The 40-year-old engaged mother of one is opening up for the first time about how she met the musician, what transpired between them, and why she shared her story with investigators in her upcoming memoir, The Pursuit of Porsha: How I Grew Into My Power and Purpose.
Williams said she met a friend of Kelly's back in 2007 when she was 25 years old. At the time, she was considering a career in music and said she agreed to be flown out to Chicago, Illinois, to meet the star so she could potentially work with him.
She said she expected to be taken to his recording studio but was instead driven to his home, where they exchanged brief hellos.
After that, Porsha said someone led her to his bedroom and left her there alone, where she waited for hours.
When Kelly finally joined her, she said he demanded that she take off her clothes.
"I've already put myself in this position," she writes in her book, according to People. "This is what you're supposed to do. You have to. There is no turning back."
Williams said she saw Kelly two more times after that initial encounter and that she met several young women who were also staying at his house.
She said she made the decision to stop seeing him after she woke up one day to the sounds of a woman being beaten in another room.
The singer's lawyer, Thomas A. Farinella, declined to comment.
Porsha said she had been abused by men prior to Kelly and that she eventually ended up going to authorities to report her experiences with him.
"I realized it was my opportunity to help anyone who's been hurt by him," she told People. "There had been so many other instances where I had been abused by men that my mentality [at that time] was of an abused person, and that it was okay for me to be treated like that."
But it was not something Williams said she was comfortable sharing until many years later. For a long time, she kept it a secret, even from those to whom she's closest.
"It's not something you want to tell your mom, because my mom is a very strong woman and she did her very best in raising me," she explained. "And I think for any woman or man who's been in an abusive situation, you don't want to tell your parents because you don't want them to think that they had let you down in any way. I don't want her to think that she had done anything wrong. And so I took it upon myself."
"But I was glad when I did, she was glad that I told her and we talked about it," she added. "She told me some of her experiences. And we just talked about how this should be told so other women don't have to go through it."
The Pursuit of Porsha: How I Grew Into My Power and Purpose hits bookshelves on Nov. 30.