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For the past three weeks, since everyone had returned from winter break, Regulus had been avoiding Sirius. Not subtly, either. He slipped out of rooms the second Sirius entered, turned sharply down corridors like he’d just remembered something urgent, kept his head tucked low at meals. Always with someone else, always with Crouch or Rosier at his side. It was calculated. Controlled. Distant in the exact way that would hurt Sirius most.
James told him to let Regulus go. Said the boy was a lost cause. Said he made his choices, and Sirius had made his.
But Sirius couldn’t.
Ever since he’d run away from Grimmauld Place, Sirius had been watching over Regulus from afar. Not obviously. Not closely. But always.
Regulus, who came back from every break a little paler, a little skinnier, a little more frozen.
Regulus, who returned from this break limping.
Regulus, who wouldn’t meet his gaze once.
And Sirius couldn’t take it anymore.
He knew better than to approach his brother publicly. He did. That was a rule they both had learned early. Slytherin didn’t associate with Gryffindor, not even if they shared a last name. Especially not if they shared a last name.
But Regulus had been glued to the other Slytherins since term began, and Sirius had no other choice.
So he walked straight to the Slytherin table at breakfast.
He stood over his little brother, casting a shadow that stretched between the porridge and pumpkin juice.
The first-year on Regulus’s right glanced up at Sirius, wary and wide-eyed, but Regulus didn’t move.
“Reggie,” Sirius hissed under his breath. “Our room. Tomorrow night.”
Sirius didn’t expect a response. He never did. But the one he got made his stomach drop through the floor.
Regulus’s spoon clinked three times as he set it in his bowl.
Three clear, metallic taps.
He hadn’t made that mistake since he was a toddler, still learning table manners under their mother’s sharp eye. Clinking your spoon meant shaky hands. Clinking your spoon meant punishment.
And Regulus never made mistakes. Not unless something was very wrong.
Sirius let out a slow breath as he turned away. He didn’t look back. He didn’t want to see who was watching.
Regulus wasn’t hurt. Not in a way Sirius could heal for him.
Sirius waited in the abandoned classroom they had chosen together in Regulus’s first year. It was tucked down an unused hallway in the far wing of the castle, past a door that always stuck and under a shattered portrait that no one ever bothered to repair.
Far from the watchful eyes that reported back to their mother.
It was safe.
The only safe place the brothers had ever had.
Back then, Regulus had still smiled around Sirius. He would sneak out of the Slytherin dorms late at night, small and serious and shivering in his dressing gown, to meet his brother here. Sirius would bring chess, or sweets, or silly stories about James’s disasters in Potions class. And Regulus would listen, and nod, and laugh sometimes.
Now, Sirius wasn’t sure that boy still existed.
He’d set out the chessboard the moment he arrived, arranging the pieces just as Regulus liked them. Black side facing the door, king and queen already in play, not hidden behind the pawns. It had been their thing, ever since Regulus was little. Something about knowing the game had already started made him feel more in control.
Sirius paced around the table, restless. His boots whispered across the stone floor, brushing through the dust that had settled thick since their last visit. A wide ring formed around the chessboard from his circling.
Minutes passed. Then hours.
He’s just late , Sirius told himself. He had to sneak away from the others. Maybe Slughorn stopped him. Maybe he fell asleep. Maybe—
But even as he listed excuses in his head, he knew.
Regulus isn’t coming.
It was nearly one in the morning when he finally let himself believe it.
Regulus always came. Even when he was tired, even when he was furious, even when he didn’t speak a word the whole time.
Sirius was the one who messed things up.
Sirius was the one who chose his friends over his brother, again and again.
He regretted that now.
With a hollow sort of ache in his chest, Sirius knelt beside the table and began packing up the chess set. Each piece fit smoothly into its place, polished from years of use. The quiet clinks echoed in the room like a lullaby, like the sound of childhood folding itself away.
Still, Sirius kept listening for footsteps in the hall.
For the creak of the classroom door.
For Regulus, who had always come before.
When every piece but one was tucked into the velvet-lined case, Sirius hesitated.
The black king sat alone on the board, small and weighty, carved from onyx.
