"We had intimate relations" two or three times the first night, said McGee, who claimed she and the Monster Garage star had a torrid sexual romance for five weeks which included daily texting.
McGee told the magazine that she believed James and Bullock were on the rocks. "I would never have hooked up with him if I thought he was a married man," she told the magazine.
She even claimed to have a pet name for James - "Vanilla Gorilla" - because of his physical gifts.
Bullock won Best Actress for her performance in "Blind Side."
She and James are also enduring a long custody battle with James' ex-wife, former porn star Janine Lindemulder.
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