It wasn’t until they had to paint the living room wall that they realised the Billionaire was a billionaire.

Both Luna and Shiv had been leaning their bicycles against the wall, and when the flat’s owner, a good friend, informed them he was coming back to repossess the place at the end of the month, they thought it would be courteous to repaint the scuffed surface before they left.

Since Shiv used the living room to teach, and the painting work was not finished, the Billionaire, when he arrived for his lesson – he was learning Led Zepplin’s ‘When The Levee Breaks’ – looked at the empty white surface and said, ‘I should get you something for that space.’

Pupils often brought wine, biscuits, oranges or flowers. But the next time the Billionaire came, his driver accompanied him with a large, framed and excitingly-dramatic photograph of Jimmy Page, signed by the photographer.

The Billionaire took it from the driver and handed it to Shiv. ‘This is for your wall, with gratitude and apologies for all the bum notes you’ve had to endure.’

Shiv thanked him, leaned the photograph against the wall and completed the lesson. When the Billionaire left, Shiv looked at the picture for a long time, moving it here and there. He texted the Billionaire his amazement, saying it was the loveliest thing he had owned.

Shiv and Luna were music teachers. Luna taught piano in schools around the area; Shiv mostly taught in the large flat they’d had for a low rent the past year, owned by a guitarist who was on tour with a musical. Shiv had had good fortune in recruiting a significant number of private pupils from nearby. If the students were young he went to their houses. Several parents – bankers, surgeons and executives – had also asked for lessons; one of them had recommended him to the man who became known as the Billionaire. The Billionaire had always loved the blues and R ‘n’ B, and needed someone to help him improve. He had been Shiv’s student for a couple of months, sometimes coming twice a week.

The flat which Luna and Shiv had been looking after had a garden which attracted birds, foxes, squirrels and local cats. Situated in a wealthy area, there was a park with a lake nearby and excellent transport. Shiv was impressed by size of the houses and the affluence of the families he visited, with their gardeners, cleaners, au pairs, other tutors and obligatory personal trainers.

Some of the parents of his pupils spoke to him abruptly if not dismissively, as if he were on a par with the ‘staff’. This was disconcerting: not only was his father a solicitor and his mother a doctor, he had always considered the devil’s music he taught to be classless. He complained to Luna that soon he’d be asked to use the side entrance.

That night Luna came home and saw the new picture leaning against the white wall. She too was knocked out by the portrait of Jimmy Page in his rock ‘n’ roll glory. They opened a bottle of wine, sat in front of the picture and discussed whether they should display it on the freshly painted wall, or wait until they’d found a new flat. If we find anywhere, and if there’s room for it, as Luna put it.

Luna stayed up late. Coming to bed, she woke up Shiv to say she had incredible news. She’d researched the photograph and found that not only was it an original – which they’d realised – but signed, it was worth at least £3,500. Maybe if they sold it, they could get more. Wasn’t that an idea? Didn’t they need the money?

Shiv wouldn’t sell it; the Billionaire would notice. Not only that, it would stir every student who came by. Anyway, he already adored it. He knew he’d miss it. It could be the start of a collection, a new hobby for them both, if they ever made any money.

She had been researching Arthur, Sam’s student, and had discovered something important: he was a billionaire. Even now in his mid-forties, he had invested in tech early on, bought property and restaurants, and was richer than many of the songwriters and singers they admired. What about that?

Sam was surprised but also irritated. What about it indeed? He was too lazy to research the people he taught and anyway, it was intrusive. If someone wanted to play ‘Back Door Man’ on the ukulele what did it matter what their day job was? The fees remained the same.

Luna asserted that people like them couldn’t afford to miss an opportunity; it would be stupid to be ‘left behind’. Shiv said he didn’t see what the opportunity was. She replied that that was typical of him. How, he asked. How is that typical? And of what? But if he didn’t get it already, she was too tired to explain.

