True Mates

Bella has a twin, but this twin was cursed, making her identical to Bella, her name is Roune. No one could tell them apart before. Not even their parents. No their teachers or previous boyfriends. But what happens when they move to Forks and they both read in a book that, if twins are born identical and 1 is cursed, the curse can only be broken by the choosing of a true mate of the Twin that is cursed. So what happens when both twins fall for a Cullen.