On Sunday, Us Weekly spotted the leggy former pro wrestler turned "Dancing With the Stars" hoofer driving through the gates of the commitment-avoiding Oscar winner's Los Angeles-area home.
Come Monday morning, she was apparently still there.
"It's more than just a fling," a source insists to the mag. "They're basically exclusive at this point."
The pair, who have known each other for several years and were set up by a mutual pal, have supposedly rendezvoused in London and at George's expansive villa in Lake Como, Italy.
But another snitch believes that Clooney, 50, and Keibler, 31, are taking an easygoing approach to their purported entanglement.
"It's just fun. It's not as serious as everyone is making it out to be," a Stacy confidant tells OK!. "He thinks she's gorgeous and fun to be around, and she thinks he's George Clooney: smart, hot, talented. He's George Clooney -- there isn't too much more to say than that."
Except maybe this: "It's like asking someone if they wanted to go on a date with their 'dream man' and then having it turn out to be reality," opines the spy. "She's always thought he was a good-looking guy."
But, the mole cautions, "They're not monogamous. It's just hanging out, hooking up. Really low-key and chill."
As for Clooney's most recent ex, Italian model-actress Elisabetta Canalis, she's "taking meetings" in Los Angeles, says the New York Post, which spied her looking "carefree" in leather pants while dining out with some girlfriends.
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