Spend even a few moments with Nikki Williams and you know that's exactly what you're dealing with: an unapologetic, balls-out truth-teller, an old soul at 24 with a killer set of pipes and the attitude to match. A natural born storyteller and a gifted singer-songwriter, Williams is the personification of Newtonian law: a body in motion will stay in motion. "I was born to do this," she says. "There is no Plan B. This is it. You don't ignore an instinct."...