Mason N Forbes is a very good photographer as well as an excellent writer – he took the eye-catching photo of the streetscape around Belfast's once notorious Albert Clock area for the cover of his new crime-thriller and attracted some unwanted attention in the process.
"It was one warm evening last July and I wanted to capture the tail lights of passing vehicle – I was taking a lot of shots when I felt a tap on my shoulder and a policeman was asking 'what are you doing?'" he laughs.
"The fact is that 80% of the sex workers I met were escorts. I didn't attempt to go near street workers. I didn't want to be going around the streets looking for them."
It's the first and only time the mysterious Mr Forbes seems to relax during our awkward phone interview to discuss his well received second novel, Bittersweet, a gritty crime thriller that reveals the seedy underbelly of the world's oldest profession.
It centres on a university student working as an escort to pay her fees, who learns that three girls in her building are the victims of human trafficking and teams up with a fellow prostitute, a migrant from Eastern Europe, and a client who is deeply attracted to her, in an attempt to save the girls from the clutches of their sadistic pimp.
Fascinating stuff, but it proves very difficult to get a glimpse into the author's mind and background. For a start, he won't tell me what his real name is – Mason N. Forbes is a pseudonym – or where in Northern Ireland he was brought up.
"I'm not prepared to give you my real name at the moment," he says directly. " I have a family and I want to keep some privacy for them, specifically on this topic. I'm very wary, very leery of this; my real name puts it out there, and you and I have never met each other ..."
The preference for a pseudonym is understandable but the complete privacy scenario is very odd indeed for anyone wishing to promote a book. Usually publishers are pushing their authors to talk about their personal lives to sell a few copies.
Forbes did a lot of intensive research into sex workers for Bittersweet. Is he worried that if he discloses his real name, the assumption is going to be that he has been running around with call girls?
There's a long pause.
"It's the controversial nature of both the sex trade and sex workers – people out there have a very anti view of it," he explains, eventually. "I've been following the debate here and it's very bitter and divisive. Sex workers are stigmatised and if their identities are revealed they often have to leave the country. I had very mixed feelings about doing this interview – please don't take it personally. I have allowed you to have a photo of me..."
The photo he refers to shows the writer in profile. He was born in England but brought up in Northern Ireland by his father, an insurance underwriter, and his mother, a teacher.
After studying economics at Queen's University, he worked for an engineering company before moving to Germany for 16 years and setting up a retail business selling whiskey, mostly Scotch. He married a German goldsmith and started writing when the family moved to Holywood, Co Down three years ago.
The years away have left him with an indefinable middle-class accent. He agrees it's quite a leap to go from economics and the business world to writing fiction.
"It's often the case, it seems, that authors don't really know what to do with their lives and then they discover that they want to write ... I had an itch to write and when I got into it it became a compulsion."
The idea for his first fast-paced crime novel The Strontian Factor had been simmering away in Forbes's mind for many years and went through several edits and re-writes before it was published. The novel drew some criticism for its inclusion of a first-time escort, which prompted the writer to thoroughly research the prostitution business, contacting escorts through their ads.
"I was spurred on to find out why there is such a reaction to the subject," he explains, haltingly.
"I wanted to attempt to understand the character of sex workers. They're always background characters in literature. I wanted to find out, what's the problem? I read about 20 books on the subject, from academic works to exposes of the slave trade, and watched a lot of TV programmes – on German TV there are more documentaries made on the sex industry."
Bittersweet took a year to research and write. Its publication is timely, with the Stormont government considering the introduction of laws to criminalise prostitution and make the purchase of sexual services illegal.
There are still no dependable statistics on the extent of human trafficking in the UK. Debate is currently sweeping Europe as to whether criminalising the purchase of sexual services will reduce the incidence of trafficking and sexual exploitation. Forbes fears for the future of sex workers if the law – based on Swedish legislation – is widely implemented.
"I felt a great empathy, if that is the right word, for the escorts," he admits.
"I didn't know what I was going to be dealing with when I started researching. The people I met were extremely friendly, very normal people. Of course some you are on the same wavelength with, others not. I do admire them for doing something that as a man I can't understand. I really do have a deep feeling for them."
"These people are doing what they do to pay bills," Forbes says simply. "I don't want to say yes or no as to whether I met any that enjoyed their work. Some referred to clients in the categories of the good, the bad, and the ugly. You need to be very strong emotionally and mentally to work in the sex industry. Usually they have an exit strategy in their head, like the student in my book, and will leave the industry when they are debt-free. I never met anyone who wanted to stay in it for life."
Forbes has succeeded in conveying the realities of prostitution, to cut through the superficial veneer which has effectively glamourised the subject of escorting in recent years, through the popular 'escort expose' novels and memoirs like Belle de Jour.
His brutal portrayal of the victimisation of women in the sex industry is more akin to Steig Larsson's epic novels, and he was astonished by just how different the media's representations of the lives of sex workers are to the nuanced reality.
In researching the industry he found women and men who have chosen to work in the industry to pay bills, finance mortgages and avoid student debts.
"I didn't set out to write a sex book," he says at the end of our conversation. "It is a very clean book; it's not an erotic novel. There's no swearing and there are no sex scenes as such, although they are in the background. It's not explicit. I tried to put myself in the shoes of an escort and I hope people like the book, as a crime thriller."
Bitter Sweet by Mason N Forbes is available online at retailers including Amazon.co.uk and can be ordered at all good book stores.