Sirius stared at it for a long time. Then he reached into his pocket and pulled out a bottle of nerve tonic. The sort of thing he’d never admit to keeping, even though he still used it himself more than he liked to admit.
Then, parchment. He scribbled a note with fingers that trembled.
Little King,
The potion will help with the shaking.
Talk to me.
Your brother.
He set the letter on the table beside the nerve tonic and the black king, aligned just so. A message only Regulus would understand.
And then Sirius stood.
He didn’t look back as he walked toward the door. Didn’t let himself linger, though his body begged him to wait just a little longer.
Just in case.
His eyes stung, but the tears didn’t fall. Not yet.
They waited until he was back in Gryffindor Tower. Until he pulled back the curtains of James’s bed and crawled inside without a word.
James lifted his comforter silently, without asking any questions.
Sirius buried himself in his best friend’s arms and sobbed. Loud, shaking, ugly sobs that cracked open something he had been trying to hold shut since the start of term.
And James, the excellent friend that he was, didn’t even say
I told you so
.
Sirius was supposed to eat breakfast with the team on game days. It was tradition. But one pleading look from Sirius, and James just sighed.
“Fine. I’ll grab you something. But don’t be late to practice,” he warned, already swinging his legs out of bed. “I will make you run laps.”
James was using his Captain voice, but his eyes were too soft for Sirius to believe him.
Still, Sirius hurried anyway.
It took him less than ten minutes to make his way back to the classroom. The door creaked open like it always did, loud in the quiet morning.
At first glance, it looked untouched.
The dust hadn’t been disturbed much. The table looked the same.
But Sirius knew how to look closer.
The potion bottle was empty.
His note was gone.
And most importantly, the black king was no longer on the board.
In its place sat a single piece. A pawn.
Black. Simple. Unassuming.
Sirius laughed, sharp and wet, despite the tears still slipping down his cheeks.
Regulus had come.
Not while Sirius was there. Not to speak. Not to let himself be seen.
But he had come.
His little brother was still behind the mask somewhere. Still reaching out.
Because Sirius remembered that conversation.
They had been playing chess. Not well. Regulus had been too young to understand the rules, and Sirius hadn’t cared enough to enforce them. He had just started astronomy lessons with his tutor and was rambling about constellations between moves.
“You are Regulus,” Sirius had said proudly. “Heart of the lion. It means Little King.”
Regulus had been holding the black king piece in his hand at the time. He looked down at it, thoughtful.
“If I am the king,” he asked, “what piece are you, Siri?”
Sirius had scanned the board quickly before grabbing a pawn.
“I am a pawn,” he said. “Because I will always protect you.”
Regulus’s small face had gone terribly serious.
“Promise?”
“I promise, Reggie.”
Sirius had meant it. Meant it with every bit of his heart.
But he had broken that promise.
He hadn’t protected Regulus.
He had left.
And now Regulus was hurting.
Sirius arrived late to practice.
James took one look at his puffy eyes and gave a small nod.
“Get your kit on, Black.”
Sirius smiled softly. James was such a softy when Sirius cried.
Still, he didn’t push his luck. James might be kind, but he still wanted to win.
Sirius dressed quickly and splashed cold water on his face before jogging out to the pitch.
He was in the air before James could finish giving orders and settled into his drills without a word.
Sirius loved Quidditch.
He loved the rush of air against his face, the speed of it, the clean crack of the bat striking home.
Up here, there were no voices, no letters, no cold silence from across the Great Hall. Just movement and wind and muscle.
Practice continued uneventfully until the next team signed up for the pitch arrived.
Slytherin.
Green robes flew out in perfect sync, a tight formation that made James mutter something under his breath.
Sirius didn’t need to look hard to find Regulus.
There he was, hovering above the grass like he had been born on a broom.
So graceful it almost looked effortless.
But Sirius knew better.
He remembered the early lessons.
The way Regulus used to cling to his broom like a wet cat, shaking with fear.
He remembered the lesson where their mother had cursed Regulus’s hands so he couldn’t grip the broom, forcing him to fly without holding on. Telling him he would learn better that way.
He remembered the fall. The sickening thud. The crack of a bone breaking.
And the day after, when Walburga refused to heal the injury as punishment for being clumsy.
