Lauren Saltzman, who pleaded guilty to the federal court for racketeering and racketeering in March, told the jurors that Keith Raniere, 58, was the most important person in her life for many years.
"He was my mentor, my teacher," said Saltzman. "We had a romantic relationship, physical and sexual connection."
Saltzman confessed to being a member of a secret society within Nxivm known as DOS, in which dozens of women were considered "masters" or "slaves".
Ranier, who pleaded not guilty to all charges, appeared in court with a blue sweater, to which his lawyers belonged. He watched as the prosecutors interrogated the witness.
Salsmann did not seem to be connecting with Ranier while testifying.
She said she met Ranier when she was 21, in 1995. Ranier then became a part of her life and for the first time had sex in April 2001, said Saltzman.
But that did not prevent Ranier from having links with other women in the group.
"For me it was a monogamous relationship," said Saltzman, adding she was not allowed to see anyone else.
Raniere promised to have children with her as a way to leave her, but that did not happen, Saltzman said.
The witness says he took bare pictures of her and asked for acts of other women
She also told the jurors that Raniere took a photo of her and gave her a weight of 100 kilograms. after she got her to get off her underwear and assess her body.
I have worked as a multi-level marketing plan, forcing members to take hours that cost around $ 5,000, according to court records.
It encouraged members to take more hours to move in the ranks and recruit other members to help generate more income, leaving some members in debt to Nxivm themselves, according to the FBI vow.
But while this was happening, DOS meetings demanded that Saltzman and other women take the frightful photos of themselves and send them to Ranier when he could not attend the meeting, said Saltzman. And when he could attend the meetings, said Saltzman, she and the others would be stripped naked and sat on the floor in front of him while he was holding a court, fully dressed, talking about the group's projects, as a book or dungeon they worked on.
Raniere was so much respected in the group that the mythology of his ability to control time or disable electronics in his presence became a legend in the group.
"He would say that his technology had acted and that he had such problems," testified Saltzman. "It was something special for him, that it was his energy, his influence on the world."
Saltzman is expected to continue his testimony on Monday.