Twilight never thought anything would come of her adventure in the magic mirror. She and her friends had saved Equestria again, period, end of discussion. It wasn't out of the ordinary, not for her.

Then, months later, a member of the Royal Guard arrives with Sunset Shimmer, broken, humbled, and ready to become Twilight's slave... forever.

Twilight's life suddenly becomes a myriad of new complications, not the least of which is explaining all this to her friends. Everypony has a different opinion, but one thing is clear: none of this will be resolved easily. And it may just tear the Elements apart before it's finished.