Chapter Text
A lifetime ago, Lily Potter and Alice Longbottom had asked for Sirius’s help translating some ancient runes.
Moony had been the more obvious choice, with his outstanding runes NEWT, but Dumbledore had him on assignment with the werewolf packs in Scotland and he was unavailable. While Sirius wasn’t as good, he was the only other member of their little friend group aside from the girls and Frank that had taken it.
They’d poured over tomes that had to have been pilfered from the Black family libraries back when the Potter and Longbottom association with them was more familial, some surprisingly dark texts that had been holed up in shady corners of family vaults, and horrifying spells from Alice’s job as a cursebreaker.
What they had been looking at was all remarkably illegal blood rituals, meant to extend someone’s life and defend against harm. They were finicky, and usually required the sacrifice of a virgin or two. Frank and Lily had thought they could tie the spell to a bloodline instead, to have it pull on love and connection to bolster the protections.
Sirius had worn dark robes and chanted at James and Alice’s side as the three of them watched Frank and Lily draw complicated sigils, and ritual circles, and covered themselves and their babies in bloody runes until there was more red than tan on their skin. The only thing left was the sacrifice they hoped would never have to come.
All of which Sirius regretted when his fifteenth locator spell fizzled out with an explosive BANG.
He cursed, and Kreacher cackled from the back corner of the library, where the elf was definitely stealing cursed books from the shelves before Sirius could get to them.
“Very helpful, thank you Kreacher,” Sirius grouched, rubbing the back of his head where it had hit the floor in his dive to safety.
“Kreacher is not trying to help,” the elf replied happily, “Kreacher is enjoying watching the mutt fail.”
Sirius kicked the desk in frustration, its contents sliding around in the locked drawer he still couldn’t magic open. A chill was spreading down his arms and legs the longer he tried and failed to find his boy.
He was really running out of ideas. There were only so many spells he had access to, and he was reluctant to resort to the family grimoires. Who knows what kinds of curses were on those things?
“The heir is well hidden.”
“Yeah, his mum was a damn powerful witch,” Sirius said wistfully, “I don’t think there’s a force on earth that could find him, after all the rituals she did.”
Kreacher scoffed.
“Then look for the filthy squib sister, stupid mutt.”
With a crack, he disappeared with a pile of books, some of which looked like they were bound in skin.
Sirius brightened. Of course! Petunia would never have agreed to sit down for any sort of spell, especially not one as complicated as Frank and Lily’s experimental blood wards.
He quickly duplicated the rune circle that had blown up in his face just minutes before, writing “Petunia Evans” to the center instead of “Harry Potter”.
“Locum eora revela”
He waved his wand in a complicated squiggling pattern, preparing to leap away if it blew up in his face.
Instead, the parchment crinkled at the edges, browning and curling until it lit up in a white-violet flame. Sirius watched in fascination as it burnt to a crisp, leaving only a soft, glowing orb that floated through him and into his chest. Suddenly, he knew exactly where to go.
In a blink, he apparated, leaving Kreacher to plunder the library in peace. The elf cackled as he dashed through the door, shoving trinkets and books carefully in a hairy bag made from an acromantula’s abdomen.
——————————
Sirius reappeared in the middle of a muggle greengrocer, hastily casting a disillusionment charm on himself and praying he hadn’t been seen.
About ten feet to his left stood a little family, checking out the price on cauliflower.
A fat, pasty little blond boy was throwing a fit from the carriage, shrieking about how much he hated vegetables, while a horse-faced woman– Petunia, upon whom time had bestowed no favors– frantically assured him that he wouldn’t have to eat any, not to worry Duddykins.
At her knees stood a waifish dark-haired boy with tan skin who sported a black eye and about seven bags of produce.
Harry! It was Harry!
Tears welled up in Sirius’s eyes. He hugged himself tightly, reigning in the overwhelming urge to pull his godson into his arms and just hold him again.
Then the blond boy kicked his head from his seat in the carriage, making him drop one of his bags.
Cold shot up Sirius’s throat and down his arms as Petunia smacked Harry on the back of his head, lecturing him about being more careful while her son laughed and laughed.
This was his fault. How could he have been so stupid, leaving Harry behind all those years ago?
It felt like he was swallowing icy seawater, like he had on his escape from Azkaban, spreading icy tendrils from his stomach and making him gag on the brine. He choked the feeling down, forcing his heavy limbs to trudge on, following behind Harry and his aunt. Eventually, Petunia finished paying for her produce, and Sirius had finally gotten a handle on the cold.
She had poor Harry load the bags into her sensible sedan, scoffing as he struggled to lift them into the trunk. While she bundled her precious son into the car, Harry dropped another bag as he raised it over his head, letting an apple fall out onto the ground.
Petunia snatched Harry’s ear, wrenching it between her fingers while he made an aborted cry of pain.
“I’m sorry Aunt Petunia, I didn’t mean to! It was just too high and–”
“I don’t want to hear any of your complaining! Since you can’t be trusted to handle our things with care, you need to be taught a lesson.”
She slammed the car door shut, pushing Harry to the side.
“You will make your own way home. I’ll expect you home before dark, or the door will be locked. Am I understood?”
For a moment, Harry looked like he was going to fight back, his chest puffing out in righteous indignation, but he finally slumped, curling in on himself.
“Yes, Aunt Petunia.”
He stepped out of the way of the car, watching sadly as Petunia and her laughing brat peeled out of the parking lot, leaving a skid of rubber on the asphalt.
The little boy stood there for a minute, looking very small and very lost, before putting his head down and starting to walk.
Sirius followed behind him for as long as he could handle, watching him slowly start tripping over cracks in the sidewalk as the long walk weighed on him, before he finally gave up, changing into Padfoot.
His dog brain kicked in and he yipped excitedly, running up to Harry, who turned and shrieked with fear.
Instantly, Padfoot sat in place, making himself as small as possible while his tail wagged excitedly.
Harry stared at him, half turned to run, before steeling himself and stepping forward.
“I don’t really like dogs very much,” he said, tentatively petting Padfoot on the head, “Aunt Marge’s bulldog always tries to bite me. But you seem very nice.”
Padfoot huffed in agreement, pressing into his side.
“I wish it was a longer walk to get home. Uncle Vernon doesn’t like dogs, and he definitely doesn’t like it when anything’s kind to me. He’ll make you leave.”
Sirius whined at the thought of someone denying his sweet boy kindness.
Suddenly, he had a thought. A great thought, best thought of the week.
Lowering into a crouch, he shoved his big head between Harry’s legs and lifted the boy onto his shoulders while he squealed. Harry flailed for a moment before hooking one leg into the strap of Sirius’s bag and grabbing frantically at his scruff.
Padfoot started out into a trot while Harry giggled incredulously.
“I didn’t know dogs could let people ride them! Would you mind going right up ahead?”
Dutifully, he turned right down the next street. Harry was right, of course, a normal dog would never be able to let him ride on them, but Grims are much stronger than a normal animal.
“Woah! Can you understand me?”
Barking in affirmation, Padfoot risked breaking out into a light run, following along with Harry’s directions until they came to a stop outside of a little white cookie-cutter house among rows of other cookie-cutter houses in varying shades of eggshell to beige.
“This is where I live,” Harry explained as he slid off, “Thank you for the ride!”
Padfoot licked his face, and he laughed.
“I really hope I see you again.”
In response, Padfoot walked to the front of the house and curled up under a big hydrangea bush.
Through a break in the leaves, he could see Harry smiling as he went through the door.