Lilith (Lilith #1)

Lilith is an immortal who's been banished from her home, a dimensional plane suspiciously similar to mankind's idea of Hell. She's been posing as a model on Earth while secretly preying on humans... that is, until she runs into Penelope, a sweet bookstore owner with a tome that might hold the secret to returning Lilith to her dimension. If the mismatched pair doesn't end up falling in love first! "Watch out, boy, she'll chew you up."