Darkness Calls — Marjorie M. Liu

They are the obsidian shadows of my flesh -- tattoos with minds, hearts, and dreams. By day, they protect me. But when night calls to them, they leave my body, dissolving into their true form -- as demons...

Nomad born and bred, demon hunter Maxine Kiss has always relied upon herself to fight the darkness that surrounds her, the predators -- human, zombie, and otherwise -- who threaten the earth. But one man has penetrated her lonely life: Grant, the last of his kind. With the ability to manipulate energy, he can control any living creature...including demons. And now his life is in danger.

Haunted by the past, determined to change the future, Maxine soon understands that to save Grant, she has only one choice -- to lose control and release her own powers of darkness...