The Marauder Chronicles

In the aftermath of Grindelwald's defeat, Dumbledore is reminded that not even a brilliant mind can cure him of a human heart, with all its temptations. While Dumbledore is in the midst of his own rediscovery and tracking Tom Riddle, Sirius arrives at Hogwarts to quite accidentally create an enemy out of Severus Snape by catching the notice of the wrong girl. (SnapexLilyxSirius)