They often fled their homelands to escape sexual abuse - but for many asylum seekers, it continues in the UK. Fear of deportation typically means they don't tell police, but one effect of the Harvey Weinstein revelations is that they have now begun to talk about their experiences among themselves.
At the age of 37, Grace has never had consensual sex.
"I am not the only one. There are many more women like me," she says, hunched over and looking down at the table. She indicates to the wall that separates the small meeting room from her friends in the adjacent room.
"We are the most destitute and vulnerable women in the UK."
To her it makes sense that destitution and exploitation go hand in hand - it's happened all her life.
Grace arrived in London at the age of 17, back in 1998. She was born in West Africa, but doesn't want to reveal the country for fear of endangering her relatives.
"I came from a very, very poor family," she tells me.
So poor that at the age of 15, Grace and her 17-year-old-sister were both married off to a man older than their father - in exchange for a dowry. They moved into a palatial house in the capital city with his five other wives.
For the first time the sisters didn't have to worry about their next meal, but that was the only thing they didn't have to worry about.
"It wasn't a good life. I suffered a lot," she says. It quickly becomes clear this is a massive understatement.
Grace and her sister were subjected to continuous physical, verbal and sexual abuse by their husband. They were also made to take part in superstitious ritual ceremonies that he believed would advance his political career - including drinking animal blood, she says with a shudder.
The young women relied on each other for support, afraid that if they spoke out their family would be harmed.
"Our husband was a powerful man," Grace says.
After two years of marriage, Grace and her sister reached breaking point. They confided in a sympathetic uncle who said he would help them leave the country - it would be assumed that they had run away, he said, and no-one would admit to having helped them. He arranged short-stay visas, took them to the airport and presented them with one-way tickets to London.
The uncle had an old friend who would pick them up from Heathrow airport, he told his nieces. A good man who would take care of them.
"When we arrived at the airport there was a man standing there holding up a sign with our names," says Grace. "He looked like death standing up."
Their uncle's friend was suffering from cancer. He hadn't revealed this before, he said, because he was keen to do a favour for his friend and to provide the sisters with temporary sanctuary.
He told Grace and her sister, who were now 17 and 19, that his cancer was terminal, and that as he was not a wealthy man he wouldn't be able to provide for them after his death. Instead he would introduce them to friends at his local church, mostly other West African immigrants, who would help them with accommodation.
He died three weeks later, and as he had predicted, Grace and her sister - who had no legal right to work in the UK - moved in with families they met through the church.
"Migrant families in this country, who are themselves poor and working long hours look for young, single women to look after the children and do the cooking and household chores," says Grace. "My sister and I moved in with different families. We were reliant on them for food, clothes. For everything."
Grace didn't have her own room. She slept on the sofa in the living room, waiting until everyone in the family was ready for bed before getting any rest herself. She had little privacy and made sure not to disturb the family.
She soon discovered how unsafe she was.
"The man of the house would come down at night when everyone was asleep. He began using me for sexual pleasure," she says. "He knew I was destitute and had nowhere to go. I knew nothing about the legal system then. I couldn't go to the police because I was scared I will be detained or deported. I was at his mercy. He would say, 'Who are you going to tell?'
"I couldn't talk to his wife about it. I was worried that if she didn't believe me she would throw me out of the house. What could I do in my situation? I'd look outside. London always seemed liked it was winter, and I'd think, 'What can I do? Nothing.'"
Her sister, Grace learned, was in a similar situation. They were both trapped. But there were bigger problems ahead.
When the family's children grew to school age, Grace was informed that she was no longer needed and that she would have to leave. While waiting for another family from the church to take her, and relying on friends for odd meals, Grace slept on park benches and on night buses.
She has lived in more than a dozen homes during 20 years in the UK and in nearly all she has been sexually abused.
And the sexual abuse has continued from one family to the next.
"I slept on floors and sofas. If there were male overnight visitors I would almost always be violated by them. Often men would come to my room at night and they would touch me. Or more.
"At night I would try and jam the door with drawers to try and stop the men getting in. Sometimes it worked, sometimes it didn't. In the morning in front of their wife and children they acted like nothing had happened.
"This didn't happen just once or twice with one or two families. It happened many, many times."
In 2008, a tragedy occurred. Grace's sister had been talking to a man she had met on an internet chatroom. She told Grace that she would be going to meet him.
She didn't return.
"I was in hell," Grace says.
She called hospitals and asked friends who had a more secure status in the UK to go to the police to file a missing person's report. So far, no information has emerged. Grace has not heard from her sister in 10 years.
Feeling more alone than ever, Grace continued shuffling between families and homes, until five years ago when once again a family told her they would no longer need her services. And this time no other families came forward with an offer of work.
"I was homeless. For weeks I was sleeping on park benches or, if I was scared of being alone, I would go on to a night bus and ride all night.
"I'd spend the day begging for change or go sit in libraries or in parks."
Then one day, Grace says, a miracle occurred.
"A man came up to me in the park. I'd met him when I first moved to the UK. He said 'You've aged, Grace.' I said, 'Yes, I know.'
"Then he said, 'There are people who can help you Grace.' I said, 'I'm a slave, who can help me?' He said, 'There are places and people who will help. I will take you somewhere.'"
