Make that friends who get super sexy together on-screen. At one point, Deli even licks Bieber's abs. But that's all in a day's work for the Victoria's Secret model.
"This is a job," she says, but "it was so much fun because he is such a nice guy, and he was making everything easy."
In their two days together on set, Deli says she saw no signs of Bieber's bad boy image. "Oh my gosh, he is different than we see him in the videos, or interviews or pictures," she says. "He is a gentleman. For me, it's very important and what I appreciate in men -- it doesn't matter how old you are, how much money that you get, what is your job, you have to be respectful to a woman and this is how Justin is."
And that includes his sensitive side -- Deli says she "just wanted to give him a huge hug" during that on-stage breakdown on Sunday.