Five hundred US Dollars. That's all it took for 46-year-old El Hadj Souleymane Naroua from Niger to buy the life of Hadijatou Mani (pictured), a 12-year-old girl.
Hadijatou's story and 10 others feature in a report produced by Anti-Slavery International into Niger's Wahaya - or 'fifth wife' - culture. The fifth wife is the unofficial wife who acts as a slave to the family.
Sarah Mathewson from Anti-Slavery International takes up Hadijatou's story: "El Hadj already had four wives and then seven other 'fifth wives', so Hadijatou became another 'fifth wife', also known as Wahaya. She would do domestic and agricultural work and was never paid or given any kind of benefits.
"She was first raped when she was 13 and she was often beaten and raped as part of the Wahaya role. She had four children but only two survived."
Wahaya are girls and women of slave descent who are sold by their masters to be 'fifth wives' to other men. "The status of slave is passed down from generation to generation and it's become a kind of social class," says Sarah.
Measuring the extent of the Wahaya problem is difficult because it's hidden away, but Anti-Slavery International's report estimates there are thousands of them. By interviewing more than 150 Wahaya, they also found that 83 per cent are sold before their 15th birthday.
Wahaya are seen as a sign of prestige and many men have more than one. But when Hadijatou's story took an unexpected turn, attitudes started to change.
In 2005, Timidria - a local partner of Anti-Slavery International - began a campaign to promote the new law against slavery in Niger, which was passed in 2003. Timidria's campaign started a chain of events that would lead to Hadijatou becoming a beacon of hope for Wahaya girls.
"El Hadj decided to marry her legally to avoid falling foul of the law," explains Sarah. "But Hadijatou understood this to mean she was being freed, so she took her certificate and escaped with the help of her brother."
After escaping, Hadijatou remarried and had another child, but it wasn't long before El Hadj found her.
"He filed a complaint with the local police and that meant charges of bigamy being brought against her," says Sarah. "He even laid claim to her new baby because, under customary law, any baby she would have as his slave also belongs to him."
In May 2007 the local court sentenced Hadijatou, her new husband and her brother to six months in prison. She was also fined for bigamy. Anti-Slavery International and Timidria both provided legal assistance, arguing that the Niger government had failed to implement its own laws.
Eventually, in 2008, the court ruled against the state of Niger for failing to protect Hadijatou from slavery. She was compensated with 10m CFA francs - the equivalent of about £12,000.
"That was a massive success and such a liberating experience for her," says Sarah. "Everyone knew what had happened, people were afraid. The slave owners were afraid and they stopped selling these girls into the Wahaya practice."
But there is still a long way to go to make Wahaya a thing of the past.
"We hear reports every so often of more cases and it seems that the big institutions are not looking at this," says Sarah. "Recently the international attention has dropped off, we haven't seen journalists coming and we haven't seen national reporting of the issue."
Hadijatou's journey is not over either. She is still battling in the courts for the return of the two children she had to leave behind when she escaped. "In her local area they have started selling young girls again," Sarah cautions.
Anti-Slavery International's report outlines 10 action points to ensure that Hadijatou's victory is not an isolated one.
"If we maintain a high level of international scrutiny, both at the government level and at the local level, people won't be able to get away with it any more," says Sarah. "The government has introduced specific anti-trafficking legislation, which is great. Implementation is now the big challenge."
Read Anti-Slavery International's report into domestic and sexual slavery in Niger
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