(Queerty informs us:)
"Not many people know this, but before Robert Pattinson achieved world fame as a deadpan vampire in the Twilight series, he masturbated to the thought of gay sex on the set of a 2008 Spanish film called Little Ashes.
"We [Queerty] always knew Pattinson was hard up for male-on-male contact, but he confirmed this fact in the September issue of Germany Interview. 'My orgasm face is recorded for eternity,' he said, assuring that the gay sex scenes he filmed in Little Ashes were totally authentic because he was hard and euphoric. Faking it 'just doesn’t work, so I pleasured myself in front of the camera.'"