He's a notorious ladies' man and has been seen with some of Hollywood's most beautiful women.
But while many may have hoped that John Mayer may have changed his lothario ways since he started dating Katy Perry, reports today are suggesting that this is not the case.
According to Life & Style, the singer has been going behind Perry's back to enjoy "sex dates" with an unidentified woman.
A source told the magazine that he has been seeing this woman since early 2011 and they continue to regularly meet up for illicit trysts whenever they can.
They claimed: "They meet frequently, just for sex dates. And they sext each other almost constantly.
"John and this woman have incredible sexual chemistry and have been seeing each other nonstop since their first encounter almost two years ago."
This will come as a huge blow for Perry, who went public with her relationship with Mayer this month on the red carpet at the A Christmas Story: The Musical on Broadway in New York.
A friend close to the star told the magazine that Katy was "totally into" John and was under the impression that she has reformed his womanising ways.
They added: "She'd be totally devastated if she knew that John was cheating on her."
EntertainmentWise have contact Mayer's rep for comment.