The next time the Billionaire came for his lesson, Shiv noticed that Luna not only remained in the flat, she was listening if not watching from the kitchen. He even caught her head bobbing in the mirror.

Never do that, Shiv told her. It was distracting and he thought the Billionaire might have noticed. Do not spy. He’ll think we’re crazy and he won’t come back. Hey: what is it?

Come here.

She was naked in a moment, and they made love in front of the picture.

After, she remarked that the Billionaire wore no jewellery, his phone was old, his jeans and T-shirt ordinary. Also, he might appear polite and modest, and always did his homework, but he was, apparently, tough and demanding with his staff. There had been complaints and law suits. How brilliant and quite strange he must be to have achieved so much? Plus, she had found out a whole lot about his family. It was like Dynasty, and –

Shiv put his hand out. Stop. Stop there. Don’t go on. He didn’t want to hear anymore. It was pointless.

More importantly, she continued, she’d noticed the way the Billionaire leaned forward and listened to Shiv, his music mentor, with curiosity and his full attention. He must admire or possibly worship Shiv: his hands, his voice, his calm. Maybe he even loved him. Perhaps he wanted to sleep with him. Are you sure you don’t feel something for him? You can tell me. Don’t be inhibited. Touch me, and let’s explore it. Let’s go there.

Perhaps you do, Luna. Yes? And it is true, I do sometimes, love my students, Shiv agreed. They move me. They want something from me, and I want to help them. It’s an exchange, a kind of agape, or objective love. Not sexual at all. Not like that, no. It is a much deeper connection, that of people collaborating and sharing.

Whatever: Shiv had some kind of hold over him. It was there; it existed. That was something they could work with. There was demand and they were well positioned. Her best friend, a charity worker, already wanted to know if the Billionaire was interested in learning Pashto, the tango, embroidery or a new sexual position. If she and Shiv didn’t push, others would be clamouring to get to him.

I’m sure, he said. If this were a noir and we were lucky enough to be no good, Luna my love, we would strangle and knife the Billionaire together, and enjoy our work. We’d wrap him in the rug, drag him out, shove him in the rubbish chute and buy champagne and a red car, and have sex. We’d steal his identity or change our names to Bonnie and Clyde. But that would no way transfer his dough to us. We’d have lost a pupil. It wouldn’t work. We are, unfortunately, in reality.

So true, she said. You’ve said it. What fucking shit reality is.

Envy is worse. It is a terrible thing.

It really isn’t, she said. Not if you use it as a guide to what you want. A map of the future. A direction. A destination to aim at.

Her best friend had asked, why help others to develop when you’re going nowhere? Why do so much for them and nothing for yourselves? Shiv, isn’t that a good question?

They were relaxed, lying down and drinking in front of the photograph. If they turned it, they could see themselves reflected in the glass. They talked as they hadn’t been able to since the miscarriage not long after they moved into the flat, a heavy loss which appeared to have cancelled their future, leaving them with few words and wondering how to go on.

Now they cheerfully discussed what a drag it must be, being so rich, with everyone wanting something from you, so that your friends all had to be loaded, until you were isolated with other billionaires. Of course, as isolations went, it would suit her. A villa by the Mediterranean in Italy with sublime views, fine linen, old paintings, good tiles in the bathroom and a home cinema; a little boat, and no anxiety about whether they could meet their costs.

You are very materialistic, he said.

Am I?

I had no idea. Is it the influence of your best friend? I like money, but not so much I’d work to get it. Apparently sex and money can make people mad, but I never imagined it of you, even after seven years together. You seem strange now. I look at you differently. You are unpeeling in front of me. I wonder what is really underneath?

I had no idea myself. Until recently.

Until he came? He’s done, or undone, something in you. In us. We can’t stop it now. What is it?

Not only him. Life itself. We are almost thirty. Answer this: are we going to be at this level for the rest of our lives? Are we? Is that how you see us?

