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Regulus hadn’t planned to approach Sirius.
He told himself that repeatedly as he stood at the edge of the platform, fingers curled tight into the sleeves of his robes. But seeing Sirius—really seeing him—laughing freely, alive in a way Regulus had only imagined in secret, cracked something open in his chest.
He just wanted one word. One look.
Before courage could fail him, Regulus took a step forward.
Then another.
“Sirius?” he said quietly.
The name felt dangerous on his tongue.
Sirius turned, surprise flashing across his face—and then something harder slammed into place. Fear. Anger. Guilt twisted sharp enough to look like hatred.
“What do you want?” Sirius snapped.
Regulus flinched but forced himself to keep going. “I—I just wanted to—”
He didn’t finish. Sirius shoved him.
Not hard enough to send him to the ground—but hard enough to hurt. Enough to make Regulus stumble backward, breath knocked from his lungs, eyes wide with shock.
“Don’t,” Sirius hissed, fists clenched. “Don’t come near me.”
Regulus froze.
People were staring. Whispers rippled through the platform. Regulus felt twelve again, small and exposed and wrong for wanting anything at all.
“I’m sorry,” he whispered automatically, even though he didn’t know what he was apologizing for.
Sirius turned away like the sight of him burned.
Regulus stood there for a long moment after, heart pounding painfully against his ribs, before retreating into himself completely. By the time they reached the castle, something fragile inside him had already begun to fracture.
Regulus barely made it through the Sorting.
The hall felt too large, too loud, too bright. Every laugh ricocheted off the stone walls and straight into his skull. He sat rigid at the Slytherin table, spine straight, hands folded in his lap the way his mother liked—proper, controlled, invisible.
The food appeared in front of him in a rush of steam and sound.
His stomach twisted violently.
He told himself to eat. He really did. He lifted his fork, fingers trembling, and speared a potato. Halfway to his mouth, his vision swam. The smell—rich, overwhelming—made bile rise in his throat instead of hunger.
Later, he promised himself. I’ll eat later.
Across the hall, Sirius laughed too loudly at something James said. The sound cut through Regulus like glass. He didn’t look over. He couldn’t. Not when Sirius hadn’t spoken to him once since arriving.
Regulus’s hands curled tighter in his lap.
The lights flickered.
No—they didn’t flicker. He was.
The edges of the hall began to blur, sound stretching and warping as if he were underwater. His chest felt tight, breaths shallow and ineffective. He swallowed hard, suddenly aware of how fast his heart was racing.
Sit still. Don’t draw attention. Don’t—
Pain lanced behind his eyes. White-hot, blinding.
Regulus gripped the edge of the table as the floor tilted sharply to the left. Someone at the Slytherin table was talking to him—his name, maybe—but it sounded far away, distorted.
He tried to stand.
Bad idea.
The moment he shifted his weight, his legs buckled like they’d simply decided they were done. The world went dark at the edges, rushing inward.
The last thing Regulus felt was cold stone meeting his cheek.
And then—
Nothing.
Sirius heard the chair scrape.
Something in him went instantly, horribly alert.
He turned just in time to see Regulus pitch forward, body crumpling bonelessly to the floor.
“REGULUS!”
The shout tore out of Sirius’s throat before he could stop it. The Great Hall erupted into chaos—students shouting, chairs scraping back—but Sirius barely registered any of it. He was already running.
Regulus lay unnaturally still, lashes dark against too-pale skin. His lips had gone faintly blue.
Too pale. He’s too pale.
Sirius dropped to his knees, hands hovering uselessly for half a second before gripping Regulus’s shoulders.
“Hey—hey, come on—Reggie, look at me.” His voice cracked. “Please.”
Regulus didn’t respond.
Panic surged, hot and choking. Sirius pressed two shaking fingers to Regulus’s neck. A pulse—there, weak but present.
“Oh Merlin,” Sirius whispered, forehead dropping briefly to Regulus’s shoulder. “Oh Merlin, I’m here. I’ve got you.”
Madam Pomfrey arrived in a flurry of robes and sharp commands, pushing Sirius back just enough to examine Regulus. Her frown deepened immediately.
“When was the last time he ate?” she demanded.
Sirius opened his mouth. No answer came.
Because he didn’t know—and that knowledge hit him harder than anything else.
As they levitated Regulus onto a stretcher, his hand slipped free of Sirius’s grasp. Sirius lunged forward, catching it again, refusing to let go.
“I’m not leaving,” Sirius said fiercely, whether to Regulus or himself he wasn’t sure. “Not again.”
Regulus stirred faintly as they moved him, brow furrowing, breath hitching as if even unconscious his body remembered fear. Sirius leaned close, voice dropping to a broken whisper.
“You’re safe,” he said. “I swear. You’re safe now.”
James stood at the edge of the chaos, heart in his throat, watching Sirius clutch Regulus’s hand like it was the only thing holding him together.
And for the first time, James understood something with terrifying clarity: Whatever had happened to Regulus Black over the summer—it hadn’t ended when Sirius left.
Regulus woke slowly.
The first thing he noticed was warmth.
The second was pain—dull, aching, everywhere.
His lashes fluttered, vision swimming as white curtains and soft candlelight came into focus. The hospital wing. His throat tightened instantly.
I did something wrong, his mind supplied automatically.
He tried to sit up.
“Hey—no,” Sirius said urgently.
Regulus froze. Sirius was there.
Sitting far too close, eyes red-rimmed, hair a mess like he’d been running his hands through it over and over. One hand hovered uncertainly above Regulus’s arm, as if afraid to touch him again.
“I—” Regulus swallowed. “I’m sorry.”The words came out on instinct and Sirius’s face crumpled.
“Stop,” he said hoarsely. “Don’t say that. Don’t ever say that.”
Regulus blinked, confused. “I shouldn’t have—at the train—I—”
Sirius stood abruptly, pacing once like a caged animal before dropping back into the chair.
“I pushed you,” he said, voice breaking. “I hurt you. And then you collapsed and I—Merlin, Reggie—”His voice failed entirely.
Regulus stared at him, heart aching in a way that felt different from fear. Softer. More dangerous. “I just wanted you to say goodbye,” Regulus whispered.
Sirius covered his face with his hands.
“I thought if I stayed away, I wouldn’t make things worse,” he said. “I was wrong. I was so wrong.”
Tentatively, Regulus reached out, and this time, Sirius didn’t pull away this time.
Their fingers tangled—hesitant, fragile—and held. “I’m here now,” Sirius said, barely audible. “I swear. I won’t leave you again.”
Regulus closed his eyes, exhaustion pulling him under once more. But this time— He didn’t feel alone.