With Memoirs of a Geisha coming to the cinema soon, Japan's geisha talk to David McNeill about heavy drinking, male egos and sex.

Fresh snow dusts the narrow streets of Gion in Japan's ancient capital Kyoto on a wintry night, but inside the Harutomi ochaya (tearoom) all is warm feminine cheer. The small room in the city's old geisha district is a comforting fug of sake fumes, rustling silk and the mellifluous sing-song voices of three women who flit around the handful of male customers.

Wrapped in lustrous-patterned kimono, black eyes framed in chalk-white faces under gaudy ornamental wigs, the two older geisha are mesmerising confections, moving with the graceful ease of dancers. Their attentions don't come cheap: the bill for an evening in an ochaya runs into hundreds, sometimes thousands of euro; star-struck men have been known to bankrupt themselves in places like this.

The youngest of the three, 17-year-old Miehinna, is a maiko, or apprentice, three years from being a full geisha. Beneath the make-up is a sprinkling of adolescent pimples and when she smiles her teeth are endearingly crooked. She is looking for a danna (literally master, or a male patron who financially supports geisha) who will pay to have her teeth fixed, ultimately look after her and, perhaps, take her virginity.

Gion, the setting for the new movie Memoirs of a Geisha, has always had its own rules. In its heyday, this was a pleasure quarter of squat wooden bars and teahouses run almost entirely by women in a male-dominated world. Formal social agreements such as marriage and even family ties had little meaning here and it was one of the few places where female babies - many born outside marriage - were treasured.

Today, the number of geisha and maiko in Gion has fallen from more than 2,000 in the 1920s to perhaps as few as 200 today, reflecting their decline countrywide, but the area is still a closed world to most ordinary Japanese. Entry into a teahouse is by introduction only, and secrecy is prized. And although the system of patronage by rich men who seek out geisha as status symbols or concubines has faded, it survives.

"Ideally, we want a prosperous older man who will not want to sleep with her," says Miehinna's "mother" Noriko Wakabayashi. "It's not a question of sex, but of who will be able to look after her." Like most geisha in Japan, she has read the Arthur Golden book on which Memoirs of a Geisha is based, and takes exception to its depiction of a maiko's sexual initiation, known as mizuage.

"We don't auction the girl's virginity," she says contemptuously, but still insists that Miehinna cannot choose who to sleep with. "That will be decided by me and the patron. Of course, it is not like the old days where she had absolutely no choice in this. If she does not like the man, she can refuse."

What if she falls, like other teenagers, in love with a boy her own age? "That cannot happen," says Wakabayashi firmly. "She is not a schoolgirl. She lives here and knows the responsibility of being a maiko, and the traditions of this world."

In Memoirs, the eponymous young heroine is sold by her poor family into an okiya, or geisha house, a common practice until Japan began its climb to postwar prosperity.

Today Miehinna is one of hundreds of young Japanese women who freely chose to become a maiko once she finished junior high school at 15. "I was attracted to this life," she says. "I have the chance to meet so many interesting people and to learn and study."

She claims she has not told her friends about her job, nor have they asked. "They would not understand this world." Gion is one of the few places left where she can still be trained in the geisha arts - singing, dancing, playing, even how to pour drinks and speak in the refined Kyoto dialect, but above all, smooth conversation.

The training can be difficult and the work hard, mostly made up of long hours in heavy, stifling costumes pampering male egos. Many women develop bad backs and liver and kidney problems from heavy drinking, and bald spots from constantly teasing their hair into shape.

Miehinna's job spec, such as it is, is to be the object of male fantasies. The top geisha have reached a level of skill and sophistication that has elevated their craft to a high art, championed by official Japan in tourism brochures and guidebooks. They point to the literal meaning of geisha - arts person - and see themselves as curators of a dying tradition, disparaging the "fake" geisha who they say have helped confuse their trade with prostitution.

"It's better not to think of geisha as selling sex," says geisha historian Hiromitsu Mushiake. "There are so many other things to choose from if you are a man these days. In the past geisha were bought and sold like slaves, and sold themselves too, but that situation has changed. They have the upper hand now."

Still, confusion reigns about what a "real" geisha is. This is particularly true in Atami, a faded hot springs resort-town about an hour's train ride south-west of Tokyo, and home to about 300 geisha. This is the geisha second division, often contemptuously referred to as the centre of "onsen [hot springs] geisha", a euphemism for prostitution.

Today, about a dozen women are preparing for a busload of tourists who will come to see them perform the clumsy butterfly and other traditional dances. The women range in age from early 20s to almost 70, and underneath the geisha war-paint, their faces are tough and worn. Some have been up until the early hours drinking with clients in local hotels and restaurants.

Thirty-year-old Chizuho says the boozing is the hardest part of the job. "I was once ferried to hospital after downing a bottle of whiskey."

Like the rest of her colleagues, she sits perfectly straight with her kimono hanging low at the nape of the neck, considered one of the most erotic parts of the body in geisha culture.

"You have to protect your health," she says, dragging on a cigarette, bloodshot eyes standing out cruelly in her alabaster makeup.

While not lucrative, geisha work in Atami pays much better than the office drudgery many of these women might otherwise face. A good Atami geisha can earn €45,000 or more a year, including tips, although they must pay a percentage of their earnings to a local union and fork out for their own kimono, wigs, obi-belts and makeup, an ensemble that typically costs more than one million yen (€7,380). Some have found other ways to supplement their income.

Hotaru became a geisha 17 years ago after falling into debt in her teens and says sex with clients is an option.

"It depends on the person. With other forms of prostitution you can't refuse a client, but in this business, you might meet someone that you like as a person and take it from there. It goes on in any world where men and women meet. The woman can of course refuse, but if they like each other they might negotiate a price, and she'll be his wife for a night."

The accusation that geisha is the flesh trade dressed up in silk finery enrages traditionalists and many of the older women who vehemently deny its dark undertow.

"Absolutely nothing like that exists," spits 56-year-old Komami, who is a third-generation geisha and has been married for more than 30 years. "In the past those things happened but no longer. If I had a daughter she would continue the family tradition."

See also: 'Asian invasion', in tomorrow's Irish Times Magazine. The film Memoirs of a Geisha opens in cinemas Jan 20