"If we go out in public, every little detail is scrutinized," she says of her hunky costar

Kristen Stewart may be completely enamored with her undead boyfriend in Twilight, but the actress insists her intense romance with costar Robert Pattinson is reserved for the big screen.

“Rob and I are good friends. We went through a lot together, so we feel very close,” the newly-minted It-girl says of her sexy costar in Nylon magazine’s March issue.

Stewart has been dating actor Michael Angarano since 2006, but that hasn’t stopped rumors of an off-screen fling with her Twilight costar.

“If we go out in public, every little detail is scrutinized, like the way I stand next to him. And it s like, I know this guy really [expletive] well,” she says. “It’s only natural that we’re sort of leaning on each other, because we’re put in the most psychotic situations.”

Stewart and Pattinson will reprise their roles in the Twilight sequel, New Moon, which begins filming in March and is set to open on November 20, 2009. The third film in the series, Eclipse, will arrive June 30, 2010.