Exorcistus

Harry Potter, age 19, enters the Veil of Death once the war has ended, unable to move on, unable to settle down. When offered a choice, he doesn't go back, and wipes the easel completely, waking up in a world where his parents lived, his brother is the Boy-Who-Lived and he wanted nothing more than to be an Exorcist. [Slash, Harry/Many AU/Time Travel Powerful!Harry, HP/Sirius incl.]