Sunset Shimmer and her Sidekick: long live the princess

Instead of stealing the Element of Magic, Sunset Shimmer finds yet another human world and a human with strange powers. She pulls both into Equestria, where he turns into a Pegasus with new powers. Now both set out to a journey in order for Sunset to become an alicorn princess. Will it work? [Pairings undecided; taking suggestions; Cover art by KHTwilightSparkle from deviantart]