After vague claims against Paul Marciano, Kate Upton detailed the Guess co-founders alleged assault.

The 25-year-old model claims that Marciano approached her during her first Guess lingerie modeling campaign in 2010, when she was just 18 years old.

As soon as I walked in with photographer Yu Tsai, Paul came straight up to me, forcibly grabbed my breasts and started feeling them playing with them actually, Upton told Time. After I pushed him away, he said, Im making sure theyre real.

Marciano then allegedly grabbed Uptons thighs, arms and shoulders to keep her closer and tried to dismiss Yu Tsai from the room. Upton refused.

Kate Upton accuses Guess exec Paul Marciano of sexual harassment

Then Paul insisted that he walk me up to my hotel room. I immediately declined. The only thing I was thinking is if he touches me like that in public, I cant imagine what hed try to do in private, she told Time.

Thankfully, Yu Tsai stepped in and insisted hed do it. I was so relieved and felt like I had barely escaped.

A month later, Upton claims, Marciano made the same proposition. After denying him, she was fired from the Guess shoot, she told Time.

Yu Tsai was fired in late 2010, at which point the model began to work with photographer Ellen von Unwerth.

Guess exec Paul Marciano denies Kate Uptons harassment claims

Pauls behaviors became much more aggressive without Yu Tsai there as a buffer, Upton said.

She continued rejecting Marciano until she eventually stopped working with Guess in May 2011.

(Marciano) said I was disgusting and started telling people how unprofessional I was by spreading rumors that I was drunk on set and partying every night, which of course I wasnt. I was then told to leave because Paul had said, Get that fat pig off my set, she told Time.

Upton, who has since gone on to wild success with Sports Illustrated, said Marcianos alleged assault almost forced her to quit modeling and took a huge toll on my confidence and self-worth.

A #MeToo NYFW show is letting models speak up about abuse

She first broached the alleged assault on social media in late January.

“It’s disappointing that such an iconic women’s brand @GUESS is still empowering Paul Marciano as their creative director #MeToo,” she tweeted. “He shouldn’t be allowed to use his power in the industry to sexually and emotionally harass women.

Marciano denied the allegations at the time and again on Wednesday, calling them absolutely false and preposterous.

I have never been alone with Kate Upton. I have never touched her inappropriately. Nor would I ever refer to a Guess model in such a derogatory manner, he told Time.

I fully support the #MeToo movement. At the same time, I will not allow others to defame me and tarnish my reputation. I have pledged to Guess and its Board of Directors my full support and cooperation with a fair and impartial investigation.

Guess did not immediately return a request for comment.