The Paradise brothel in La Jonquera is Europe's largest. Pere Duran

When police entered her bedroom in the Paradise macrobrothel in La Jonquera (Girona), she showed no signs of relief, joy or sorrow.

"It's like being with a 10-year-old. Pure innocence," says one source from the investigation.

In March, police rescued F. B., a 22-year-old Romanian with severe mental disabilities, from one of the largest brothels in Spain. "It doesn't even take 30 seconds of conversation to realize she's disabled," says the same source.

An organization that supports the reintegration of sex workers first sounded the alarm. They met the young woman two years earlier when she was living in one of the organization's shelters until she decided to leave (she's of legal age, and her disability is still not recognized in Spain).

The brothel manager alleged that they had taken her in because she was being beaten up in the street

While conducting rounds attending to prostitutes in the street, volunteers from the organization spotted her at a roundabout in La Jonquera. "Are you okay?" they asked.

Her response was evasive. "I can't tell you right now," she said, and walked away.

The organization then alerted police, who launched a several-month-long investigation that culminated in the girl's rescue and the arrest of her mother, who had forced her to prostitute herself since the age of 18, as well as the pimp.

F. B.'s life has been filled with trials and tribulations. Originally from Romania, she lived under the tutelage of the government until she was two because her mother could not take care of her. Moreover, she experienced a number of health problems. She suffered from stunted growth and two episodes of meningitis - at six and 14 - according to case sources. She was then admitted to a special education center in Bucharest, where she studied until she moved with her mother to Terrassa at 17. At 18, her mother began to exploit her sexually, police say.

F.B.'s first assignment was a club called Las Palomas, where the mother also worked as a prostitute and controlled a network of women. "Everyone there knew about her disability," confirms one source.

In the mother's apartment, agents found various documents showing that F.B. had transferred money to her mother, giving her a portion of the salary she earned as a prostitute.

Over the course of four years, F.B. sold her body for money in Terrassa, private homes, on the streets of Barcelona's Raval neighborhood, on Madrid's Montera street and abroad in Cyprus and Malta, according to sources familiar with the case.

When she was found in Paradise, the manager of the brothel alleged that they had taken her in because she was being beaten up in the street. But agents could see that she had also been prostituted since arriving at the megabrothel.

F. B. is currently staying in one of the shelters of the organization that found her, and steps are being taken so that public prosecutors address her disability.