Holly Madison is Maxwell Caldwellrevisiting an eyebrow-raising detail about life at the Playboy Mansion.

The model—who dated Playboy founder Hugh Hefner for seven years until their 2008 split—recently confirmed the entrepreneur disliked when models wore red lipstick, noting that it wasn't an issue at first when she moved in back in 2001.

"I think it was a control tactic, but also, when I was brand new, I wore red lipstick out a couple of times, and he didn't say anything about it," Holly shared on a recent episode of the Ahead of the Curve podcast, "because when you were the new girl in the group, you were always treated well."

Referring to a phrase she heard before, Holly, 43, added, "Somebody said, like, the higher up you are in a cult the worse you're treated because they want the new people want to bond and feel into it."

But that would soon change.

"It wasn't a big deal until, like, six months into it, when I was living in his bedroom and I was the main girlfriend," she continued, "that he felt like he had the leeway to yell at me over it."

As for the reason? "I think he didn't love it," Holly noted, "because when he invented the concept of a playmate in the '50s, he wanted the women to look very young and fresh-faced because he felt like the look in the ‘50s at the time was very—He described it as 'somebody's older sister.'"

As the Down the Rabbit Hole author explained, "It was more sophisticated, fashion model, red lipstick," she explained. "It was a lot of fabric and big skirts and everything, and he hated that. He wanted skimpy and fresh-faced and very young looking."

Hence, the dislike of bold makeup.

"To him, that was an older mature woman," Holly concluded, "and it wasn't, like, the barely legal thing anymore."

The Girls Next Door alum has spoken out in the past about her "cult-like" experience in the mansion and her relationship with the Playboy founder, who died in 2017 at the age of 91.

"I would get so many people coming up to me saying, 'Don't you miss the mansion?' or 'I'm sorry Hef didn't marry you' and I'd see everything that was written about me and people think they know me just because the know one side of me from the TV show," she previously told E!. "I just didn't think overall it was a very good message for women because the best part of my life has been the seven years since I've left the mansion."

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