Chapter 3
3. The Time James Stole Regulus’s Place in Sirius’s Life
(Family Heirlooms, Unwelcome Partners, and the Art of Pretending It Doesn’t Hurt)
The house had never felt so empty.
Regulus had grown up in a home carved from silence, where love was conditional and the walls listened more than they spoke. Where words were sharp-edged things, used as weapons or currency, but never freely given.
But this—this was different.
The silence now was hollow.
It sat heavy in his chest, pressing against his ribs, something suffocating in the stillness.
The second summer without Sirius.
Last year, Regulus had spent weeks pretending it was temporary. That Sirius was just…gone for a bit. That he’d come back when he got bored of playing rebel, when he got tired of pretending he didn’t belong here.
He hadn’t.
And this summer, Regulus knew better.
Sirius wasn’t coming back.
He had left for good. Had run off to the Potters like it had been easy. Like it had been nothing.
Regulus should have hated him for it.
Sometimes, he thought he did.
He sat in the dim glow of the study, fingers curled around the edges of his chair, jaw set as he stared at the ink-stained parchment in front of him.
It was a letter. A stupid, pathetic thing that he wasn’t sure why he had even written.
The words weren’t right. They never were.
He had rewritten it three times now, and it still wasn’t enough. Regulus exhaled sharply, fingers twitching. The ink on the page blurred as he stared at it, something bitter curling behind his ribs.
He didn’t send it.
With a sudden, sharp motion, he crumpled the letter in his fist and hurled it into the fireplace. Flames licked hungrily at the edges, devouring the ink, curling the parchment into blackened fragments before turning it to nothing but ash.
Regulus forced himself to lean back, ignoring the tightness in his chest. He had made his choice. He had stayed. That was the way things had always been.
And Sirius? Sirius had James Potter.
Because of course he did. Because James was always there, ready to take what should have been Regulus’s, slipping into the spaces Sirius left behind like he had always belonged there.
Regulus had watched it happen in real time.
James and Sirius, thick as thieves. James and Sirius, laughing too loudly at the Gryffindor table, making it look so bloody easy.
James had taken Sirius’s loyalty the moment they met. Regulus had seen it. Had known it would happen before it did.
And James hadn’t even tried. He had just existed, and that had been enough.
Regulus exhaled slowly, the weight of the house pressing down on him.
Outside, in the distance, thunder rumbled.
The storm was coming.
War was coming.
Regulus felt it pressing in, seeping through the walls, coiling in the air like smoke from a fire that had already started burning. It was in the whispered conversations behind closed doors, in the sharp glint of Mother’s eyes when she spoke of loyalty, in the way Father stood silent but expectant, waiting for him to step forward, to take his place, to fall in line.
Sirius had gotten out.
Had found a home somewhere else.
Regulus swallowed against the tightness in his throat.
Because he wasn’t Sirius.
Because no one had ever told him there was another way out.
Regulus let out a slow, measured breath, trying to push down the thought clawing its way to the surface, the ugly, unspoken thing he had never allowed himself to name.
But it was there. It had always been there.
A part of him—small, quiet, shameful—wished he had been saved, too.
But no one had come for him. So he stayed.
Because there was nowhere else to go.
And the storm outside raged on.
The Black family ring sat heavy in his palm.
A weight. A promise. A shackle.
Regulus stared at it, throat tight, the engraved crest glinting in the dim candlelight. It was solid, cold, an unspoken vow pressed into metal—an inheritance, a duty, something that should have felt like power but instead felt like a sentence.
He wanted to throw up.
"You’ll be of age soon," his mother said, watching him carefully, her voice smooth, expectant. "It is time you start carrying the responsibilities that come with our name."
His father hummed in agreement, lifting his glass as if this was nothing but ceremony, as if this wasn’t a noose being placed around his neck.
The Mark would come next.
It was assumed, inevitable. They didn’t need to say it out loud. Regulus could feel it hanging in the air, thick as the scent of old magic and dust. His fingers curled around the ring, but he didn’t put it on. Not yet.
It should have been Sirius’s.
The thought came unbidden, slipping through the cracks before he could stop it.
This had been meant for Sirius. He was supposed to be the heir, the one to carry their name forward, to stand in this spot, listening to Mother’s sharp-edged approval, feeling Father’s quiet expectation press in from all sides.
Regulus wasn’t supposed to be here.
Maybe that was why, before he could think better of it, the words slipped past his lips—soft, idle, so innocent he didn’t even realize his mistake until it was too late.
"Sirius was supposed to—"
The impact was instant.
The back of her hand cracked against his cheek, sharp and unrelenting.
His head snapped to the side.
His vision blurred for a moment, ringing with the sheer force of it, a searing line of pain splitting across his face.
Then, something warm—something sharp and wet dripped down his skin. Metal had torn into flesh. His mother’s ring.
Regulus stilled.
The air in the room had shifted, turned razor-thin, suffocating. Her face was furious. Not wild, not unraveled, not screaming like she did when she spoke of Sirius. No, this was something else.
Something cold. Something coiled tight beneath her skin.
"You will never speak his name in this house again," she said, voice like a blade against stone.
Regulus swallowed against the sharp sting in his cheek, the slow burn of pain blooming where her ring had torn into his skin. He kept his head down, gaze fixed on the table, on the polished wood reflecting the dim candlelight.
He didn’t argue. Didn’t flinch. Didn’t reach up to touch the cut, even as the blood burned against his skin.
His father just lifted his glass, swirling the deep red wine before taking a measured sip, like he had done a thousand times before, like nothing had happened at all.
Kreacher appeared at his side, quiet as a shadow, his gnarled hands placing a napkin near Regulus’s fingers, an offering, a plea.
