Whispers in the Blood by S K May

Entire countries were destroyed when the nuclear war started. The vampires never wanted to reveal their existence, but they took control of the world to ensure that it survived.

Larissa lives a sheltered life in a small town, where she's grown to accept the life laid out for her. After the sudden tragic death of her mother, her sister, Lucianna, convinces her to move to London so they can both have a fresh start. She agrees, ignoring the warnings from those close to her.

Just as things start to go her way, Larissa's life is turned upside down by her new boss, Nik Dankworth. He is the deathly attractive Lord Vampire of the region, who has set his sights on her. As Larissa discovers the hidden world of supernatural creatures, she learns that the life she knew was nothing but a lie. A lie that threatens to destroy the newfound freedom, independence, and love that she's worked so hard for.

Can Larissa survive? Or will the secrets rip her life apart?