Mahmoud looks out over the chaotic mess of rooftops and aerials and towards the neglected park he now calls home. He's wearing a red hoodie, blue jeans and a black cap.
Everything suggests he is a typical 20-year-old, apart perhaps from the jagged scar on his brow. "I am ashamed about what I do for money, but I will tell you," he says.
"I had only two options when I arrived - one was to become a thief or a drug dealer," Mahmoud explains. "But I am not that kind of person.
"The other option was to stay in the park and have sex with older men, or anyone ... that asked for it for five or 10 euros [around $5 and $10] ...."
His only shelter is a cheap tent that he shares with an Iranian asylum seeker. Perched on the concrete roof of a small maintenance building hidden among the trees of Pedion Areos Park, it offers little protection from the cold. A bag of oranges provides breakfast, lunch and dinner.
Mahmoud says the money he makes selling sex only covers the cost of his daily food. He cannot afford to save anything.
He speaks regretfully about his work but sees no way out.
"This is my only source of money now," he says. "I've made a mistake, and now I'm deep in this s***."
But Mahmoud isn't alone. Pedion Areos Park has become a hub of illegal male prostitution, sometimes involving refugees as young as 15.
Greece has strict laws regulating prostitution. Sex workers must register, be aged over 18, legal residents in Greece and work in a licensed brothel. Despite this, illegal street prostitutes, who are often migrants and refugees, are estimated to outnumber licensed prostitutes by 20 to one.
Licensed sex workers have fortnightly sexual health checks and access to free treatment for sexually transmitted diseases. Unlicensed street sex workers, like Mahmoud, do not.
Shopping for sexWhile the majority of Athens' sex workers are female, Pedion Areos has long been a hot spot for male sex work.
The park, although grand and sprawling, has, like its inhabitants, been largely ignored. The large statue of King Constantine I that stands at its entrance has been covered with graffiti. Used condoms and tissues litter the ground.
Those familiar with the park say that the majority of the sex workers there are Albanian, Bulgarian and Romanian.
Neno, a Bulgarian Roma, arrived in Athens eight years ago and has been a sex worker in the park ever since. He says he doesn't particularly mind the work, but that it doesn't pay well.
"A lot of people hate this job, they don't want to be here," he says. "For me, it's OK. I don't have a problem with it. Just the money isn't good."
Neno isn't homeless. He lives in a small town to the southeast of Athens which is popular with tourists, and takes the bus into the capital each weekday. The bus stops directly outside the park.
At the weekends, he makes a little extra money playing guitar in tavernas along the coast.
For Neno, being a sex worker is a job like any other. For Mahmoud and the park's other homeless residents, it is a desperate attempt to survive. They spend their mornings waiting and warming themselves by fires started in steel cans, into which they put anything that will burn, often producing a choking smoke.
"The Greek guys [clients] don't come in the day because they think they might get caught," Mahmoud explains. "They wait until later to come to the park, when they'll be safer."
Business begins in the late afternoon as the winter sun starts to set and the few dog-walkers and runners leave the park. Their busiest time is from dusk until midnight, when the majority of those in the park are sex workers or their clients.
As the light in the park fades, middle-aged men walk slowly past benches on which young men and boys sit, as though perusing shop windows. By now, a different demographic has arrived: unaccompanied minors, refugees who have been orphaned, are travelling alone or have been separated from their family during the journey, and see the park as a place to make money.
"The main issue is that they have no money, either for their daily lives or to pay for a smuggler," explains Kenneth Hansen, the programme manager at Faros, an NGO that runs a shelter for unaccompanied minors close to the park.
"Some of them have told [us] that they have sex with men in order to do other things, to have money to go and buy a new phone," he says.
"One boy told us he had sex with two men and got five euros [$5] so he could buy cigarettes ... One guy told us he had sex with a man so he could pay to have sex with a woman."
The clients are always Greek, explains Mahmoud. Most are in their 60s, but some can be as young as 30; others as old as 90. "You see men of all ages [buying sex]," he says. "Some are young men and some look like they might die the next day."
