Grave Peril (The Dresden Files, #3)

by Jim Butcher

The male smiled and put a hand on her shoulder, a gesture that was half affection, half physical restraint. “My sister hasn’t eaten tonight,” he explained. “She’s on a diet.” “Vampires on a diet?” Susan murmured beneath her breath. “Yeah,” I said back, sotto voce. “Make hers a Blood Lite.” Susan made a choking sound.