From bestiality to unprotected group sex, here are the biggest bombshell allegations made about Hugh Hefner and Playboy magazine on 'Secrets of Playboy'

Madison said on an early episode of "Secrets of Playboy" that she thought it was "really gross" that Hefner "didn't want to use protection" during group sex with her and other women at the Playboy mansion in Los Angeles.

The reality star, who lived with Hefner at the mansion as one of his main girlfriends from 2001 to 2008 and appeared with him on the E! reality show "The Girls Next Door," went on to describe the first time she had sex with Hefner and other women, after they all returned to the mansion from a night out.

"There was definitely no romance or seduction or anything like that. It was dark in the room, but there was a giant movie screen of porn in front of the bed," Madison said. "He was in the middle of the bed and then the women were surrounding him."

"It was all very mechanical and robotic, and you would kind of follow the other women's lead," she added. "The impact it had on me was so heavy. I never expected to be the first person to have sex that night or to be pushed into it."

Hefner's other ex-girlfriends, twin sisters Karissa and Kristina Shannon, reiterated the same during the March 28 episode of "Secrets of Playboy."

"The problem is, Hef doesn't like to use protection," Kristina said. "From the butlers, we'd just order a big bowl and we'd put hot water in it. Then, we'd put rags in it. So whoever was having intercourse with him, when they were finished, they can wipe him off. And then the other girl could do it."

Karissa also compared sex with the Playboy founder to "rape."

The reality star said in the docuseries that Hefner referred to Quaaludes — the brand name for a prescription sedative that became a popular recreational drug during the 1970s and '80s — as "thigh-openers."

"We went out to a nightclub, I was sitting next to Hef, and he leaned over and he asked if I wanted to take a Quaalude," Madison recalled on an earlier episode of "Secrets of Playboy." "I said something like no, I don't do drugs."

According to Madison, Hefner told her that he "typically" didn't do Quaaludes either.

"I just thought it was really weird," Madison remembered.

She went on to explain that she "drank a lot" that first night out due to nerves, and ended up going back to the mansion with Hefner and the other women, where she and the Playboy founder later had sex.

"When I first arrived, it seemed like most of the women who were coming through and testing for Playmate felt like they had to sleep with him to get Playmate of the Year," Madison recalled on the docuseries. "Not every single one of them did; there were a few exceptions, but I think a lot of people felt like they had to."

Several other women featured in the same episode seemed to corroborate Madison's account.

"I think it was known that they were sort of expected to," said Jennifer Saginor, the daughter of Hefner's personal doctor at the mansion and the author of a tell-all memoir called "Playground."

PJ Masten, who was a Playboy Bunny and a Bunny mother from 1972 to 1982, made a similar statement.

"In order to get Playmate of the Year, you had to do some pretty wild things up in the bedroom with Hefner and his friends," Masten said in the episode. "You had to vie for that position."

"The girls did a lot to win that favor, and [Hefner] knew that they would, so he usually played that up," Sondra Theodore, who dated Hefner from 1976 to 1981, said in another interview.

Theodore lived with Hefner at the Playboy mansion in Los Angeles during the time they dated.

"I walked in once and he was ... to my dog, to our dog," Theodore, now 65, said on a previous episode of the docuseries. "I was like, 'What are you doing?' He says, 'Well, dogs have needs.' And I said, 'Stop that.'"

She added: "I never left him alone with the dog again. I couldn't believe what I was seeing."

According to several Playmates and one of Hefner's ex-girlfriends, the routine weigh-ins to ensure the women living at the mansion stayed at what Playboy deemed "that perfect weight," had negative effects on their physical and mental health.

"By the time I was 20, I weighed 90 pounds," said former Playmate Susie Krabacher on a March episode of "Secrets of Playboy."

According to Krabacher, she occasionally did cocaine to "stay thin" when she worked for Playboy, and later ended up in the hospital.

"It was really hard, and it took a lot of therapy to go back to regular eating," Krabacher added.

