The 85-year-old Playboy boss – who split from fiancee Crystal Harris earlier this month, and shortly after moved Anna into his bedroom – thinks his new girlfriend is "one in a million".
Writing on his twitter page, he said: "With Crystal gone, Anna is my best girl, but she's also Crystal's good friend. Anna is really one in a million. (sic)"
Despite having moved on with the blonde beauty – who was named Playmate of the Month for January 2011 – the magazine mogul admitted he was stunned by Crystal's decision to call off their wedding days before they were due to tie the knot, but admitted the support of Anna was helping him through the split.
He recently tweeted: "I didn't see any of this coming, but I'm glad things went wrong before the marriage instead of after. Live & learn.
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"The one who has been the most supportive is Anna. She didn't see this coming either, she's Crystal's best friend. (sic)"
Meanwhile, Crystal blamed the couple's split on her not feeling comfortable to know that Hugh had other women in his life.
She said: "I wasn't the only woman in Hef's life. I didn't feel comfortable in my heart knowing that and getting married to him, because a marriage is between two people. That's not what our relationship was."