Emerald was just another human, just another pegasister. Now she's been turned into an OC pony called Twivine. Problem is, she has no idea who Twivine is.
Everypony in Equestria decides they're fed up with what they're called, so they decide to... oh look, the synopsis is pretty much in the title! Just get ready for fun, frolics... and hey, you might even learn something along the way!