Smitten Ginger Lynn Allen has boasted about the wild nights she says she spent with George after his marriage to actress Talia Balsam, 55, hit the rocks.
Now the blonde plans to fly out to Venice to remind George's new bride Amal Alamuddin that she'll always be there in the background.
Last night stunning Brit Amal, 36, looked unfazed by the news as she touched down in Italy for her lavish nuptials.
The human rights lawyer and her Hollywood fiancé have splashed thousands on security to keep unwanted guests away from their big day.
Meanwhile former porn star Ginger - bragged that George, 53, was an "11" in bed and is the "manliest man" she's ever met.
She said: "On a scale of 1 to 10, I'm going to give George an 11 for performance. And as far as equipment, I give him a 12.
"I never thought he'd get married! I always thought of him as a man's man who played poker and smoked cigars."
But the 51-year-old told US showbiz website radaronline: "I spent the night at George's house many times.
"George must have been separated and didn't want to let me know. "
Allen revealed she first met the Gravity star on the set of short-lived cop series Sunset Beach in the early 1990s.
She described their chemistry as an "instant fire" that sparked a "wild rendezvous" and some steamy sessions between the sheets.
Clooney has since admitted he was not ready for marriage when he tied the knot with Talia, who is now married to Mad Men star John Slattery, 52.
He said: "I probably, definitely wasn't someone who should have been married at that point. I just don't feel like I gave Talia a fair shot."
The actor is expected to tie the knot with Amal at the Aman Canal Grande Venice hotel on Saturday morning.
