"Spending his money would make me sick." Lila was abducted on a date with a sugar daddy.

Living a sugar baby lifestyle certainly has its perks; lavish gifts, instaworthy holidays, and an average monthly allowance of $2,900. Not bad for a university student used to bar shift paychecks.

An estimated quarter of a million young Australian women are dating older men for their money in the hope of giving themselves some financial freedom, often while they finish off their studies.

But there’s a very dangerous side to the arrangement, which has also been labelled “undercover sex work”.

Women who sign up for the sites are sold a fantasy of ‘dating’ and told that sex is not necessarily the end game, it’s optional.

But Lila says that’s definitely not true.

“If you’re not ready to have sex with the older men, don’t go on the website, because you’re putting yourself in that situation,” she told 60 Minutes.

Lila was like any other young girl who signs up, she was just hoping to earn a little extra cash.

She signed up to SugarDaddyMeet when she was barely 18, and on her second date using the service, she was abducted.

Her suitor had arranged to go to a restaurant near the botanical gardens, but the car drove right past and she started to get worried.

"I asked what was going on and he locked his doors and was like 'you're coming home with me'," she said.

Lila's sugar daddy demanded sex immediately, threatening her and telling her it was expected for the money.

She was dropped at the station afterwards, but refused to take the man's payment.

"I just wanted to leave," she said. "Spending his money would make me sick."

Lila was so embarrassed by the night she didn't go to the police, and she didn't tell her parents.

"It was too confronting and embarrassing for me at that time," she told 60 Minutes.

The man who abducted her had nine other complaints against him on the site. He was banned briefly, but was let back on with a warning.

Lila wants other young women, drawn in by the lure of cash and a lavish lifestyle to heed her warning: "It looked a lot better than it is".

UTS Professor Peter Fleming also spoke to 60 Minutes criticising the sites, "don't believe the glamour," he urged.

"This is sex for survival. By and large the glamorous sugar babies are used as the pin board advertising for the website but these are people who are generally economically desperate who need to pay for their university fees - this business model has found a way to exploit that desperation," he said.

For 60-year-old Bob, sex is certainly expected on his sugar daddy dates.

“It's not a charity,” he told interviewer Sarah Abo. "Sex is part of the package".

“For a woman to find a guy who's going to be extremely generous, without expecting sex in return, I would have thought is more the exception than the norm," he added.

“It’s not a charity. No I have a philosophy in life. I sometimes explain it to young women, and they don’t always get it,” he told the program.

“When a woman says to me, ‘Well, I kind of like the money but not give anything in return.’ I say, ‘Well you’re not really a good object of my philanthropy. I prefer to give it to a starving kid in Africa rather than to you.’”

While many young women who spoke to 60 Minutes claim the practice is "empowering women", listening to sugar daddy Nick talk about his conquests makes it sound like anything but.

He told Sarah Abo of his sugar baby formula, "Take the number of days you've been married, the number of times you've had sex and you divide that by your alimony and that's your price per f*** factor."

"Wow that's really cold," Abo told him as he laughed, "Yeah, it's your PPFF score."

He says he's even hired women from the site to hang out in his office purely for their looks, and he's been known to fly large groups of women to music festivals.

"I don't make them do anything that they don't want to do, but you know... They're there because they're young and beautiful, absolutely. I do have criteria," said Nick.

If you ask the founder of one of the biggest sites, Seeking Arrangement, he'll tell you he has successfully re-written the rules of romance.

“If you are poor and you are constantly hanging out with the poor people, you're never going to find opportunities in life,” Brandon Wade who has a 22-year-old sugar baby himself, told 60 Minutes.

"Everything when it comes to human interaction or human relationships involves some sort of economic exchange - I think it's time for people to own up to that," he said.

He used the example of his parents, his mum doesn't work and his father funds their lifestyle, "That doesn't make her a w****," he told the program.

"Every romantic relationship is transactional," he insisted.

Professor Fleming thinks the sugar baby fantasy has been well-crafted.

"This narrative that if you become a sugar baby then you can first of all have an exciting dinner and date and be doted on. I think the fantasy is important for attracting sugar babies but the flip side - the dark side if you like, is a certain economic dependence," he warned.

Read More: 24-year-old Alex on what it's really like to be a sugar baby.