Can you IMAGINE if Sirius and Harry had been truly reunited the night Harry ran away after blowing up Aunt Marge? I feel like the two of them would've been SO chaotic together. 13 year old Harry fresh from inflating his non-blood aunt and seething over the Dursleys' words about his parents, teaming up with 33 year old Sirius fresh from 12 years in Azkaban, basically frothing at the mouth to rip Peter apart and protect his godson. They would be SO fucking fun for the Wizarding World to deal with (NOT). I'm imagining a world where Harry recognizes Sirius' magical signature or some bullshit as Padfoot and isn't immediately terrified when Padfoot suddenly turns into the murderous ex-con he just saw on the news had escaped. They're both just suddenly on the run from the Ministry bc Harry is like ??? WHY DO I RECOGNIZE YOU??? And Sirius is like I'M NOT LEAVING THIS KID AGAIN LIKE I DID THAT NIGHT!!!! So they're running around Britain and Harry's getting the 411 on Peter's betrayal and cute Marauders anecdotes and Sirius is losing his mind bc OMG it's his best friend and best friend-in-law (it's a thing, OKAY!?)'s son and he's so big and sassy and angry. And then Sirius is trying to figure out where they should go, and ends up deciding to go to fuckin Moony's place even though that's the first place people who knew them back then would check bc idk luck is on their side for once idc. So Remus has the absolute pleasure of opening the door to Mr. Harry James Potter in the company of a terrifyingly familiar black dog, and Remus' alarms are firing in his head as Sirius transforms from Padfoo t back into himself and he's shouting at Remus to LET HIM EXPLAIN, while Harry is doing his best to not let Remus fire a spell at his newly discovered godfather. Eventually Remus just lets Sirius explain on his front porch steps like they're a bunch of barbarians bc he refuses to let Sirius inside or let his guard down for a single second, and then Sirius tells him the whole story and Harry pulls out the Daily Prophet, and suddenly Harry has two absolutely FUCKIN FURIOUS Marauders on his hands, and they both want to chop Peter's head off and roast it on a stick, but Harry is oddly enough the most reasonable bc he's suddenly got a godfather that he doesn't want to lose bc hey, dude's kinda really great and also doesn't hate his guts like the Dursleys do, so of course he yells at them that they can't do anything yet bc Sirius would be carted back to Azkaban and probably Remus (who is still currently this random man to him ngl but also apparently the other loyal bestie his dad had at Hogwarts, so Harry doesn't want him chucked in Azkaban either) as well. So they devise a plan that involves kidnapped the fuck outta Scabbers as soon as Ron and Harry board the train together on September 1st, and Remus already has the DADA job, so he can help w that (although he still falls asleep bc I think Moony is absolutely iconic for that). And then the three of them just chill for about a month til it's time to board the Hogwarts Express, in which everyone at the station is suitably horrified when Harry just rolls up to the train with his brand spankin new pet dog Snuffles like nothing happened and he didn't just disappear off the face of the earth for nearly a MONTH, but Harry just ignores all that shit bc boy is on a MISSION and that mission is to destroy the bastard who got his parents killed and also started the catalyst of events that led to him growing up in an abusive household for like 10 years. Which is a thing he discussed at length w Remus and Sirius because Dumbledore is a manipulative piece of shit who TOTALLY KNEW the Dursleys were awful people and still decided to place him there :))))

Basically what ends up happening is Harry asks Ron to hand Scabbers over for a minute under the pretense of idek checking his lil rat toes or some shit bc he saw one was missing ???? And then Harry kicks Remus awake to do the spell, which he does, while Ron and Hermione are becoming deeply confused and disturbed by Harry's one-track mind and clear hatred for this stupid little RAT, but they let it happen bc Hermione sees the Professor part of RJ Lupin on Remus' briefcase (which, SCORE 1 for the Marauders definitely pranking him by getting him that briefcase at some point bc they WOULD and he had never been a professor before then so ???), and Ron and Hermione don't have a problem with authority