Some of the sex workers are clearly on familiar terms with the clients, laughing and chatting openly with the ones they recognise. Others, often the younger ones, sit awkwardly, saying little.
"Usually the men see me in the park, they come closer to me then ask me, 'Where are you from?'" says Mahmoud. "I've learned a bit of Greek so I understand and we speak a bit. Then they sit down next to me and that's how it starts."
Once a price has been agreed, they move somewhere more private - but that usually just means going behind a bush a few metres away.
Costas is 46 and has good job at a logistics company. Most evenings after work, he goes home to his apartment in a suburb of Athens, where he lives alone. But three or four evenings a month he changes his clothes and drives to the park to look for sex.
His routine has been the same for 10 years, he explains.
"It's easy to find sex here," he says. "I normally stay for about an hour before I find someone to go with."
He is familiar with two or three of the sex workers at the park whom he knows by name and sees regularly. Five euros is the going rate, he says, regardless of nationality.
Costas insists that he never has sex with refugees or anyone under the age of 18. That would be "wrong", he says. But he does acknowledge that he can't be sure about the age or nationality of those he does have sex with.
Only his closest friends know about his visits to the park, he says.
Yiorgos says he is 52 but he looks much older. He lives an hour away but comes to visit a friend who lives near the park three times a week. They go for coffee and, on his way home, Yiorgos walks through the park, looking for sex workers.
"[The sex workers] are 17, 18, 20, 30, 50, it depends," he says. "The day before, there was one that was 16, small," he adds, before looking around nervously. "They should be 18," he admits. A sex worker in their 20s could have sex five times a night, earning up to 50 euros, he explains.
He doesn't believe that what he does is wrong. "If I steal, it's a problem. But I don't steal. Neither do I fight .... If I fight or steal, yes, the police will come. But if not, they don't come. What could they tell me? All they can do is ask me why I am sitting here. Is it wrong?" he says.
Prices vary, explains Tassos Smetopoulos, a volunteer who organises a weekly food donation in the park. "In Pedion Areos, it starts from five euros [$5] and goes to 200 [$213]," he says.
"Some of [the clients] say to the boys, 'OK, you can come to my apartment, to have a little party. Some friends of mine will be there too. You can stay the night.' Something like this can go up to 200 euros [$213]. It depends on what they're asking and what the boys accept."
|In addition to looking in the park, some clients solicit sex from asylum seekers in Athens' Victoria Square [Will Horner/Al Jazeera]|
Shortly after the US-led invasion of Afghanistan, Mahmoud, who was then five, left his native Herat with his family. "My father went first before us and then the rest of our family followed him," he says.
"Everybody in Afghanistan then who wanted to seek a good life usually went to Iran, so that's what we chose to do."
In Iran, his family lived on the margins, unable to find legal work once their temporary residence permit, which they couldn't afford to renew, had expired. After five years of schooling, Mahmoud started working to support his family.
I tell them Athens is a good city, with nice people, but really it's like someone has injected this city with filth
"I stayed for five years in Turkey working on a construction site, trying to earn some money and to organise my trip to Greece," he says.
But so far, he hasn't found the greater opportunities he had hoped for in Europe.
"If I find any way at all, I want to go to Germany because I know some people there. Maybe I could find a good job," he says. "I would leave as soon as possible if I just found the road and some money to get there.
"I've tried many times to go [illegally] to Italy from Patra, hiding under a truck, but it never worked," he adds.
He says he's tried the official, legal routes for asylum in Greece, which would enable him to live and work legally in the country.
"I've tried to claim asylum but I can't. It's very hard. Many times I've been to [the asylum office] but I never get a meeting. They always say I have to wait."
Using a mobile phone borrowed from a friend, Mahmoud speaks to his family in Iran at least twice a week. He gives them updates on his journey but never tells them the truth about his life in Athens.
"I tell them Athens is a good city, with nice people, but really, it's like someone has injected this city with filth," he says.