It's a spectacular afternoon in Coogee, and we're sitting upstairs in the Pavilion with a view to the ocean. Perry orders the whole Holmbrae roast chicken for us to share, and sips on a Semillon blanc. Lucy Perry. Photo Nick Moir Perry was born in Johannesburg, South Africa, in 1973. Her family left the country when she was eight years old. Her mother was a schoolteacher – and a Baptist pastor – and her father was an engineer. They made their home in Turramurra, and Perry was sent to Roseville College. "I didn't want to go there," she says, "because it was a private girls' school, but it was what I needed. I worked out that it was really fun to be smarter than the other girls. I chose the subjects that the dumb chicks did, and then you can top those subjects. So I did three-unit art and three-unit textiles and design. I topped the state in textiles and design because all the dumbest chicks in NSW do that." She left school at 17 and went to work as a jillaroo, which "knocked the princess out of the private school girl", she says. At this point, she further endears herself by accidentally knocking wine from her glass into my mineral water, which is the kind of thing I normally do. She found a job as a junior creative with the advertising agency Pilgrim International. She lived with a friend, worked on cause-related accounts such as Amnesty and World Vision, and bought a motorbike. "I lived this fabulous life for six or eight months," she says, "working at a night club at weekends, riding a black, shiny motorcycle – I thought I was so clever – until I crashed my motorcycle.

"That brought my life to a grinding halt," she says. "I broke my leg really badly. I was in and out of hospital for a year. There was a six-week period where I had a major operation every Wednesday for six weeks. My leg was likely to be amputated below the knee. What saved my leg was surgery they'd been doing since World War Two, called cross-legged surgery. They sewed my legs together – which is quite ironic for a promiscuous 19-year-old. Lucy Perry leaving the Royal Commission into child abuse on 2 March 2015. Photo: Louise Kennerley "So I was a mermaid for a month, and my left leg fed my right leg with blood supply," she says. She rolls up the legs of her pants. "Usually, you have to make love to me before I show you this," she says. Photo Nick Moir

Each of her calves looks like it has been bitten by a bear. "I've never lost a scar competition in my whole life," she says. Perry married at 21 and "had three humans I pushed out of my vagina". She lived in Turramurra with her husband, Bruce, and started her own creative-services company. "Our last major client sold hinges and drawer-runners," she says. "It was so boring, I could've stabbed myself in the eye." Marketing hinges is "really tricky", apparently, "because they're inside cupboards, so you can't show the f---ers". In 2004, Perry took three steps to relieve the tedium. First she became a doula, or childbirth support person. Then she started up Beer and Bubs, a childbirth program for men, which still runs in pubs across the country. Finally, she became involved with the Addis Ababa Fistula Hospital in Ethiopia, after seeing the hospital's Australian co-founder, Catherine Hamlin, interviewed on the Oprah Winfrey Show. Perry priced her doula's fee at the cost of one fistula operation, then donated the money to the hospital. "But after travelling to Ethiopia and seeing the way women in developing countries suffer and do so with such grace and gratitude, I came back to Australia and I couldn't support women in this country any more. I found I wanted to slap the birthing mother, because she was being so ridiculously demanding." Perry channelled her relentless energy into communications work for the hospital and, in 2012, became CEO of a new organisation, Hamlin Fistula Ethiopia (Australia). In less than three years, she raised $7 million for a network of hospitals and a midwifery school. "I'm pretty proud of that," she says, "because it's pretty hard to raise money for a vagina charity. We were talking about smashed-up vaginas in Africa. That's a tough subject."

She tried to make it fun to deal with Hamlin Fistula. She launched an appeal to have people pay not to come to their Christmas party, but her most successful initiative was simply asking people to repeat what she had done as a doula and to donate $600, the cost of a single operation. "That made people feel fabulous," she says. Then came the Royal Commission which, she says "signalled both the beginning and the end of my life". She had contacted the police when she first heard of the investigation into Knox. She told them that, at 15 years old, she had travelled from Roseville College to Knox to appear with Knox boys in a performance of the musical Guys and Dolls. At a rehearsal, the headmaster had groped her in front of about 50 students, who had "roared laughing". She didn't want to press charges – "I couldn't be bothered," she says – but hoped her statement might lend an insight into Paterson's character. When investigators asked her to testify, she was happy to take the stand, and was overwhelmed by the support she received from the survivors of the Knox rapes. Thirty days later, she was fired from her job, by a board of volunteers. "They said I raised too much money in Australia," she claims, "so all the other entities around the world were intimidated." Then her marriage broke up after 20 years. "I didn't see that coming," she says. "So 2015 was a shit sandwich, on some levels." But she quickly fell into a new relationship. Her appearance at the Royal Commission had gained her hundreds of new followers on Twitter and one of them, "Doc" (because he has a doctorate) became her "landing pad". She lived with Doc for about eight months while her children, now aged between eight and 12, stayed with their father in Turramurra. Perry says she has always been the breadwinner, and she travels a lot for work, and the children want to stay at their schools – but also she can't bear to live on the North Shore anymore. It's "a slow way to die". So she spends hours driving across Sydney and back.

When Perry was offered the CEO's job at the orphans' charity Sunrise Cambodia, she flew to Cambodia with Doc, "And I saw stuff on the trip that was heartbreaking," she says. The charity's founder, Geraldine Cox, took her to meet a community that lived on a garbage dump and scavenged for food among hospital waste. One woman hacked open a garbage bag with a hook, found half an apple and ate it while she spoke to Perry through an interpreter. "And it smelt so bad," she says, "and Doc smells really nice, and I remember just burying my nose in his chest to get his smell." At this point, our lunch arrives. Strangely, thoughts of the dump (and fistulas) do nothing to put me off my chicken. Although I do feel guilty eating from a $55 share plate. Perry was in the news most recently in November, when she tweeted that the Australian Graphic Design Association (AGDA) awards night was a "joke" and a "sausage fest" because most of the winners were men. The association threatened to take action against her, which brought the story to the media. "The funny thing is," she says, "only a handful of people saw the tweets, until it was in the Sydney Morning Herald, and then a couple of million people saw the tweets." Perry noted the obvious appeal of the word "sausagefest​", and this month launched the Sausagefest​ campaign for Sunrise Cambodia, to encourage people to raise funds by hosting a barbecue. Saturday sees Sunrise Cambodia's International Women's Day event, Get the Girls Out, a swim at Coogee's women-only pool, McIver's Baths at 7am-9am.

She has already found a donor to fund an educational centre near the dump in Cambodia. She split up with Doc but there are now back together again. She knows she is lucky, that we are all lucky in Australia. "When you spend time with some people living on a dump, it makes you appreciate the basics of life so much more. I kiss my pillow, I love it so much." TIMELINE 1973 Born in Johannesburg, South Africa 1995 Married Bruce 1993 Started up creative services firm, Pure Graphics

2003 Son, Hudson, born 2004 Created Beer + Bubs program; began to volunteer for Hamlin Fistula Ethiopia 2005 Daughter, Harlow, born 2008 Daughter, Sheba, born 2012 Appointed CEO Hamlin Fistula Ethiopia

2015 Testified before the Royal Commission; removed as CEO Hamlin Fistula; broke up with Bruce; appointed CEO Sunrise Cambodia