According to stories passed down in holy writings, Cain was mankind's first murderer. Characterized with a jealous rage in which he killed his own brother, Cain was said to be cursed to wander an inhospitable Earth, unable to die. Murder doesn't just happen, though, and stories get twisted as they are handed down through time. Cain wasn't actually the first to kill another. He was, however, the first human to truly love another in a...