No need to get sharp and cranky, he said. Let’s face it, we are going to remain forever at ‘this level’ unless one of us writes a hit record. We’ve tried for years. It’s getting late for fame and fortune. I believe Paul McCartney was around my age when the Beatles broke up.

Unusually for them, the argument continued the following day. He had begun to pack up their possessions, and, after work, trudging around flats they might rent, showing her photographs of possible places.

Grim and grimmer, she said, refusing to look at them properly and even pushing his phone away. She would rather sleep on the street or die than live there, even if they did have a photograph of Jimmy Page to cover the mould.

We do actually have to go somewhere soon, he pointed out. We can’t escape the fact that we must leave this area. We’ll have to travel on public transport to get back here. We’ll lose pupils. They won’t want to come to us for fear of their lives. But what can we do? We can only continue.

She was talking over him, of people they knew. One friend’s father would sell a painting; another’s aunt left them a house in Venice or the country; someone else sold a first novel to Hollywood. There were all kinds of stories. She wanted a story. Why the hell didn’t they have a fucking story?

Shiv, open your eyes. Look around, baby. We can barely see the sky for the cranes above us. There are lush new apartments with nice balconies and forbidding high gates being built all around. Maybe they’ll let us in to give a lesson, but we will never live there. Who are they for? Why not for ordinary educated people like us? We’re losing our place. You even played guitar in a bar the other night. I’m surprised they didn’t ask you to serve the drinks and wash up. I love you and hate to see you like that. Are we trash now?

Not quite. Patiently, he said they had to recognise that despite their minor complaints, they were the luckiest couple alive: unlike most people they had work they loved, and while there were shortages, didn’t they have enough of everything? There was always someone who had more, so why even think of that? Did she envy Bill Gates? Surely the Billionaire was frustrated too. Sam knew he was. Money couldn’t buy talent, and the Billionaire’s wish was to stand on stage under the lights and take a solo like Jimmy Page. He would never do that.

Are you asleep, she asked. Hadn’t he noticed anything about her, that she had started to hate her work; it would soon kill her spirit, doing the same thing every day with people who were mediocre and they had to flatter. Why wouldn’t he recognise her dissatisfaction? Her envy wasn’t the problem; he lacked ambition and hope, the engine that kept people’s fire alive.

He took offence. What else could they do but live their lives?

What could they do? She had many ideas.

Like what?

Stop being so polite, respectable and restrained.

For what purpose?

First off, he could open up and discuss their situation with the Billionaire. If the Billionaire had made himself so rich and inexplicably didn’t want to give them a fraction of it when it wouldn’t matter to him at all, he could easily help make them just a little bit rich. He could make suggestions. He must be full of good ideas and imagination. Why shouldn’t he help them? That would be a start. They could take it from there. She would tell Shiv what to propose.

Sam started to laugh; he couldn’t stop himself. This infuriated her until she said, if you tell me one more time that we are happy because we love one another and we love our work, I will knock you down. Okay? It’s complacency, and I want to change things now. I would sleep with him –

You would sleep with him?

Probably. Yes. Why not?

Why not?

Wouldn’t you?

No.

You’d want to watch though, wouldn’t you? I knew it.

He said nothing, and she walked out. He couldn’t find her and began to worry. He couldn’t search for her because he had to teach.

As the Billionaire was packing up his guitar and preparing to leave, Luna suddenly skipped into the room in her best clothes, put her arms around the Billionaire, kissed him, and more than thanked him for the photograph.

She’d had an idea. She wanted to ask him to supper at the end of next week, with just a handful of close friends. Would he come? It would be simple but lovely. Please, would he come?

Yes. He would love to. That would be very nice indeed. That was very generous. So kind.

It was a frenzy then. They made a shortlist of friends to invite. The cast would be made up of two other couples and a single woman to round out the numbers. The first people they asked, a couple who might be impressed but not over-impressed, refused immediately. Billionaires were no longer fat men with big cigars, fine suits and arrogant swaggers. But that didn’t prevent him being an exploitative bastard, even if he did work with wildlife.

