What if…  Sunset Shimmer had not just wound up at Canterlot High when she passed through the mirror, but instead had found herself in a world of supervillains and heroes, where costumed characters fought it out in the skies of New York and one young woman with no powers in this world did not have a chance to rise to her destiny.  So she decided to fix that problem, only to find her problems had just begun.

Meet Summer Lewis, a young supervillain created by The Consortium and later freed of their control by the Guardians.  Since then, she has passed in and out of the justice system, most recently released on probation only to find keeping on the right side of the law is far more difficult than it seems.

Much like where she came from originally.