Former Happy Days pin-up Scott Baio is set to reveal all about his romances and sex romps with stars like Brooke Shields, Lesley Ann Warren and Melissa Gilbert in a steamy new memoir.

Baio, who played Chachi in the hit TV show and its spin-off Joanie Loves Chachi, battled sex addiction for years and now he's revealing his bedroom secrets with his famous exes.

A publishing source tells the Globe magazine the explosive book will include details about the actor's alleged trysts with Pamela Anderson, Nicollette Sheridan, Denise Richards and Heather Locklear.

"He bedded some of the hottest women in Hollywood back in his day, but he actually confessed that most of his gorgeous girlfriends couldn't satisfy his salacious sexual appetite," the insider says.

Now 50, Baio has conquered his sex addict ways and is happily married to former Playboy Playmate Renee Sloan, the mother of his four-year-old daughter Bailey.