AU. Sirius escaped Britain with baby Harry, saving him from a life of torture and torment. Trained far beyond his peers, he returns as a result of Dumbledore's machinations, but he's not what Magical Britain expects. {Inspired by Arcturus Peverell's "The Last of the Peverells"} Harry/OC/Daphne/Tracey/Pansy/Fleur/Tonks. Multi, Soul-Bonds, Powerful!Harry, Some Bashing