The 26-year-old recently rekindled his romance with the actress after she cheated on him with director Rupert Sanders.
"The sex scene in this one is pretty ridiculous as well...you're trying to think of things to make it sexy, it's supposed to be about the greatest vampire sex you've ever had. You try and give a face of ecstasy; guy's faces I don't think are really designed to do that," contactmusic.com quoted Pattinson as saying.
The film is the final installment of the 'Twilight Saga' franchise.
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