Before he knew it, Sirius was back in front of the wall between platform nine and ten with his trunk and owl.
Arcturus approached, and Sirius' mother began to explain the barrier to him.
Sirius pushed his trolley up to the wall and casually leaned up against it. He disappeared through it, and found himself on the platform next to the Hogwarts express. He moved out of the way quickly, and just in time, as Arcturus came speeding through the wall not a second later. He looked stunned, and skidded to a stop. Sirius laughed.
"It's cool, huh?" He said. Arcturus glanced around at all of the other students crowding the platform. Arcturus was wearing a white shirt and a pair of jeans, as was Sirius (only his shirt was black), against his mother's request to 'stop acting like he's some kind of filthy half blood' and that he should wear robes instead. Soon after, everybody was on the platform, and Sirius waved his parents goodbye and jumped onto the train. Arcturus was hot on his heels.
"So, how long is this trip?" He seemed sort of nervous,
"Oh just a few hours." Sirius shrugged, searching for a compartment.
The train whistled and the last stragglers leaped onto the vehicle so as not to miss it. Finally, Sirius opened the door on an empty compartment and led the way inside, storing his trunk and tawny owl, 'Owlbert', in the luggage rack above his head.
Arcturus followed suit, putting his own trunk and his rather unimpressed looking fluffy white cat in its black cat carrier in the luggage rack as well.
"A cat, huh?" Sirius never really did like cats much.
"Yeah, well... cats are my favourite animal, actually." Arcturus shrugged one shoulder, "her name is Wisp" He added, and then sat down. Sirius couldn't help but notice that he was sitting up very straight, which wasn't surprising, what with him being a Black. Sirius also noticed that he seemed kind of tense.
"Hey, relax. I think you'll really fit in here." Sirius assured him. Arcturus' blue eyes flicked up to meet his own grey pair.
"You reckon?" The curly haired boy looked hopeful. Sirius allowed his signature smirk to pull at his features and leaned back in his seat in a way that only he could ever do. Nobody pulled off a relaxed slouch like Sirius. Arcturus raised an eyebrow, but before he could open his mouth to question Sirius' position, the compartment door banged open and James bounded in.
"SIRIUS!" he shouted jovially. "We're going back to Hogwarts!!" He grinned, punching the air. Then he noticed the slightly ruffled looking Arcturus, who was staring at him as though he was completely mad. Sirius laughed loudly.
"This is my cousin, Arcturus. He only just moved over to Hogwarts." James looked quite embarrassed, and a little bit sceptical of the new arrival.
"I'm James Potter." He introduced himself, "and... uh- before you ask about the last name, yes my family does associate with muggleborns." James then sat down awkwardly in the furthest seat away from Arcturus'. Sirius smiled.
"Arcturus isn't like the other Blacks, James." James looked like he might say something, but Peter and Remus decided to come in right at that moment.
"Hey Siri- oh." Peter hesitated at the door, shying away from the newcomer seated casually in their compartment. Remus stepped through the door.
"I'm Remus Lupin. Are you new around here?" Remus said in his usual, reserved sort of tone.
"This is my cousin, Arcturus." Sirius nodded towards him. Peter was still in the door, looking even more nervous at this news, Remus looked as sceptical as James had looked, and James finally piped up.
"About that... being a Black-" he began to say, but Arcturus cut him off.
"I don't agree with their views." He stated calmly.
Remus, James and Peter all stared. "They're wrong. Call me a blood traitor, but I think the whole pureblood attitude is just fucking dumb."
Peter flinched at the curse word, but Remus seemed to disregard it completely.
"I think you're right, Arcturus." He said quietly. Remus then loaded his trunk into the luggage rack, and took the seat right beside Arcturus. Peter followed suit and sat beside Sirius.
"So, do you know what house you'll be in yet?" Remus tried to get a conversation going.
"Uh- not really. I like the idea of being in Griffindor, but I'm not really brave..." he trailed off.
"I reckon you've got some nerve, saying that you disagree with your family... i mean, if your parents are anything like Sirius'..." James trailed off, smiling.
"Yeah... I guess so, I dunno." Arcturus shrugged again. Just then, the compartment door slid open and there stood none other than the fiery-haired and very beautiful Lily Evans. Beside her was Alice Lightwood, her attractive, light brown haired best friend.
"How can I help you, Evans?" James sat up a little bit straighter, and shot her his cockiest grin.
"We heard there was a new guy in this compartment. We came to say hello." Alice said simply, while Evans frowned at James.
"Hello." Arcturus waved his hand. The two girls' eyes moved to his face, taking in his features.
"I'm Lily and this is Alice." Lily smiled warmly.
"I'm Arcturus." He allowed a little smile to pull at his lips. "Where did you two pretty ladies come from?" He raised his chin slightly, never taking his shockingly blue eyes off of the girls. The two young Griffindors giggled and blushed.
"If you need any help, just ask us!" Said Lily.