He remembered Regulus crying at night, not from the pain, but from the shame.
Sirius used to sneak him out after dark. Sit him on a broom, snug between his arms, and fly slow circles over the lawn.
Holding him tight.
Showing him how to fly without being afraid.
Sirius wondered if Regulus remembered too.
Because Regulus still didn’t look at him.
Not once.
Not even as their teams passed each other mid-air.
Sirius visited their room every morning and evening, but there wasn’t another sign from Regulus.
No scribbled notes.
No chess pieces left behind.
Just dust. Just silence.
It was another two weeks before Sirius finally spotted him alone on the map.
Regulus.
Perched in the Astronomy Tower.
Sirius was out of bed and moving before he had time to think at all.
“Padfoot?” James’s sleepy voice broke through the dark.
Sirius froze halfway to the door. It was well past curfew. He couldn’t just sprint through the castle chasing after his brother.
“He’s alone. I need to talk to him.”
He didn’t have to explain who he meant.
James blinked once, then pushed himself up on one elbow.
Take the cloak.”
Sirius whispered a thanks and grabbed the invisibility cloak from the foot of James’s bed. He pulled it over his shoulders and slipped into the hallway, moving as quickly as he dared.
His heart pounded in his chest as he climbed the stairs.
He prayed silently, to anyone who might be listening, magic or otherwise, that Regulus would still be there. That he hadn’t imagined the dot on the map. That he hadn’t lost his chance again.
Someone must have heard him.
Because when Sirius reached the final flight of stairs, he heard a voice.
His brother’s voice.
“I hate this, Siri.”
Regulus’s voice cracked on the name.
“I miss you so much. I want to let you hold me again. I need you.”
Sirius froze.
He glanced down, confirming he was invisible, and continued creeping up the stairs.
Who was Regulus talking to?
When he reached the top of the tower, Sirius paused in the doorway.
Regulus was alone.
He sat at the edge, head tilted toward the sky, arms wrapped around himself.
And he was still speaking.
“It’s better this way,” he whispered. “I couldn’t stand it if you hated me.”
The moonlight spilled across his face, cold and silvery, catching on the tear tracks running down his cheeks.
He hadn’t even noticed Sirius.
Because he wasn’t talking to anyone.
Sirius silently sat down, only a few inches away, careful not to let the cloak brush his brother.
“I love you, Sirius,” Regulus choked out.
Sirius looked up at the sky, following his brother’s gaze.
High above, a faint star blinked back at him.
His own star.
Regulus was sitting in the Astronomy Tower, crying under the stars, and speaking to Sirius . Not the boy. Not the brother. The constellation.
Sirius couldn’t take it.
He pulled the cloak off in one smooth motion.
“I love you too, Reggie.”
Regulus practically jumped out of his skin.
His eyes went wide.
Confusion.
Fear.
And for just a breath, hope.
Then the mask dropped into place like a slammed door.
“Why are you out of bed after curfew, Mr. Black?”
His voice held none of the emotion Sirius had heard only seconds earlier.
“Don't do that, Reggie,” Sirius said gently, reaching out to touch his brother’s tear-stained face.
But Regulus pushed himself up before Sirius could make contact.
“Do not refer to me as that. Ten points from Gryffindor for being out after curfew. Go to your common room.”
“You’re out after curfew,” Sirius muttered, his worry fraying into something sharper.
“I am a prefect,” Regulus replied coolly. “I am doing my rounds.”
“Oh, and here I thought you were crying and talking to my star about how much you missed me,” Sirius snapped.
Regulus’s jaw tensed. His expression didn’t change.
“That will be another ten points, Mr. Black. Or should I call you Mr. Potter?”
The words hit like a blow.
A line in the sand.
A reminder that Regulus no longer saw him as a brother.
A reminder that Sirius had left.
“Walk me to my dorm?” Sirius asked softly.
Regulus’s eyes didn’t soften in the slightest, but he gave a single nod.
“I do not trust you to return straight to your dorm.”
That made Sirius smile.
Regulus was a peculiar boy, but to Sirius, that didn’t sound like duty.
It sounded like he wanted to come.
They walked in silence. Regulus followed a step behind as they moved down the tower stairs. He ignored every word Sirius spoke.