He took her to a central London refugee centre, where staff listened carefully to her story and offered help to solve her problems.
It was a typical cold October day in London when Marchu Girma stood in front of a room of 35 sub-Saharan African asylum seekers, including Grace, and told about them the news that had been making headlines around the world.
Numerous household-name actresses had stepped forward to accuse the Hollywood producer Harvey Weinstein of being a sexual predator. The story achieved the rare combination of going viral on social media, and dominating both mainstream news coverage and dining-table chatter. Thousands of women - from all professions - shared their own tales of abuse and harassment they had faced at the hands of powerful men. They used the hashtag #MeToo.
"I remember the moment in the classroom when I told the women about Me Too," says Girma. "It was an 'oh' moment. There was a sudden realisation that they weren't alone. There was a sudden realisation in the room that sexual harassment had even happened to white, powerful, famous and important women.
"It was no longer a shameful secret they had to keep to themselves."
Girma is the grassroots director for Women For Refugee Women, a small organisation for women seeking asylum in the UK. Originally from Ethiopia, Girma herself went through the UK asylum process at the age of 11.
"Women find us through word of mouth," she says. "They tell each other about Women For Refugee Women at church, at detention centres, through other charities. This is a protected and private space for them. All the women that come to us are within the system, they are part of the legal asylum-seeking process. They're looking for solidarity."
Once a week the women come seeking advice, lunch and classes such as English, craft, drama and empowerment.
It was at an empowerment class that Girma told them about Me Too.
Then, for the first time, the women talked about the abuse they had suffered. Many said that sexual harassment was not just something they fled in the countries of origin, but a reality of their life here in the UK.
One woman described a time she cleaned a house for a client who ordered her to strip to her underwear first. Others, like Grace, had stories of sexual violence within their informal living arrangements.
"The asylum process is flawed and works against a victim of sexual harassment or abuse at many stages," says Girma.
"If you don't have legal status you are not considered a person in the eyes of the law. You are not really a human being.
"These women have endured a prolonged and continual cycle of abuse - fleeing sexual violence and walking straight into a life of abuse while in the UK."
The situation is worst for those who are living in the country without having applied for asylum.
"Currently there is data-sharing between police and UK immigration officers and we have heard of cases where women go to report abuse and are held in detention centres or even deported back to the countries they came from, and the deadly situations they were trying to escape. The current system prevents these women from reporting sexual violence and the predators know this," Girma says.
According to the Oxford Migration Observatory there are hundreds of thousands of undocumented or "irregular" migrants in the UK.
But even women who have applied for asylum and have legal status in the UK may be unsure of their rights, says Girma, and hesitant to approach police.
It's been 10 years but Grace's friend, Yanelle, still dreams about the worst night of her life.
A political dissident in West Africa, she was arrested, thrown in prison and then gang-raped at gunpoint by a group of police officers.
After she was released, friends within her political party helped her come to London. She moved in with friends initially, then found work through families at a local church.
Like Grace, Yanelle received a roof over her head and food in exchange for childcare and cleaning.
She filed immediately for refugee status, but received bad legal advice and her first application was declined.
Yet Yanelle was luckier than Grace, she says.
Her landlords may have groped her, but they did not coerce her into having sex.
When one said, "What are you going to do? Who are you going to tell? If I did something and you report me, the police will detain you and send you back," she didn't consider it sexual harassment.
It wasn't until years later, when she had worked and lived with many other families, and had repelled dozens more advances by other landlords, that her thinking changed. And this happened that day in October, when she and Grace sat in the empowerment class at Women For Refugee Women, hearing stories about Hollywood actresses speaking out.
Maybe a man making persistent advances without her consent and touching her body wasn't something to dismiss as insignificant, she thought.
"We never talked about the abuse before Me Too. From the culture I come from it is not common to discuss sexual harassment so freely. But when we saw important women speaking out it changed our mentality. We learned that we all had some experience of harassment," Yanelle says.
"It does seem like we, as women, are at a moment in history where real global change is possible. It's important that this change is extended to the most vulnerable women in our societies," says Marchu Girma,
"We need collective will, and the sisterhood and solidarity must reach down here to women like Grace and Yanelle too."
At the age of 37, Grace has ambitions to pass her GCSEs. She wants to help people. She hopes she can qualify as a midwife. She now lives with a "lovely couple" in their 80s with whom she was housed through a refugee-hosting programme. She still has no legal right to work in the UK and no income. She gets her meals from a food bank and wears donated clothes.
She hopes she will one day find her sister. She also hopes that she will soon receive asylum - she has made three applications since 2013 without receiving a final refusal, and is now on her fourth. The difficulty is proving that she has been in the country for 20 years, because she has no paperwork.
But she's hopeful. She has friends who she can talk to - and they listen, she says.
Yanelle is also re-applying for refugee status. She still dreams about the gang-rape in the police cell in West Africa, but since she heard about Me Too, she shouts back at the rapists and tells them to leave her alone. Sometimes they back away and leave her cell. Sometimes, in her dreams, they don't rape her at all.
Photos by Emma Lynch
All names have been changed
Follow Megha Mohan on Twitter @meghamohan