Image caption Athitiya "Kratae" Eiamyai, 32, died after an illegal cosmetic procedure

They're beautiful, well dressed and for the right price will promote anything from washing powder to luxury cars.

But working as a product promoter or "pretty" in Thailand is an occupation where image counts for everything.

At 32, Athitiya Eiamyai had reached the age when most "pretties" start to find demand for their services falling.

For a decade she had batted her eyelashes and flashed a ready smile to promote everything from luxury cars to new mobile phones.

Thailand's "pretties" Promote and present at motorshows and trade fairs

Exclusively female

Paid between $80 and $120 a day

But for Athitiya, or Kratae as everyone knew her, retiring gracefully from this $100-a-day job was not an option. She had parents and siblings who depended on the money she earned and she told her friends she was determined to fight ageing every step of the way.

In the last five years of her life, she had invested thousands of dollars into altering the way she looked. Her skin had been lightened and she'd had several rounds of surgery to change her nose, narrow her jaw and augment her breasts.

But according to her best friend and fellow pretty Pim Saisanard, she still wasn't happy.

"Kratae used to say if you want to be a beautiful woman you must put up with pain," she said. "She wanted bigger hips to match her bigger breasts. And she said that would make her perfect."

Gel filler

There are two main procedures surgeons use to increase your buttock size.

The method most plastic surgeons recommend is to have fat sucked out from your stomach and reinjected into your backside. Kratae was lean and had no fat to spare so she looked at options which involved artificial substances or "fillers" being injected.

Image caption Thanat "Dr Pop" Natveerakul (centre) apologises to Kratae Eiamyai's parents at a police station

The filler is not cheap and despite Bangkok being one of the cheaper places to have surgery the procedure costs 80,000 baht ($2,666). So one of Kratae's friends put her in touch with Thanat Natveerakul, a stylish young man who went by the nickname "Dr Pop".

Mr Natveerakul was no doctor, and had very limited experience of cosmetic surgery, but he did have a good reputation among the ladyboy community, having helped many of them achieve a more feminine shape.

He agreed to meet Kratae in an apartment and inject her buttocks with a gel filler for a cut-price 40,000 baht ($1,333).

Exactly what went wrong with the procedure is still unclear. But in the minutes after the gel was injected Kratae complained that she was having trouble breathing.

It seems likely that instead of finding fatty tissue Dr Pop injected the filler directly into an artery. The gel would then have travelled into her lungs, creating a blockage which in turn led to her brain being starved of oxygen.

In a panic Dr Pop drove Kratae to the hospital but shortly afterwards she collapsed into a coma from which she never recovered.

Three weeks later her parents agreed that the ventilator should be switched off and she was pronounced dead shortly afterwards.

'Look different'

Image caption Ailsa Phaiboonnantanpong works trying to attract a crowd to her stall

The Bangkok's House and Condominium Show was the sort of event that provided Kratae with work year after year. Not surprisingly the pretties' smiles this year were more forced than normal.

A few days before many of the women had been mourners at Kratae's cremation.

Alisa Phaiboonnantanpong said she believed Kratae had simply been unlucky. She said the use of cheap unlicensed clinicians was rife, particularly for relatively minor procedures.

"All the pretties are having surgery," she said, "at the very least Botox."

Alisa herself is no exception. At the age of 25 she has already had a number of procedures, including the painful removal of eight teeth to reshape her jaw.

She says her aim and the image which many of the Thai pretties crave is what's known as the "Korean look". Light skin, an oval-shaped face and a high bridge on the nose.

If you don't have the surgery you will look different from the other pretties and you won't get the work Pim Saisanard, "Pretty" and friend of Kratae

With much of the pretties' work depending on personal recommendations, staying in with your peers is critically important.

"If one pretty has surgery to get a particular look then all the others will go too," Pim Saisanard said.

"If you don't have the surgery you will look different from the other pretties and you won't get the work."

'Pay-off'

Of course not all the illegal cosmetic procedures go wrong and when they do very few end up as disastrous as Kratae's case.

But at the Patunam Polyclinic, a cluttered private facility in the centre of Bangkok, Dr Thep Vechavisit said he was receiving an increasing number of people in need of corrective surgery after botched procedures.

He said some had been injected with baby oil and even olive oil as fillers.

"I worry about our Thai people's safety," he said. "You know why we have so many illegal practitioners? The Thai police aren't interested - they just get paid off and it goes under the table. As long as you have money to pay them you get away."

At the government-run Institute of Dermatology there was resignation.

"As demand for cosmetic procedures here keeps getting higher and higher, more and more people want to share in that market," said acting Director Dr Jinda Rojanamatin.

"So all these people who have worked with doctors want to run a practice and it's illegal."

Dr Rojanamatin said the Ministry of Public Health were concerned about the problem but simply did not have the manpower to respond.

Thanks in part to the media attention it generated Kratae's case has not gone away. Dr Pop has admitted playing a part and was arrested immediately and charged with recklessness causing another's death and performing an unauthorised medical procedure.

He could face up to 13 years in prison and fines of up to 50,000 baht.

Already famous for its counterfeit CDs and DVDs, Thailand now has a growing reputation for cheap and sometimes dangerous cosmetic procedures.