I made an archiveofourown account recently and will be posting this story there as well, so if you prefer AO3, you can go on there and read

Last edited: October 5, 2021 (one paragraph)

Harry approached Ron Weasley as he was leaving for the train. "Hey, Ron. Sorry about your rat."

Ron waved it off. "It's fine. Actually, I'm glad you found out. Keeping a killer in my own dorm..." He brightened up. "Black sent me an owl," he told Harry. "To replace Scabbers- er, Pettigr- him."

Harry grinned. "That's great." He glanced over at Hermione. "Have you apologized?"

Ron followed his gaze. "Oh, no. I haven't. Not yet." He walked over to Hermione and said something to her. She smiled and nodded, clearly accepting his words and the two went to find a compartment.

Watching them, Harry felt a pang of envy. He could tell that they liked each other, even if they themselves were not aware of this fact, and couldn't help but yearn for that kind of relationship. A flash of red caught his eye and Harry looked up to see Fred and George coming his way.

"Looks like Sirius Black wasn't trying to kill you after all, hm?" George said.

Harry groaned. "Not you, too." He had been dodging students all morning, asking about Sirius Black and Remus Lupin. As the latter had predicted, owls had come in demanding that Remus get sacked, unaware of the fact that he had already resigned.

"Don't worry, Harrykins," Fred said. "We won't ask about that."

"But," George added, "we would like to ask you something."

"And that is...?"

"Is Sirius one of the Marauders?" they said in unison.

"Perhaps."

"Come on, Har, don't keep us in the dark." Fred pouted hopefully.

And Harry could not resist it for some reason. "Okay, yes. He is."

"Can we meet him?" they asked.

"Yeah, he'll be waiting at the platform," Harry said.

They boarded the train.

To Harry's utter delight, as he was getting off the train, Remus was with Sirius. "You're here! Both of you!"

Remus laughed. "Sirius convinced me to move in."

Fred and George were staring at Sirius, not even trying to hide their awe. "So you are-" George began.

"-another legendary Marauder?" Fred finished.

Sirius nodded and ended up staggering as the twins hugged him and fake cried.

"We are not worthy!" they said.

"Um, Harry," Sirius said as he patted them on the backs, "care to introduce these two gentlemen?"

"I'm George," Fred said.

"And I'm Fred," George added.

"They're messing with you," Harry said. "It's the other way around."

"Wait, what?" Sirius looked confused.

"I'm George, this is Fred," George said.

"Also known as Gred and Forge," Fred said, successfully confusing Sirius even further.

"Anyway!" Harry said, slightly louder than necessary. "Fred, George, as you know, this is Sirius Black also known as Padfoot and you've already met Moony."

"Oh, did Harry tell you?" A wicked gleam shone in Sirius' eyes. "Prongs was James Potter."

Harry barely had time to shoot a scorching glare at his godfather before the twins turned to him. "Why didn't you tell us?!" they exclaimed.

"I don't know!" Harry said. "I forgot?"

"You're lucky you're cute," Fred said, arms wrapped around him and chin resting on Harry's shoulder. "Otherwise, I might not forgive you for 'forgetting' to tell us."

"Boys!" Mrs. Weasley called. "Stop bothering Harry and come here!"

"Bothering Harry?" George grumbled as he reluctantly stepped away.

"As if!" Fred scoffed, not moving from his position. "He loves us, right, Harry?" He turned his head, face mere inches from Harry's.

Sirius watched with interest as Harry became a flustered mess and stuttered out a chain of incoherent words. Are they going to kiss...? he wondered. He waited with bated breath.

To Sirius' disappointment, Fred finally detached himself and went to join the rest of his family.

"Come on, you two," Sirius said to Harry and Remus. "Let's go."

"So how did my aunt and uncle react to you?" Harry asked, trying not to think about just how tempting it had been to lean in just a little bit closer to Fred and thinking of nothing else.

A grim expression crossed Sirius' face. "Let's just say that your relatives were very quick to hand you over."

Harry wouldn't have expected anything else.

Number Twelve, Grimmauld Place was situated between Muggle houses. Harry followed Sirius and Remus inside, staring around at the dusty place.

"Not my favorite place, but I grew up here," Sirius said.

"Well, once it's cleaned up, I'm sure it'll look okay," Harry said optimistically.

"Kreacher!"

There was a pop, and an elderly house-elf appeared. He glared up at the occupants in the room. "Master has returned with werewolf. What would my poor mistress say?" He turned to Harry. "There's new boy, Kreacher doesn't know his name. What is he doing here? Kreacher doesn't know..."

"This is Harry Potter," Sirius said. "He'll be living here now."

"Is it true? Is it Harry Potter? Kreacher can see the scar, it must be true, that's the boy who stopped the Dark Lord, Kreacher wonders how he did it-"

"That's enough, Kreacher," Sirius snapped impatiently. "Now what have you been doing while I was... out?"

"Cleaning," Kreacher said evasively.

"Yet this place looks blacker than ever."

"Master always like his little joke," Kreacher muttered. "Master was a nasty ungrateful swine who broke his mother's heart-"

"My mother didn't have a heart, Kreacher," snapped Sirius. "She kept herself alive out of pure spite."

"Sirius," Remus said in a warning tone.

"Right, right. Kreacher, you are going to help get this place clean. And I mean actually clean, not whatever the hell this shit is."

"Sirius!" Remus hissed as Kreacher popped away, gesturing to Harry. "Language!"

"Oh, please. Remember when you babysat Harry?"

"That was one time!"

"What happened?" Harry asked.

"Moony here lost the pacifier and got really irritated."

"I may have broken the record for most curse words in a minute," Remus admitted.

Harry laughed. "I wish I remembered that."

"No, that's probably not a good idea. Anyway, we better show you your room."

"My room? I get my own room?" Harry blurted out.

Sirius winced a little. Remus had filled him in on what little he had gleaned of Harry's life at the Dursleys. A cupboard. They put his godson in a damn cupboard! "Of course you do, pup."

"And... what about meals? I can cook-"

"No, Harry." Sirius leaned in close so he could look directly into Harry's eyes. "Forget about the Dursleys. They did a sh- bad job with you," he quickly amended at the warning cough from Remus.

"You were going to say shit, weren't you?"

"Harry!" Remus groaned. "Great job, Padfoot. You've already started courrupting him."

"Hey!"

For the first week, Harry had to be careful of moving around Grimmauld Place. The lack of care meant that the entire building was filthy and creatures could have gotten in. He also met Sirius' mother's portrait and did his best to avoid her at all costs. She was... loud, to put it lightly.

He was walking past the stuffed elf-heads- he shuddered every time he saw them- only to stop when he heard a noise. Harry looked into the drawing room and gasped.

Remus Lupin's dead body was lying in a patch of moonlight. But Harry had just seen Remus...

Sirius raised his wand. "Riddikulus!" he chanted in a slightly shaky voice.

Remus' body turned into Harry's. "Riddikulus!" Sirius shouted again.

Dead Lily. Dead James.

Sirius' eyes squeezed shut upon seeing his best friend. "No, no, no," he moaned.

Remus raced inside, took one look, and pulled out his wand and said, "Riddikulus!"

It turned into an orb, then vanished in a puff of smoke with another wave of his wand.

"Padfoot," Remus said gently. "Look at me."

Sirius looked up. "I'm such an idiot," he said. "I just took off that night. I gave up my godson to go after Wormtail." He spat out the name like it was poison.

Harry watched as Sirius broke down in front of him, feeling helpless as Remus brought him into his arms.

Remember the Boggart scene from Order of the Phoenix? I just moved it here