Of all the types of performer who might refuse an on-camera kiss, musicians make the most sense to us. They're not really actors - they're just occasionally required to act for the sake of a music video. Leona Lewis was asked to kiss Chace Crawford of 'Gossip Girl' fame when she was filming the video for 'I Will Be,' but Lewis had other ideas.
At the time of filming, Lewis had a boyfriend. As she didn't consider herself to be an actor - or have any aspirations of becoming one - she felt it inappropriate to put herself in a lip lock with Crawford. She considered it to be cheating, and asked the director to think of another way around it. Lewis must be a woman of considerable willpower - we can think of many people who'd give anything for a moment of passion with Crawford, and some of them are married!