It reminded Sirius of when they were younger.
He was eight. He had broken Regulus’s favorite toy, a sleek little enchanted phoenix that flapped its wings when you whispered to it.
Regulus didn’t speak to him for three full days.
It had taken Sirius insulting his height to get a reaction out of him.
Ten years later, insulting Regulus seemed like a terrible idea.
He knew a lot more hexes than he did at six.
But Sirius didn’t care.
He would take anything Regulus gave him.
Anything but cold silence.
Even a detention-worthy glare.
“You know, it’s way easier to relax if you take the stick out of your ass,” Sirius offered conversationally.
Regulus’s mask didn’t crack.
Not even slightly.
“Just a suggestion,” Sirius shrugged. “You know, if you ever decide to be anything other than Mother’s little puppet.”
That got a reaction. Just the tiniest twitch of Regulus’s wand hand.
I win.
Sirius grinned.
“What? Do you not want to be their perfect heir?” he gasped, dramatically. “Two blood traitor sons will kill her.”
Regulus finally spoke.
“Stop, Mr. Black. I am not having this conversation with you.”
“Oh, Merlin. You sound more posh every time you open your mouth.” Sirius was fully egging him on now.
“It’s not my fault I actually listened to Mother’s lessons,” Regulus snapped.
“Oh, yes. I remember.”
Sirius pitched his voice up into a mockery.
“Yes, Mother. Anything you say, Mother. I’m your perfect son, Mother.”
“Would you rather I was a rebellious brat like you?”
Regulus’s tone was rising now, sharp but not cold.
“Yes, I would.”
They were getting closer to Gryffindor Tower. Sirius knew he was running out of time. He needed this conversation to go somewhere.
“Well, I’m not going to,” Regulus said flatly. “I’m not like you, Sirius.”
It was the first time Regulus had spoken his name directly to him in months.
It shouldn’t have felt good.
It did.
Even if he was furious. Even if it was said like poison.
“You could be,” Sirius said quietly. “James’s parents would love to have you.”
“Stop, Sirius.”
“No, I mean it. You could come with us. Stay with us. Get out of that house.”
“ Stop! ” Regulus snapped.
But Sirius pushed. He always pushed.
“Please. Just come join us, Reggie. We’ll take you. I’ll take you.”
“ NO! ”
Regulus’s voice cracked as he shouted.
His wand fell into his hand with a twitch of his wrist.
He took a step back.
“I told you to stop.”
“I’m not going to stop,” Sirius said, voice steady. “I’m not going to stop asking because I’m not going to stop caring.”
He turned, fully facing his brother.
Regulus yelled again, louder this time.
“I’m never going to join you, Sirius!”
Then, with a sudden and violent motion, he yanked up his left sleeve.
Sirius fell to his knees.
Branded there on Regulus’s pale arm was the Dark Mark.
Black ink curled around the very arm Sirius used to hold every night when they were small.
The arm he clutched as he sang lullabies and whispered stories.
The arm Regulus used to wrap around Sirius’s middle when they flew together in the dark.
“Reggie?” Sirius whispered.
“No!”
The air between them shimmered, crackling with stray magic. The tension was thick enough to choke on.
“You don’t get to do that. You don’t get to pretend you care. Not when you left. Not when this is your fault.”
Regulus was furious now.
Not cold.
Not distant.
But truly, violently angry.
His face twisted with it.
His magic hummed just beneath his skin.
His chest rose and fell in ragged gasps.
And Sirius, still kneeling, frozen by the sight of that mark and the ache tearing through his chest, finally understood.
This anger, this fury boiling just beneath Regulus’s skin, it wasn’t their father’s cold disdain.
It wasn’t their mother’s precision and venom.
It was Sirius’s.
Hot, reckless, untamed.
Fire behind his eyes.
Skin itching to do something, anything, to make the feeling stop.
It was his .
And somehow, even as Regulus turned and stalked away, wand still in hand and sleeves shoved up like he didn’t care who saw, Sirius felt a twisted kind of pride.
Because for all that had changed, for all the things that had gone wrong, some part of him would always live inside his brother.
Some part of him would always be there.
Even now.
Even after this.