Immortality—or a functional equivalent—is one of those situations that presents an interesting challenge to writers. It has no real life equivalent, so writers have nothing to reference to give it verisimilitude. Like all unorthodox situations, the freedom available to writers is offset by the need to ground it in reality and consistency. How would one react to situations, how would they act, if they had lived for centuries or millenia? How would it affect their outlook? Or their emotions?