The two lovers are not even naked - yet this was the sexiest painting at Art 99, the big annual London Contemporary Art Fair that took place last month. It sold for pounds 15,000 and Tom Hewlett of the Portland Gallery reckoned he could have sold the painting several times over.
We've mostly all been there; have learnt to interpret the body signals of the opposite sex, then swapped notes among giggling groups of our own gender. The wonder is why, when so much art is about sex, so few artists have shown it as it is played out in real life, as Vettriano does. There's obviously a problem here. And it is made no easier for Vettriano by the fact that he is a former coalminer in his native Scotland and a self-taught artist, too.
Art critics, especially south of the Border, have studiously ignored his work, despite - or perhaps, because of - its popularity with private buyers. A few disdain it as soft porn. No public galleries have bought it. Why can't he paint miners with blackened faces blinking in the dawn light? Why must his courting couples circle one another in bars and dance- halls, wearing collars and ties and skimpy dresses? Such second-rate glamour. Is that the correct way to represent the working class?
The fact is that that is how the mating game was enacted in the Fife of Vettriano's youth - and still is. He is 45 now, was down the pit between the ages of 16 and 20, and recalls: "I couldn't wait to leave school, get a job, buy my first suit and get into the Friday and Saturday night dancing. Those who glamorise the pit are those who weren't there. I was bloody there, and I can tell you there was bugger-all to call romantic."
And now? What about the couple in Game On? "They're not scraping around for money. The mining valley has become silicon valley. Japanese electronics companies have moved in. All we could afford at those weekend dances was Coke, but those two probably have a couple of bottles of bubbly in the fridge. That little black dress is a provocation, but she probably paid no more than pounds 9.99 for it in a department store."
And the sex? Aren't the working class supposed to do it with the light turned off and their socks on? "In my youth, I never noticed any stiffness towards sex. We used to do it wherever we could - behind the Co-op, on the beach, in bus shelters. Looking back, it was dreadful, but I still feel a great fondness for those times. It was a great way to get into adulthood."
He says: "I sometimes get the feeling from critics that sex itself is not correct, that they'd rather have a landscape. But we live in a world where people are sexually driven. It is a powerful thing, powerful enough to unseat presidents. People are desperate for it. Voracious. Men will do any bloody thing to get it. They will go back to the same woman, to the same brothel, even though they know they are on the road to destruction. It is like being an alcoholic.
"In my paintings, people know this. They dress glamorously and the atmosphere is highly charged, but they are not particularly happy. They know that things are not likely to work out. They neither know nor care whether they will see the person they are pursuing the following day."
Vettriano now has a studio in London. He is selling his mansion in Edinburgh and intends to buy a smaller house there. He paints all the time. His marriage broke up at about the time his paintings began to sell.
Prices: you can still buy a 12in by 10in canvas for around pounds 3,000 ('Game On' is 40in by 30in) from the Portland Gallery (0171-321 0422); the less provocative paintings - dancing on the beach, bar scenes - have been published as prints by The Art Group in the standard sizes 40cm by 50cm (from about pounds 9) and 60cm by 80cm (from about pounds 18); they retail at print
stores such as Athena, the Art Factory
and House of Fraser