Twilight by Evangelise Cullen
Evangelise is a mystery, no one understands what she is. She craves blood, but she has a heartbeat faster than a humans and likes the taste of certain human foods. Frightened and alone Carlisle Cullen finds her in a darkened allyway and takes in the young teenager, promising her a home with him for as long as she wants it.
Flash forwards a few centuries and you have a twenty first century Cullen family, complete with Edward, Esme, Rosalie, Emmett, Alice and Jasper. You also have the beginning of a complicated love story which is observed through unbais eyes.
DISCLAIMER: i do not own any of the characters except for Evangelise Cullen/Eva Hale, this is so i do not have to write it in every chapter