All I know is that it involves Barty Crouch Sr still being alive and Sirius publicly, legally, professionally, and emotionally dragging him and the entire legal system of the Wizarding World through mass amounts of vindictive, well-deserved shit.

Lupin sees the dawn of a new era for werewolf rights and gets to teach at Hogwarts again.

They both get public apologies the Order of Merlin, First Class. Sometimes they visit Dolores Umbridge in her jail cell just to cheerily share newspaper announcements on the most recent advancements in 'half-breed' rights. Sirius apologizes to Kreacher and vice versa. Harry lives with them for a while. Lupin has a great relationship with his best friend Tonks. They have riotous annual Christmas parties with her, Andromeda, and the teenagers.

All is well.