figures, that's fuckin Harry. And Remus turns Wormtail back into Peter, and we get the whole Peter begging the Trio for mercy before Sirius turns back into himself from Padfoot, at which time Ron and Hermione start yelling about the escaped very dangerous convict in their TRAIN CAR, while Harry tries to convince them that Sirius isn't a danger to anyone in the tiny space but the fucking RAT, at which time Ron is like WELL HE'S NOT ACTUALLY A RAT ANYMORE NOW IS HE HARRY???!!! And Harry has to go with the short version of HE BETRAYED MY PARENTS RONALD!!!! while Peter is cornered by Sirius and Remus. And no, nobody has heard the yelling yet bc obviously Remus cast the Muffliato Charm or something, of course he did, I wouldn't forget that people have EARS. And then all of the sudden, the train car starts getting all cold, so Remus starts yelling at Sirius to change back to Padfoot bc the dementors won't sense a human that could be Kissed if he's not in human form, and Sirius does, but Peter also tries and Ron realizes what's happening and knocks him out (why Ron? Idk, why NOT him honestly, it's what he deserves after letting that creepy motherfucker live with him for the past few years bc YIKES I would be so freaked out) before Peter can turn back into a rat. The dementors come into the train car and Harry has his fainting spell which makes Sirius and Remus suitably LOSE THEIR MINDS bc WHAT THE FUCK JUST HAPPENED TO THE KID?!!??!! and Remus uses the Patronus Charm to repel them even though it means Peter won't be Kissed and Remus really wants revenge.

So Harry wakes up and is immediately accosted by his best friends, Sirius back in human form, and Remus trying to force chocolate into him. Ron and Hermione have been suitably informed of the situation, so they've closed the curtains, and nobody even knows what's happened besides those in the train car with them. Sirius doesn't have his wand, but he resolves to sit as Padfoot, staring at an unconscious Peter for the rest of the journey to Hogwarts, and the other four join him because no way in HELL are they letting that MF escape after Harry and Remus have managed to explain everything (and even before bc Ron and Hermione are the best and all they needed to hear was that Harry's parents died bc of Peter to determine that they would fucking the rat UP if he tried anything at all). So of course this weird fuckin quintet shows up to Hogsmeade's station with the real traitor and have to wait for everyone else to exit the train before traipsing up to the castle with the still unconscious Peter (Ron may not have cared all that much about being careful with head injuries from knocking bastards out bc of the whole ya know TRAITOR thing). Remus manages to send off a Patronus message to McGonagall (her bc of the aforementioned Dumbledore is a shithead thing) and they all head to Remus' new office with Peter in tow. Minerva shows up to Sirius as Padfoot, but an unconscious man who is CLEARLY Peter Pettigrew, and she's immediately like WHAT THE HELL??? and calls in some Aurors to deal with the trash. The Aurors are all suitably horrified but clear out soon bc they're not important to this story (sorry, kisses Aurors😘), and Minerva starts raging about Sirius being innocent and how DARE Peter, to which the Trio are extremely horrified bc they've never seen her lose her shit QUITE this much and it is highkey terrifying, but Remus is enjoying the show bc at least SOMEONE AGREES and Padfoot is wagging his tail and panting happily before Sirius realizes that Minerva can KNOW and he transforms back into himself, giving the poor professor half a heart attack. And because I think it would be hilarious for me personally, Snape walks in at the end of this lil story to see where tf Remus is bc he and Minerva are BOTH missing from the Welcome Feast, to Minerva McGonagall hugging the life out of a beaming Sirius Black while Remus looks at the two of them with a huge amount of relief bc THANK GOD she accepted his innocence, that could've been so bad for them lmao, they couldn't even Disapparate away at Hogwarts if she decided he wasn't innocent after all. And then Snape sees the Trio right beside Remus, also watching the hug and grinning like fools, especially Harry bc this meant Sirius was going to be FREE and also Harry would never have to deal with seeing the Dursleys or dealing with the fact that he literally blew up Dudley's aunt ever :)))