“I would’ve broken up with him immediately,” the Twilight alum claimed.
She described the dress from Breaking Dawn Part 1 as “the one”.
The Love Lies Bleeding star vented on The Late Show over another daring fashion choice and got bleeped.
The Oscar nominee played Bella Swan in all four films of the Twilight series.
The actor, who played Jacob Black in the saga, said he had to fight to get his spot in the franchise back.
The "Twilight" actor, who dated the pop star back in 2009, says the two are "rekindling" their friendship.
The franchise's "Team Edward" vs. "Team Jacob" rivalry made it difficult for the actors to foster a real-life friendship, he said.
Robert Pattinson and Kristen Stewart became household names thanks to their roles in the vampire romance movies.
"He walked over there, I think, with a stained shirt," director Catherine Hardwicke recalled of Pattinson's early auditions for his breakout role.
The film director has also explained why she stepped away from a remake of The Little Mermaid.