Tropicana is an expensive beach club on Cala Jondal in Ibiza. The loungers have crisp cotton covers, the juices are freshly squeezed and the staff wear natty, tennis club-style whites. There are massage therapists working under the trees. A socialite tells me about the last time she visited: “My friend came over rather flushed and asked to borrow money so she could give the massage guy a bigger tip.” Because allegedly, after asking if it was okay to work on the whole of her chest, the therapist had gone on to expertly bring the lucky girl to orgasm.

There has long been a tradition of the gentleman’s “happy ending”. Back when Indian barbers were eunuchs, a chap could get a shave, a haircut and, afterwards, fellatio. In the Far East today, prostitution still takes place around “barber shops”, much as a certain breed of western “private sauna” or “massage parlour” rarely harbours highly trained Swedish masseurs. But this is not to say that the odd proper therapist doesn’t offer soothing extras, too.

A few years ago, on his honeymoon, Kevin Costner was accused of exposing himself to his masseuse at the Old Course Hotel Spa at St Andrews, and then proceeding to ensure that his “ending” was a self-induced “happy” one. Costner has always denied the allegation, but it was too late: the happy ending had gone mainstream.

For a man to be asked, “You want everything?” is not — in certain geographical locations or clearly signposted establishments — that unusual. For women, though, it has formerly existed as a disquieting crossing of personal boundaries. From posh gyms in London to misadventures in Indian spas, many women have tales of male therapists making them feel uncomfortable. Friends sometimes tell of dating their masseurs, or, in the case of one, getting off with him then and there in the treatment room. So far, so Samantha Jones.

Yet with our burgeoning love of spa culture, is it reasonable to suppose the odd naughty or, perhaps, “progressive” massage therapist might slip through the net to please a certain type of upmarket lady?

Recently, there has been chatter in the New York press about just such shenanigans in upscale Miami hotels and New York bathhouses: the female “happy ending” is out there. Grant Stoddard, the author of Working Stiff: The Misadventures of an Accidental Sexpert, tells a story that illustrates the Jackanory finish is not confined to men, and possibly on the increase. “An ex went for a regular massage. It was her first time at this establishment, and the receptionist suggested that she get her massage from George. She called me two hours later to ask me if it was okay that a Chinese guy in scrubs had brought her to orgasm six times. I was more impressed than anything. My girlfriend recommended George to several friends, most of whom went to the massage parlour. George, they were told, had been let go, and nobody hinted at ‘happy endings’ being on offer.”

I rang a New York friend to ask if she knew of any “Georges” in a town known for its demanding girls. “It’s an urban myth,” she howls. “You always hear about the guy who gives a ‘happy ending’, but when it comes to the crunch, nobody has his number. Ever.”

So I set out to find — if not experience — some “happy endings” in London myself, and posted an ad on Gumtree. In 20 answers from both genuine masseurs and dodgy chancers, I found one guy who offered “delightful Hawaiian lomilomi massage the naturist’s way”. Another came with several qualifications, including a diploma in sports and remedial massage. As I posed as a nervous potential client, he explained: “I try to make people relaxed and happy. The ending is sensual and arousing, but it is done without any form of penetration. I do know how to give an amazing orgasm without .” We talk a little about pressure points and human anatomy. I wonder how he broaches the subject of “extras”? “When you massage a person, you ask how they want it: soft, medium or firm. You then ask what parts they want massaged: if they say yes to inner thighs, buttocks and the chest, and if they want to be totally naked, you generally get an idea of what they really mean.”

Technically, with women’s erogenous zones so much less defined than men’s, the “happy ending” is a grey area. What is actually a benign, relaxing massage for most could be sensual ecstasy for the overexcitable or an excruciating invasion of personal space for the physically shy. But talking to this particular “therapist”, it is clear that his “extras” clients are not surprised by how his massages end.

One of his qualifications comes from the Manchester School of Massage, where a spokeswoman, Lucy Johnson, says: “As soon as the therapist feels uncomfortable, we [teach them] that they should stop and leave the room.” She found my insistence that one of its alumni offered “happy endings” unbelievable. Wendy Kavanagh of the General Council for Massage Therapy gave me equally short shrift. “This is a therapeutic profession to be classed alongside chiropractic or physiotherapy, and if someone is offering sexual services, they should not be allowed to practise.”

How, then, to regulate the emergence of the practitioners of tantric therapies, for whom the yoni massage is part of an ancient Indian tradition? “Yoni” is the Sanskrit word for “divine passage” — the vagina, in western parlance. I asked the receptionist at Cosmic Touch Creative Therapy whether it offered yoni massage. And yes, indeed, it did. “It is a beautiful, relaxing, full-body massage, enjoyable and healing. Many women, not just lesbians, find they enjoy the sensual touch of another woman.”

At Cosmic Touch, it is obviously important that the client is compliant. Without such demand, we wouldn’t be looking at the small but growing number of tantra practitioners in this country. “The point of our tantric treatments is to cause your sexual energy to rise. Obviously, if our goddess does something to you that you feel uncomfortable with, this will stop the flow of your sexual energy,” says Cosmic Touch.

Why are we so nervous about “happy endings”, when, as many people say, sexual arousal is a matter of being aware of pressure points, and not necessarily a grubby scrum “down there”? Since more and more women are single these days, I wonder if “happy endings” could become the empowered woman’s solution to sexual frustration — sparing them the sordid disappointment of one-night stands? Until relatively recently, hysteria in women was ascribed to either a lack of sex or no gratification from it; physicians would massage the poor patient’s genitals to induce what was medically termed “paroxysm”. Dare I suggest that massage therapists might have the same equally pragmatic approach to the human body?

Would “happy endings” become acceptable if all your friends were doing it, too? A bit like Botox and cocaine, it’s ostensibly a dodgy sort of business, but its definition as such is dictated by your peer group. On a ring round, I found even sexually adventurous friends said: “Nooo!” One told me that when she met her boyfriend, she stopped her entirely proper visits to a male masseur because she felt strange being naked in front of another man.

Even the sexually upfront and enlightened Sam Roddick of Coco de Mer is not keen: “Tantric massage is one thing — it has philosophy, methods and it’s an empowered situation. I can’t imagine other instances where either client or practitioner isn’t being exploited. So little commercial sex is ever fair-trade. I heard there is a guy practising tantric therapies in London who offers G-spot massage. Are you having a laugh?” she hoots. “I’m not paying for that — come on, he’s a bloke. We’re so hazy in our sexual boundaries. And the exploitation goes both ways. A friend told me about getting a ‘happy ending’ from a masseur in Thailand and she had the same justification as men do when they come out of a dodgy massage parlour.

“Women: there’s a lot of free sex out there. Why would you want to pay for it?”

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