Oh, it’s a real Public Affair! Jessica Simpson’s friends are saying that the pop sensation felt “betrayed” when her then-boyfriend, John Mayer, 42, made out with Perez Hilton.

Gossip blogger Hilton wrote about the escapade in his new memoir, TMI: My Life in Scandal, where he claims he ran into the two singers while at a New York night club with Christina Aguilera — and that Mayer initiated the kiss!

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Hilton, 42, claims that Mayer also confessed he has a penchant for watching gay porn, even naming his favorite adult star — Brent Corrigan. “He really turns me on,” Hilton recalled Mayer saying before sticking his tongue down Hilton’s throat.

Hilton noted that the “Gravity” singer seemed satisfied with himself, while Simpson “didn’t seem to know whether she was incredibly embarrassed or really turned on.”

An old friend of Simpson’s told Page Six that there was more to the story. What made the incident so shocking, was at the time, Simpson was in an all-out war with the gossip maven. Hilton would refer to Simpson as “Jessica Simpleton” routinely on his popular blog — which infuriated the singer — and referred to her little sister Ashlee Simpson as “Asslee.”

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“Her friends were horrified,” the pal told the outlet, referencing the scandalous kiss. “But [Jessica] didn’t care. John couldn’t do anything wrong, as far as she was concerned. She was absolutely head-over-heels in love with him.”

Mayer and Simpson had a famously off-again, on-again relationship, which the “A Public Affair” singer detailed in her own memoir, Open Book, calling their relationship “toxic.” The pop star also said that Mayer was “obsessed” with her both “sexually and emotionally.”

The 40-year-old singer detailed how the relationship took a toll on her well-being. “I constantly worried that I wasn’t smart enough for him,” she wrote in the book. “He was so clever and treated conversation like a friendly competition that he had to win.” Simpson also wrote how she was so afraid of disappointing Mayer, that she even had a friend check her texts for grammar and spelling errors. “My anxiety would spike and I would pour another drink. It was the start of me relying on alcohol to mask my nerves.”

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The controversial duo eventually called it quits in 2007. Simpson met Eric Johnson in 2010 when a mutual friend invited the former NFL star over to Simpson’s house for a party. The loving couple got married in July 2014 and share three beautiful children together: daughters Maxwell and Birdie, as well as son, Ace.

As far as we know, Mayer is currently single, he has been reportedly linked to Katy Perry, Taylor Swift and Jennifer Aniston since his breakup from Simpson.

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