Armie Hammer's former girlfriend Paige Lorenze felt "unsafe" with the actor.
The 23-year-old student started dating the "Call Me By Your Name" star last September but broke things off with the 34-year-old actor when he "started making rules" for her.
She recalled to Vanity Fair magazine: "He started making rules for me of things I could and couldn't do, who I could have over, who I couldn't. He told me that I couldn't have anyone else in my bed.
"And then I just started to feel really unsafe and really sick to my stomach about things.
"I was also emotionally dependent on him."
Lorenze decided to end their relationship over text because she was worried about Hammer's unpredictability.
She said: "You never know what you're going to get with him—he's kind of a scary person."
Alarm bells had rang for Lorenze shortly after she met the "Rebecca" actor and he quickly confided in her some "dark" family secrets.
She said: "A lot of really dark stuff. I felt confused why he was telling me this stuff so instantly...It was stuff I would never share off the bat...
"He said his grandfather was this kind of very scary person who had these crazy sex parties where there would be guns.
"He thought it was cool and was proud of him in a way."
During their time together, Lorenze claimed she had to pay for "everything" because Hammer didn't have any money and was getting by on loans from friends.
Another of Hammer's former girlfriends, Courtney Vucekovich, also spoke to the publication about her three-month romance with the "Lone Ranger" star, who she bonded with "over past trauma".
The 30-year-old beauty said he initially made her feel like "the only girl in the world" but she was left uncomfortable after one sexual encounter in which the actor allegedly persuaded her into "a bondage scenario that [she] was not comfortable with".
Vucekovich said she "eventually consented and really regretted doing so", and after they split last September, she checked herself into a treatment programme for trauma.
Andrew Brettler, Hammer's lawyer, insisted everything between the "Man From U.N.C.L.E." star - who has children Harper, 6, and Ford, 4, with estranged wife Elizabeth Chambers - and his former partners was "consensual".
He told Vanity Fair in a statement: "All interactions between Mr Hammer and his former partners were consensual. They were fully discussed, agreed upon in advance with his partners, and mutually participatory.
"The stories perpetuated on social media were designed to be salacious in an effort to harm Mr Hammer, but that does not make them true."
An Instagram account called House of Effie first sparked reports about Hammer's alleged sexual behaviour when they posted a series of unverified direct messages allegedly from the actor, which referenced cannibalistic fantasies.
Following the scandal, Hammer left his upcoming film "Shotgun Wedding" - which also stars Jennifer Lopez - because he didn't want to be away from his children amid the "vicious and spurious online attacks".
He said: "I'm not responding to these bulls*** claims but in light of the vicious and spurious online attacks against me, I cannot in good conscience now leave my children for 4 months to shoot a film in the Dominican Republic. Lionsgate is supporting me in this, and I'm grateful to them for that."
SEXUAL HARM - DO YOU NEED HELP?
If it's an emergency and you feel that you or someone else is at risk, call 111.
If you've ever experienced sexual assault or abuse and need to talk to someone contact Safe to Talk confidentially:
• Call 0800 044 334
• Text 4334
• Email firstname.lastname@example.org
• For more info or to web chat visit www.safetotalk.nz
Alternatively contact your local police station - click here for a list.
If you have been abused, remember it's not your fault.