner in a marriage, or even in a relationship – then don’t promise to do so. Have the courage of your convictions! If you don’t think you can be exclusive then don’t promise to be so – and take the consequences of that.

“But sir,” protested Melanie, who was easily the prettiest girl at the school, but who kept the boys at bay, and was thus branded a lesbian. “People live a lot longer than they used to, and marriages therefore mean having to remain faithful for a lot longer. People change over time and they fall in and out of love.”

“That doesn’t change anything,” I reasoned. “Of course people change, and some do fall in love with other people – I recognise that, and so does the law. That’s what divorce is for. So if you find you’ve made a promise but are no longer able to keep it, then find the courage to go with your feelings and withdraw your promise before you break it. Sure it would have broken my heart if Emily had announced that she no longer loved me, or was just too horny for somebody else to remain faithful, and the divorce would have hurt me enormously. But it would have hurt a whole lot less, a whole world less, than her going behind my back and sneaking off to have an affair.”

“Are you going to divorce her, sir?” asked Melanie, her green eyes seeming very bright in the afternoon sun.

“What do you think?”

“Drop her like an anvil, sir!”

“He could forgive her,” said Isobel with a shrug, a thoughtful expression twisting her Mediterranean features slightly. “It’s an option he hasn’t mentioned.”

Melanie’s long golden-red ponytail swung sharply as she turned to her classmate. “Forgiveness should be for a mistake. Not a deliberate action!”

“People make mistakes all the time,” responded Isobel, warming to the defence of her statement.

“Once! They make a mistake once! The expectation of a different result from a precisely repeated action is not only meaningless, it’s stupid! If you keep doing the same thing over and over, it’s not a mistake, it’s deliberate.”

I had to smile approvingly at Melanie, as she’d repeated word-for-word what I had tried to teach them on that point in revising for the chemistry paper.

“A quickie while drunk is one thing,” she continued hotly. “A planned, ongoing affair is completely different. No mistake there!”

“Still, if Mr Marsden loves her, then he should forgive her, for his own sake.” I think Isobel was a hopeless romantic at heart.

“There are two fields of thought about forgiveness,” I pointed out, trying to ignore Alicia’s actions which I couldn’t help seeing out of the corner of my eye. The little blond cheerleader always sat in the front row in my classes and had the alarming habit of shuffling her butt forward in her seat and then slowly opening and closing her legs, which forced her skirt up and gave me full view of her panties and the shape of the camel toe they cupped. I don’t know whether she was trying to get something started between us – which was never going to happen; whether she just wanted to try and throw me off my stride in the lesson; or whether it was something she did everywhere when she was bored. I’m pretty sure I could have described in detail every pair of knickers she possessed, she did it so often. It always got a reaction – a twinge in my loins.

“Two streams of thought,” I began again. “One is that forgiveness teaches only that the guilty party can expect to get away with repeating the deed in the future, and the other is that it should only be offered for true repentance.”