Or is there a plot twist to this tale?

Did vampire hottie Robert Pattinson really pop the big question to one of his sexy 'Twilight' co-stars?

Kristen Stewart -- a.k.a. Bella Swan -- tells People magazine Pattinson did propose to her on the film set. "I mean, I don't know how serious he was, but yes," Stewart says.

But wait, there's a plot twist. "I can't remember proposing to her," Pattinson tells the mag. "It used to be my thing, I would propose all the time," he says, adding: "Just go up to someone, you know, and say 'I love you' or ask them to marry you. It always works."

Pattinson's proposals, it turns out, are little more than a "good conversation starter," the 'Twilight' hunk tells People.