Will Robert Pattinson & Kristen Stewart's relationship ruin 'Twilight'?

As Robert Pattinson and Kristen Stewart filmed their intense, romantic scenes as lovers Edward Cullen and Bella Swan in 'Twilight,' they began to fall for each other offscreen.

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That makes perfect sense, according to their castmate Ashley Greene. "I get little crushes on a lot of people who I work with," Ashley, who plays Alice Cullen, told Life & Style at Rock & Republic's Robertson store opening on June 11 in LA. "You have to make yourself believe there's something about them that you love."

But now that Rob, 23, has successfully wooed Kristen, 19, away from her boyfriend Michael Angarano, one insider wonders where their relationship will go. "For Rob, half the attraction with Kristen was the chase," the insider reveals. "He pursued her so heavily -- being a crazy romantic, proposing marriage and everything. Now that Rob's with her, it's just anticlimactic."

If Rob loses interest, it could have a major negative impact on the next three movies in the Twilight series, New Moon, Eclipse and Breaking Dawn . "People are just so enamored with the connection that they portray on-screen. If they failed to do that in the second and third ones, I think we'd be in trouble," Ashley says. "They're great on-screen, and obviously they get along," Ashley tells Life & Style. "But maybe they should just not be a couple until after the fourth movie, 'Breaking Dawn.'"

THE STARS OF 'TWILIGHT' TALK EXCLUSIVELY TO TERRA

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