For Hong Kong's "part-time girlfriends", social media provides an easy way to connect with clients looking for sex, but campaigners warn that online convenience is tempting girls as young as 13 to put themselves at risk.
The label "part-time girlfriend" is a euphemism often used by young women in the city who may be studying or have jobs, but who also offer sex on the side.
By using variations of the hashtag #ptgf as shorthand, they connect with men on networks such as Instagram then switch to direct messaging to offer services and arrange to meet.
Instagram says it has made #ptgf and #hkptgf unsearchable, but a host of new alternatives that add Chinese characters or initials to the original tag circumvent the block.
Loneliness, curiosity, family breakdown and financial pressures are key motivators for young women to try it out, according to support workers on the ground.
High-school student Kiki, a pseudonym she chose to protect her identity, started part-time sex work aged 17, saying it was easy to search for men on Instagram by using one of the #ptgf tags.
"I had an argument with my sister and was not very happy, so I just wanted to find someone to listen to me," she told AFP.
"For the first few times I felt quite good... so I kept looking for clients for company."
She admits she was nervous about meeting strangers, but the financial incentive outweighed her doubts.
"My family is not very wealthy. I was making money for myself and saved it," she says. Kiki says she charged from HK$300 ($38) for dinner or "touching", up to HK$1,000 for other sexual services.
After less than a year she gave up because she had started a new relationship.
Now 19, she says she is left with a sense of regret and warns other girls to think carefully before taking the leap.
"A future boyfriend or husband might find it hard to accept," she says.
"It's like you have a needle piercing your heart and it's always there."
- Blurred boundaries -
Connecting with clients online often gives young women a false sense of security, says Bowie Lam, executive director of Teen's Key, a charity that offers support to Hong Kong's sex workers under the age of 25.
She says the age of "part-time girlfriends" is getting lower and believes that social media is a factor.
"They think they have autonomy and control because they can screen a client online, talk with him, but it makes the boundary more blurred," Lam says.
These young women often do not see themselves as sex workers because they are not based out of seedy rooms, or the bars and clubs of Hong Kong's traditional red light districts, she adds.
Sometimes they meet clients without offering sex at first and are taken to theme parks, dinner or even on hikes, but as more money is offered, the path usually leads to paid sex.
Some young women have their first sexual experience as a "part-time girlfriend", says Lam.
Believing they have become friends with a client can lead them to drop their guard.
"Girls have been treated violently and even raped because they trusted the man wouldn't harm them," Lam told AFP.
- Addressing taboos -
Hong Kong police said they have taken action against websites, chat rooms and discussion forums to combat "illegal prostitution activities" in a statement to AFP.
The "act of prostitution" in itself is not illegal in Hong Kong, police say, but soliciting is.
Instagram told AFP it acts to "swiftly remove" content, accounts and hashtags that violate its community guidelines.
A long-term strategy addressing taboos around talking about sex within schools and families in Hong Kong's conservative society is what is most needed to stop girls putting themselves at risk, says Lam.
Teen's Key offers young sex workers a range of support services, ranging from health tests to career advice and help with financial planning.
Lam says they want to help the women reconnect with their dreams and aspirations.
However, even when they are given support by the charity, some feel they cannot leave part-time sex work behind.
As the cost of living in Hong Kong soars, financial pressure is often the main factor.
Nicole, also a pseudonym, aged 24, started at the age of 18 to make money to put herself through college.
She found clients on online forums then communicated directly with them via the popular messaging app WeChat.
She now has a full-time office job, but still does after-hours sex work to pay off her college debts as her family cannot afford to help.
Nicole sees what she is doing as a practical solution but admits it has taken an emotional toll.
She describes sex work as a "dark patch" in her life and says she will feel guilty about it with any future boyfriend.
"I don't think I'm a pure person, I feel like I'm very dirty. If someone else wanted to do this, I wouldn't recommend it," she told AFP.
But she urged people not to judge young women who have made the choices she has.
"Maybe they are in need, or have problems they can't solve," she said.
"There isn't anyone who does this job because they want to."
Nicole, a pseudonym she chose to protect her identity, has a full-time office job, but still does after-hours sex work to pay off her college debts
Nicole describes sex work as a 'dark patch' in her life and says she will feel guilty about it with any future boyfriend
Young women often do not see themselves as sex workers because they are not based out of seedy rooms, or the bars and clubs of Hong Kong's traditional red light districts
High-school student Kiki, a pseudonym she chose to protect her identity, started part-time sex work aged 17 and says it was easy to search for men on Instagram by using one of the #ptgf tags
Hong Kong's 'part-time girlfiends' meet clients online and sometimes are taken to theme parks, dinner or even on hikes at first, but as more money is offered, the path usually leads to paid sex