Prostitution may be the world's oldest profession but in Hong Kong, a growing number of young girls have reinvented the trade and prefer to call it compensated dating.

Take Tabo (alias) for instance, who wrote about her encounter with a man on her online blog. Her description at first appeared as if she was referring to her new boyfriend but the man was a paying customer.

"It was a lovely evening. We had a wonderful dinner and drank a little wine to relax," said Tabo. "It was not my first time to sleep with strangers, but this time is different. It is a job."

She said she could earn up to HK$4,000 ($514) per date.

Compensated dating originated in Japan in the 1990s and has caught on in many other Asian cities including Hong Kong and Taiwan. The term means paying a woman, or a young girl, to be an escort, and usually sex is involved.

Most prostitutes do it for the money but these girls say they do it to make cash to buy material things they normally could not afford. For example, one girl in Hong Kong wanted to buy a pricey mobile phone strap that cost several thousand Hong Kong dollars.

Some are from troubled families but others just like the quick money.

Concerns were raised in 2008, when a client killed and beheaded a 16-year-old girl named Wong Ka-mui. The killer, Ting Kai-tai, 25, was sentenced to life imprisonment last July.

Even though police and social workers in Hong Kong say compensated dating is just another fancy phrase for prostitution, most of these girls do not consider themselves to be prostitutes because they feel they can walk away from it at any moment.