"I was there on my own and she said, 'What do you think?'
And I said, 'Get your roots done and straighten your hair'," recalls John. "She came back in the next day with it done. It said to me: 'This girl means business'.
"Then a couple of days later I had her in with Barry McCall doing a shoot - he's one of the top fashion photographers. The shoot was amazing and it took off from there."
The girl in question was Katy French, who became one of the most in-demand models on the scene, but died tragically of brain damage linked to cocaine use at the age of 24 in 2007.
"It was a huge shock when she died. The funeral was very sad," he reflects.
"Drugs wasn't that common on the modelling scene in Ireland; you'd be surprised.
"A lot of what you hear about models is not true. Abroad and internationally you would see it, but in Ireland it was not part of the scene at all because if you were seen or caught doing that, you'd get shunned immediately. I never saw it in this country, ever."
John hails from Blackrock in south Dublin and went to art college in Dun Laoghaire, before moving to London. It was there, aged 20, that his chiselled jawline and good looks caught the eye of a model agency scout.
"I was in Leicester Square and I was outside a cinema. I was approached and asked, 'Have you ever thought about this?' I had done because I was in art college and in the photography section I did a few shoots beforehand," explains the 5'11" Dubliner.
His first big ad campaign in London was called 'Suits You'.
"You'd go to a casting and you'd see somebody coming out. One of them was for a Next show. You'd queue for two hours before you were seen and if you get the job it was worth 70 quid," he recollects.
"I went where the money was. I used to do catwalk and fashion shows. Then I joined an agency and did a few jobs and moved back to Dublin.
"I did it as a few extra jobs here and there. It was more fashion shoots and advertising. That's where the money jobs were. I didn't think of it as a full-time career or anything like that."
He got a job as a booker with Assets, where he helped make Katy French into a star, and then set up his own business, Compton Model Agency.
"I set up my own agency for about 10 years, which is a long time, and it was a long time ago. It went very well and was doing great and I was passionate about it," he reveals.
Among his clients were the likes of Gail and Siva Kaneswaran (who went on to join The Wanted as a singer), and another tragic model, Alli MacDonnell, who sadly took her life three years ago after posting about being targeted by online bullies.
"Alli was my best friend as well, that was very tough and still is," he sighs. "I'm very much involved with the family and still in touch with them. We share photographs and memories together."
His agency was initially flying. "A lot of the girls were working models. They'd do TV3 [now Virgin Media], Ireland AM, Xposé, shoots, shows, a lot of stuff for the industry. We were kept busy and working away.
"A lot of clients came into the office and they would go through the books looking for guys, and then they'd look at me and say: 'Actually we want you'. That happened a few times. But as the years went on they stopped asking," he laughs.
But then the recession kicked in. "Unfortunately, the way the market went when the crash came, it destroyed the industry here in Ireland," John describes.
"At the time it took me about a year to shut it down and it broke my heart. It was a business I was in for about 25 years and it was very hard to let go.
"I had a little bit of a breakdown, as I do suffer from depression. There was lots of hassle paying off people," he continues.
"One person knocked on the door demanding €300, which I gave. There was a complete downward spiral after the agency, because it was like, 'Who am I now? What am I now after the agency is gone?'"
His rock during this time was his husband Marlon Jimenez Compton, who came to Ireland from Venezuela as a refugee and whom John first met in famed nightclub The George around 2004.
"We're really different but we are very alike, it's kind of weird. We are married. It's great the way the world has gone. I can walk through the park and put my arm around him without looking over my shoulder feeling guilty, which you couldn't have done before," he smiles.
The couple live in Castleknock, Dublin 15, and John works part-time as a rep for a fast-moving consumer goods company that can involve stocktaking and even placing items on shelves, which has surprised some former clients who recognise him.
"I have to pay the mortgage somehow," he says. "It pays the bills."
Since giving up alcohol last year he has got into a fitness routine and hits the gym early in the morning, and combines this with jogging and walking.
His new lease of life has inspired him to re-enter the modelling world and he has re-joined Assets and put together a portfolio, which has seen him win new clients such as Ailesbury cosmetic clinic.
"There's no men my age doing what I'm doing," adds John. "I'm just putting me out there to promote products for men."
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