Death Valley by Karina Halle

Three years ago Aubrey Wells’ sister disappeared in the Sierra Nevada Mountains. Since then, Aubrey’s life has crumbled around her. Desperate for answers, she hires rancher and wilderness guide Jensen McGraw to help discover what happened to her sister.
Jensen doesn’t frighten easily. Hell, the finances of his family’s ranch are mixed up with one of the world’s most dangerous crime bosses, but he knows exactly what kind of unnatural creatures wait up in those mountains. He tries to convince Aubrey to give up, but he needs the money she offers if he wants to retake control of his ranch.
Business isn’t the only thing brewing between Aubrey and Jensen—secrets, lies, and an intense attraction threaten to derail their journey up the mountain. When a fierce snowstorm hits, and members of the crew start disappearing, Aubrey and Jensen will have to use all their wits to survive.
Because what dies in this wilderness doesn’t stay dead… it devours.