Rose McIver continues her star turn as the likable, well-meaning, brain-eating zombie in this clever new twist on the genre. What this new series established last week is that the undead heroine Liv, as she munches on the brains of cadavers in the morgue, temporarily absorbs their memories, skills and even some of their emotions. And this week, her new dietary organ donor gives her an unexpected case of heightened libido. I guess, even when you’re a zombie, it’s true: You are what you eat…