Stylist claims Gossip Girl star kept her as sex slave

Actor Ed Westwick stands accused of being a "violent sexual predator" who repeatedly raped a 20-year-old stylist, holding her captive for two horrifying days at his Hollywood mansion.

Haley Camille Freedman, now 23, is the fourth woman to claim that the Gossip Girl star raped or sexually assaulted her, The Daily Mail reports.

The former art director of the Instagram-based fashion magazine Kat & Bare, Freedman named Westwick in documents filed in Federal court in Los Angeles.

She's suing her ex-partners at Kat & Bare for, among several complaints, breach of contract and fraud, accusing them of "shunning" her and cutting her out of the business she helped build after she decided to go public with her shocking account of her "nightmare" 2014 sexual encounter with the screen heartthrob.

In Freedman's 129-page lawsuit, 30-year-old Westwick - best known for playing womanising bad boy Chuck Bass on Gossip Girl - is described by her lawyers as "monstrous", a "serial rapist," and an "abusive, crazed alcoholic".

Freedman met Westwick at a party on August 5, 2014, after a night out with her friend Ashlynn at Hollywood hotspot 1 Oak, according to the court papers.

"Westwick displayed an immediate attraction to Freedman, flirting with her openly. Freedman responded and the two continued to flirt, escalating to kissing," the papers say.

The two ended up at Westwick's lavish Glendower Estate home where they "soon went to Westwick's bedroom, where they proceeded to have what began as consensual sexual intercourse.

"However, during their first intercourse, Westwick became violent and aggressive, demanding that Freedman strangle him or slap his face and when Freedman declined, putting his hands around her neck and slapping her and strangling her against her will."

Read the full account here.

Westwick has been accused of sexual misconduct by three other women: Rachel Eck, Kristina Cohen and Aurélie Wynn.

In November, Cohen accused Westwick of sexual assault, claiming the star had "held [her] down and raped [her]" after she fell asleep in a bedroom in his house.

Shortly after the claims, Wynn alleged a "similar" ordeal happened to her when she visited Westwick's home with her boyfriend at the time, Mark Salling.

Westwick took to social media to deny the claims.

He wrote: "It is disheartening and sad to me that as a result of two unverified and provably untrue social media claims, there are some in this environment who could ever conclude I have had anything to do with such vile and horrific conduct.

"I have absolutely not, and am cooperating with the authorities so that they can clear my name as soon as possible."

A third woman, Eck, has since claimed Ed had pulled her onto a bed and "aggressively groped [her]" when they were at a party.

She alleged he would "try to kiss me or kind of push me up against the wall", and although she "pushed him off" each time, she claims "it got worse and he got more handsy" as the night wore on.