"We'll see you later, 'kay?" Alice smiled, and led Lily away by the hand, back down the train. There was a moment of silence, and then the door banged shut.
"What was that?!" James was fuming and glaring at Arcturus. The curly haired newcomer shrugged.
"Why are you so angry, dude?!" He questioned, incredulous. "She was frowning at you. I thought you must hate each other. Besides, it was just a bit of flirting." He explained. James glared daggers at him, and leaned forward in his seat to meet Arcturus' eyes.
"Lily. Evans. Is. Off. Bounds." He told him firmly. Arcturus looked slightly taken aback and upset.
"Okay, James. He didn't know. Just calm down." Remus spoke up, putting a hand on James' shoulder. James slumped down where he sat, staring grumpily across at the empty seat opposite.
"James has been trying to get Lily Evans to notice him since first year." Sirius told his cousin. "He's a bit overprotective."
"I'm sorry, James. I had no idea, man!" He apologised, "I won't go there ever again with Evans." Arcturus sounded very genuine.
"Thankyou." James' tone sounded happier.
"Don't mention it. There's plenty of other girls at Hogwarts." Arcturus waved his thanks away.
"Why are you flirting like that anyway?" Peter asked nervously, then pressed his hand over his mouth as if the question had slipped out without him meaning it to.
"Why?..." he glanced around at them."Don't you guys?" Arcturus seemed slightly suprised.
"Jamie does with Lily, but you know... the rest of us just don't flirt with any girls." Sirius said.
"Well if the rest of the chicks at Hogwarts look like that, I don't know how you resist it." He responded.
"I- I don't want a girl..." Peter stuttered slightly.
"Yeah you do. I mean of course you do. You're fifteen years old for fucks sake!" Arcturus shook his head in disbelief.
"Well, I dunno. I wouldn't mind an hour in a broom closet with one, but I'm not one to date." Sirius said.
"An hour?" James laughed, "three minutes maybe!" He teased his friend. Sirius blinked at him for a moment, while everyone else laughed.
"Hey, at least Sirius here has been with a girl!" Arcturus turned it on James, and he and the other boys laughed again. When everything calmed down again, James said,
"And what- you have?"
"Oh, many a time, Jamie boy." Arcturus chuckled. James narrowed his eyes.
"I bet you can't even remember those girls' names." He stated.
"Uhh- well no. But that's not important." Arcturus replied,
"Isn't that a little shallow?" The messy haired quidditch player challenged,
"Only as shallow as your mother." Arcturus raised an eyebrow. James' eyes widened, not knowing what to say, but then Sirius piped up, amused.
"Yuck, Arcturus! I didn't know you were into that!" This comment roused laughter from everyone, including Arcturus himself. The door opened again, revealing Alice Lightwood... again. Only this time she had Nuna Baer with her instead of Lily.
"Oh- sorry. We can come back later if you l-like-" Nuna stammered, taking in the amused group of friends. Nuna was a small, petite (usually) blonde Griffindor metamorphagus in their year. She came across as nervous most of the time, and she could often be seen standing to the back of her friends, peeking out through her big blue eyes from behind her long hair, which always fell in front of her face. Remus smiled his reserved smile and shook his head.
"No, Nuna. You can come right in." He told her, and then rose from his seat. "Have my seat." He offered. Nuna sat down cautiously. Sirius and James exchanged knowing glances.
"Nuna wanted to meet Arcturus." Alice smiled,
"Hey, Nuna." Arcturus smiled in a friendly way. Nuna blinked three times, fast and her hair turned a very light blue.
"Hullo." She said quietly. Remus grinned giddily from his place leaning against the doorframe, and his friends all smiled knowingly at one another. Nuna glanced up at Remus, who immediately looked away from her and tried to stop smiling.
"So- er- how were your holidays, Remus?" She asked him. Remus jumped a little at being adressed.
"Oh- good!" He smiled, "and you?"
"It was really good, but I'm glad to be back at Hogwarts." She admitted, and then blushed. Her now blonde hair drifted over her left eye. Nuna didn't bother to move it out of the way.
"We'll be arriving soon, so we should probably go change." Alice suggested. Nuna looked up.
"Oh- yes of course." She agreed. Remus offered her his hand. Nuna hesitated for a moment.
"Oh! Th-thankyou." She linked hands with him, and he helped her up. They let go almost immediately, and Nuna blushed as she briskly made her way out. Sirius was almost positive her hair had turned bright pink before she could disappear. Alice smiled towards Arcturus, and he winked, and then she waved them all goodbye, closing the door behind her.
The five of them changed quickly into their Hogwarts robes, and soon enough the train began to slow down for Hogsmead station. Arcturus reached for his baggage, but Sirius put a hand on his shoulder and shook his head.
"The house elves will take care of it. C'mon." He told him, and led the way out of the compartment and into the crowded corridor beyond.

Author's note
Hey there, cheers for reading my fanfic!
More soon
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