Theodore added that "a lot of girls" at the mansion were "fresh off the farm."

"They felt like they made it, and yet those same girls, months later, would go home a skeleton," she recalled. "Just a mere shadow of themselves."

Theodore even pointed to a 1977 photo of herself (taken while she was living with Hefner) as proof of the extreme toll life at the Playboy mansion took on her.

"I was skin and bones," Theodore said of herself in the photo.

"He had tapes on everybody," Theodore said in a March episode of the docuseries.

According to Theodore, when she first noticed that Hefner was recording their sexual activities during her time at the Playboy mansion, she was immediately taken aback and asked him what was happening.

"When we started bringing other people into the bedroom, some girls had the same reaction. And he would [say], 'Oh, I can turn it off. If it's not okay, I can turn it off,'" Theodore recalled.

She said that when other women, who were participating in orgies with Hefner and Theodore, asked Hefner to stop filming, he would adjust something on the camera and tell them that it wasn't recording anymore — and that the real-time footage still appearing on the TV screens in the bedroom was only so they could "see" what was going on.

But Theodore alleged that the magazine mogul was still actually recording his sexual encounters, despite what he told the other participants.

"Maybe a week later, a couple days later, all of a sudden, there's the tape," Theodore recalled.

In "Secrets of Playboy" interviews, twins Karissa and Kristina Shannon said they were 18 when they met Hefner after being recruited to do a test shoot for Playboy magazine.

Shortly thereafter, they were named Playmates for July and August 2009, and they received an invitation from Hefner to move into the Playboy mansion in 2008.

When the women arrived at the mansion, they said they learned sex with Hefner was expected of them if they wanted to be his "girlfriends," even though Hefner didn't like to use condoms.

During a routine blood test in preparation for plastic surgery, Karissa said she discovered she was pregnant with Hefner's child but decided not to tell the Playboy founder or anyone else at the mansion.

"I didn't want him to know that I was pregnant. I didn't want him to want me to have it," Karissa said of her reaction to her pregnancy. "I didn't want to be stuck even more inside that bubble. I think it's a way for him to control me even more, have me on a leash."

The "Girls Next Door" star said she ultimately decided to have an abortion but that because of the secretive nature of her pregnancy, Kristina couldn't accompany her sister to the clinic for fear of garnering media attention.

Looking back on her abortion, Karissa said she "100%" made the decision that was best for her, especially given how she felt about sex with Hefner.

"Every time I've done it with him, it's assault," Karissa said of intercourse with the magazine editor. "To me, it's like rape. He used control mechanisms completely through everything, so I'm happy that I had the abortion."

In a statement at the end of each episode, "Secrets of Playboy" says that "the vast majority of allegations have not been the subject of criminal investigations or charges, and they do not constitute proof of guilt."

In a previous statement to Insider about the docuseries and subsequent allegations against Hefner, a representative for Playboy said, "The Hefner family is no longer associated with Playboy, and today's Playboy is not Hugh Hefner's Playboy."

Directly addressing "Secrets of Playboy," the statement added: "We trust and validate these women and their stories and we strongly support those individuals who have come forward to share their experiences. As a brand with sex-positivity at its core, we believe safety, security, and accountability are paramount."

It added: "The most important thing we can do right now is actively listen and learn from their experiences. Today, our organization is run by a workforce that is more than 80% female and we will continue to confront any parts of our legacy that do not reflect our values today, and to build upon the progress we have made as we evolve as a company so we can drive positive change for our employees and our communities."

Hefner died of natural causes in 2017. He was 91.

Representatives for Hefner's estate didn't immediately respond to Insider's previous requests for comment on allegations made in "Secrets of Playboy," which takes a closer look at the men's magazine and the life of its founder.

Before the show's premiere in January, Hefner's son Cooper tweeted a statement in which he called his father "generous in nature" and someone who "cared deeply for people."

"These salacious stories are a case study of regret becoming revenge," Cooper added in the tweet.