If social workers and police are correct, Gayman and Rice are just two among a new crop of teenage boys jumping into the trade known as compensated dating, which until now has been the preserve of teenage girls.

Like girls, boys advertise themselves online and receive cash for their time, initially going on dates with clients, and eventually providing sexual services to them.

Tse Kei-leung, supervisor of the CARE Project, which combats compensated dating, said he believed that the number of boys engaging in the activity was on the rise. 'In newspaper reports and through social workers and teachers, we have been hearing about boys engaging in compensated dating,' he said.

Police said they had noted 'the new trend of boys involved in compensated dating', though they did not have specific data on it. 'The problem raises our concern and we are spending resources to gather information through cyber patrol and intelligence collection to monitor the situation and work in partnership with some NGOs.'

Chief Inspector Sandra Chui Yui-luen, of the West Kowloon crime prevention office, said police had also seen boys advertising themselves for compensated dating.

In recent months, men have landed in court for using the services. Two months ago, the Court of First Instance jailed two men, aged 27 and 35, for paying for sex with a 14-year-old boy who they had met online. The boy in that case said he needed money urgently.

Last month a teacher appeared in a magistrate's court on allegations that he had engaged in oral and anal sex with a 13-year-old boy. He was suspected of having had 'compensated dates' with seven other boys. His case was adjourned while police investigate further and for prosecutors to seek legal advice.

Unlike girls, who seek out men, boys look for clients of their own sex and tend to be homosexual themselves. 'Some are thinking that they might be gay, and will try compensated dating out as one of various methods to experiment with their sexuality,' Tse said.

According to Tse, cases involving boys than girls were more complex. 'Besides dealing with the problems of compensated dating, we have to deal with the sexuality issue.' Boys could also face more dangers if their clients did not use a condom because they tended to engage in anal sex, which increased the chances of disease transmission, he said.

Despite anecdotal evidence of a rising trend, statistics are hard to come by. Tse said he knew of only 10 boys who had been involved in compensated dating in the past two years. Chui said no boys had been charged with criminal offences arising from compensated dating.

Asked to disclose the number of underage boys charged with soliciting and the number of men charged with sexual offences involving underage boys, a police spokesman said no gender breakdown was available for such cases.

The Social Welfare Department said it was not aware of any boys in children's or juvenile homes who were involved in compensated dating.

But, in Kowloon West, Chui said: '[The fact] that we do not have the numbers does not eliminate the possibility that there are boys who are participating in such activities.'