Among the single women there was a rush. They could have sold tickets, filled a stadium and live-streamed it. But Luna insisted that everyone who came should be calm and classy; nothing slutty to embarrass them. In fact, she needed to know what everyone was wearing. In the end it had to be her best friend, who insisted, who then begged, until Shiv said they should relent.

The simple supper, which Luna referred to as an ‘investment’, took three days to organise. They scoured cookbooks and markets, bought candles, napkins and good wine, and cleaned and polished; they discussed the music extensively. They were almost broken before it began, certainly financially. Shiv said the Last Supper must have been simpler.

*

After it all, she collapsed. Reflecting on what had taken place, Luna refused to get up for three days. When Sam wasn’t packing – how sad it was to see their possessions in boxes – he sat with her. She was in a serious fever while she worked out some kind of puzzle; it would take a while.

The evening of the supper, the Billionaire, good mannered as always, had brought flowers and pudding; the others wine or ice cream. The table talk had been light, about exhibitions, shows and plays.

Luna observed him when she could, and realised that the Billionaire hadn’t really been silent, which would have drawn attention. What he had done was ask the others questions, keeping the conversation going. When he did speak, it was banal. If her best friend had insisted on sitting next to him – Luna said not on top of him – Luna had instructed her to ask him if he thought someone would be interested in funding a school for teaching music? He didn’t think it was a bad idea, but schools weren’t his area. He was a rebel, dropping out early.

One of the others, towards the drunker end of the evening, become bold and asked him if he knew of any killer investments, you know, at the bottom end, for poorer people. The Billionaire laughed; the wisest thing would be to keep your money in an ordinary bank. Never try anything exciting with money, he said. Just be cool.

As a surprise, he and Shiv announced they would play ‘Going to California’ on acoustic guitars. At the end, everyone applauded and asked for more, but it was all they had.

The Billionaire apologised and left, saying he had to get up early the next day to go to Africa, where he was expanding his charity. He had enjoyed the food and the company, and was delighted they liked the photograph so much.

They all crowded at the window to watch his black car slip out of their street.

How could he? Luna said, in front of everyone. I don’t believe it. The rare birds will be eating caviar. He brought us cake! That was what he gave us, after all we’ve done for him.

Oh Luna, Sam said, what gave you all that stupid hope, when nothing was ever really going to come of it all. Childish really!

Shut up, she said. Please. Let’s forget all this! Put on some music, I must take off these shoes! Everyone, we must dance and drink now! Shiv says we must live in the moment and when is the moment if this isn’t the moment!

Something did come of it. Usually in bed together they didn’t say much. Now she began to use the Billionaire’s name, and Shiv followed her. The Billionaire became an obscene stimulant. He was there with them, driving them here and there, roughly.

*

The following month they had no choice but to leave the flat and move south of the river, to a basement with bars on the windows. It was a dangerous and dirty area, noisy at night, keeping them awake. There were fewer pupils, and it had been expensive to buy new furniture.

The awful thing was – perhaps the thing, according to Shiv, which had driven Luna to her bed – was that her best friend had been asked out by the Billionaire. Not only that, after telling Luna this and completing the date, she refused to divulge a single thing about the Billionaire: whether she liked him, whether she was seeing him again, or anything at all. Not a word, a complete blackout, and Luna lost a friend.

The Billionaire continued to come for his lessons; he and Shiv were now working on Howlin’ Wolf. The Billionaire was making good progress, said Shiv, as the two of them sat there under the photograph of Jimmy Page. He really was smart.

The Billionaire mentioned that he wanted to start an amateur blues band with friends, to play charity gigs. He was wondering if Shiv would like to play guitar with them and produce the music. It would be a blast.

Hanif Kureishi’s ‘The Billionaire Comes to Supper’ is included in his collection, What Happened, which will be published by Faber & Faber on 3 October 2019.