Gryffindor
It wasn't uncommon for the children of the Black and Travers houses to study together. Music was a newer on take, but there were others that they couldn't remember ever not doing. One of those things were their language classes. All three were fully fluent in French, Spanish, Arabic, and Russian on top of English so it was not uncommon for the children to communicate in such a way when they didn't want to be understood. Walburga, impressive as she was with her own five languages had failed Russian again and again in her own youth and so substituted it with Latin, which was honestly more useful. She was insistent that they learn it, but only Morgana and Regulus had made any serious progress in it. So, in times like these, when they didn't want to be understood, they spoke Russian to one another.
"I sure am gonna miss my malenʹkiye ublyudki," Sirius said. Swearing was frowned upon in the Black household and even more so in the Travers house so calling them "little shits" or "little bastards" even in Russian was a risk.
"Promise you'll write!" Regulus exclaimed.
"Every day!" Morgana added. He may not be her bestest friend in the whole wide world, but Sirius was like an older brother to her too.
"Hey, not every day! Do you want me to fail my classes?"
"Fine every two days."
"Once a week?"
"Deal!"
Walburga and Orion, Sirius and Regulus's father, chuckled before each putting a hand on Sirius's shoulders and wishing him well. They told him to make him proud and Sirius grinned and straightened his tie. With that, Sirius climbed aboard the Hogwarts Express and was out of view. The children, 10 now, ran up to the side of the train to find the window that he would poke his head out of to wave goodbye. Sure enough, they found him and took off running with the train till the end of the platform, waving frantically with the other younger siblings.
Once the train had fully left the platform, Sirius sunk down into his seat, both relieved and extremely lonely. It had never occurred to him that he'd be living a year without his little brother and Morgana, or at least, it hadn't fully sunk in until now. But he was soon distracted from his feelings when a red-headed girl walked in. She had been crying he could see, eyes red and slightly puffy. Sirius could tell this would be her first true time away from home.
"Mind if I sit here?" She asked, her voice shook a bit but he could tell she was trying to hide it. He simply smiled and nodded which seemed to brighten her up even if just a bit.
They didn't speak even when another boy came in and sat without a word. He had black messy hair and glasses. But they didn't make him look nerdy like you'd expect, but rather complemented his facial structure. He was apparently more restless than Sirius or the red-haired girl but still didn't seem to be interested in either of them. They were all lost in their own thoughts.
Another boy slid open the compartment door and sat down opposite the red-haired girl. She glanced at him and then looked back out of the window.
"I don't want to talk to you," she said in a constricted voice.
"Why not?" he asked somewhat imperdantley. He was greasy, not just his hair but his clothes, his skin, it all looked oily. His hooked nose paired with the previously stated gave him the impression of a vulture.
"Tuney h-hates me. Because we saw that letter from Dumbledore." That was a person Sirius recognized. His father and mother had always criticized Dumbledore, said he was a stupid muggle lover, but he could tell that part of them feared him.
"So what?" the boy asked dismissively. Sirius was getting the impression that he wasn't a very good friend. He knew Morgana would never be so dismissive.
She threw him a look of deep dislike. "So she's my sister!"
"She's only a--" but he caught himself quickly; the girl, too busy trying to wipe her eyes without being noticed, did not hear him. Sirius filled the word in his head: mudblood. It wasn’t something taught directly to him but it was what he grew up with. His family hated mudbloods.
"But we're going!" he said, unable to suppress the exhilaration in his voice. "This is it! We're off to Hogwarts."
She nodded, mopping her eyes, and in spite of herself, she half smiled.
"You'd better be in Slytherin," said Snape, encouraged that she had brightened a little.
"Slytherin?" the other boy sharing the compartment looked around at the word. "Who wants to be in Slytherin? I think I'd leave, wouldn't you?"
He turned to Sirius with a smile, looking for confirmation. Sirius did not smile. "My whole family has been in Slytherin."
"Blimey," said the boy, "and I thought you seemed all right!"
There was something so utterly captivating about this boy that Sirius grinned. "Maybe I'll break the tradition. Where are you heading, if you've got the choice?"
What was he saying!? He wanted to be in Slytherin. He needed to be in Slytherin. The boy lifted an invisible sword. "'Gryffindor, where dwell the brave at heart!' Like my dad."
The greasy one made a small, disparaging noise and the glasses boy turned on him. "Got a problem with that?"
"No," he said, though his slight sneer said otherwise. "If you'd rather be brawny than brainy--"
"Where're you hoping to go, seeing as you're neither?" interjected Sirius. He didn't like the greasy boy and the words were out of his mouth before he could stop them.
The glasses boy roared with laughter. the redhead sat up, rather flushed, and looked from glasses to Sirius in dislike. "Come on, Severus, let's find another compartment."
"Oooooo..." Sirius imitated her lofty voice the boy and tried to trip, as he now knew he was called, Severus, as he passed.
"See ya, Snivellus!" the boy called, as the compartment door slammed... he then turned back to Sirius. "I'm James by the way, James Potter."
Sirius smiled, he had made his first friend.
The boat ride to the castle had been rough as it was mildly stormy, but the grounds keeper, Hagrid, and a scarred boy called Remus who had read Hogwarts a History said that it was perfectly safe. The sweets stuffed in their pockets were lost though.
Once on the grounds, they were greeted by a stern-looking lady who introduced herself as Professor McGonagall. She looked to be the sort of woman you wouldn't want to cross, but being used to his mother, Sirius found a sort of comfort in her. She briefed them on the sorting process, but there Sirius zoned out. He would be in Slytherin just like every single Black before him.
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Strange how silence is almost more defaning than cheering. That's how Sirius felt when the hat called out his house. The entire hall was silent as it was removed from his head. No Black in a thousand years, or however old this bloody school was, had been in anything other than Slytherin. But there the word echoed out to the entire crowd. To those that knew him, and those that didn't.
“Gryffindor!”