Regulus ignored it.
The ring was still clenched in his palm, its weight pressing hard against his skin, the edges biting into his fingers.
Heavy. Unyielding. His, now.
Because Sirius was gone.
Because Sirius had escaped.
Regulus inhaled slowly, the air thick and suffocating, his chest tight with something unnamed, something too sharp to be sorrow, too hollow to be anger.
If he ran—if he left—
No one would stop him, either.
But no one would save him.
Because he wasn’t Sirius.
And he never would be.
The dungeons were colder than he remembered. The air was damp, the scent of brewed ingredients thick in the space between old stone walls, candlelight flickering off glass vials and brass scales.
Not that it mattered—Regulus had always been good at blocking things out, at shutting out distractions and keeping his focus razor-sharp. The Potions classroom had always been predictable, and he liked that. Brewing was methodical, structured. If you followed the instructions precisely, if you measured and stirred and timed things just right, the result would be what you intended.
People weren’t like that. Life wasn’t like that.
Slughorn’s voice cut through the murmurs of students settling in, his usual genial tone carrying an air of importance as he introduced the term’s coursework. Regulus had known he was ahead of his year in Potions—Slughorn had made that clear enough times—that’s why he was here, stepping into a sixth-year class.
He let the words wash over him, already flipping through his textbook, already absorbing the information before Slughorn even finished speaking.
It wasn’t until the professor clapped his hands together and started pairing them off that Regulus lifted his head.
“Black, Potter—you’ll be working together.”
Regulus went still.
A pause.
A too-long, tension-thick pause.
Then— “You’ve got to be joking,” Potter muttered under his breath.
Regulus didn’t bother responding. He just pressed his lips into a thin line and forced himself to breathe through his nose.
Of course. Of course. Because if the universe had a cruel sense of humor, it was one that always seemed to put James Potter in his way.
Slughorn, oblivious to the tension, was already moving on to the next pairings. Regulus dragged his chair back with a sharp screech and moved stiffly toward the workbench, ignoring the way James let out an exasperated breath before following.
They didn’t speak.
Didn’t acknowledge each other as they pulled ingredients from the cabinet, as they set up their cauldron, as the instructions appeared on the board in front of them.
It should have been fine.
Regulus could work in silence. He preferred it.
But James wasn’t silent. Not really.
Even when he wasn’t speaking, he was there, radiating restless energy, shifting in his seat, drumming his fingers on the table, watching.
Regulus focused on measuring out the ingredients, methodically precise, ignoring the presence at his side.
Ignoring the way James was still watching him.
His jaw tightened. “Are you actually going to help, or are you just going to sit there and breathe obnoxiously?”
James let out a low huff, rolling his eyes. “Relax, Reggie. I know how to make a damn potion.”
Regulus rolled his eyes at the nickname. “Could’ve fooled me.”
James’s mouth twitched—annoyed, amused, it was hard to tell. “You know, for someone who doesn’t talk much, you sure have a lot to say.”
Regulus ignored him.
Instead, he focused on slicing the knotgrass, steady hands moving with sharp efficiency, keeping his attention on the task in front of him.
The potion they were working on was a complex one—Draught of Peace.
A subtle irony.
A potion meant to calm the mind, to smooth over turbulent emotions, to settle unrest. And here they were, two people who had never known a moment of peace in each other’s company, forced to brew it together.
Regulus focused on the careful movements of his knife, slicing the knotgrass into even, precise pieces, each cut clean and measured. The cauldron beside them was already filled with water, beginning to bubble at just the right temperature. He reached for the powdered moonstone, letting the fine, shimmering dust fall between his fingers as he measured the exact amount.
James, for his part, was still doing absolutely nothing.
Regulus exhaled sharply. “If you’re just going to sit there, at least prep the Valerian root. It needs to be finely ground, not whatever half-arsed version you usually—”
He stopped.
James wasn’t looking at the ingredients. He wasn’t looking at the cauldron, or at the instructions on the board. He was looking at him.
Regulus realized it too late. The weight of James’s gaze settled on his face, lingering—not with the usual mockery, not with the sharp amusement that always lined their conversations, but with something different.
Something assessing.
“What?” Regulus snapped, tension curling under his skin.
James didn’t answer right away.
His gaze flicked lower, settling just below Regulus’s cheekbone. The scabbed-over cut. The thin, raw line, still healing, still visible despite his best efforts.
“Did you get hit with a Bludger over the summer or something?” James asked, his voice almost absent-minded, casual in a way that felt deliberate.
Regulus went still.
For a moment—just a fraction of a second—he didn’t react.
Then, smoothly, he resumed his work. “What are you talking about?”
James didn’t look away.
His gaze stayed exactly where it was, lingering over the cut with a frown, like he was trying to piece something together, like he was seeing too much.
Regulus resisted the urge to shift, to turn his face slightly away. He could already feel his pulse quicken, something sharp and defensive rising up in his chest.
James frowned deeper. “Looks fresh.”
Regulus’s grip on the knife tightened.
He had spent years perfecting control, making sure no one saw more than he wanted them to. But James had always been perceptive in ways that were inconvenient.
He wasn’t supposed to notice.
James tilted his head slightly, like he was considering pressing the topic further, like the words were right there on the tip of his tongue.
Regulus clenched his jaw. He refused to let him.
He dropped the knotgrass into the cauldron, watching as the potion turned the exact shade of pale blue it was supposed to.
There was a pause, a moment where Regulus could feel James debating whether to push.
Then, suddenly— “You’re stirring too slow.”
Regulus blinked, thrown off for half a second before James reached forward and took the spoon from his hands, adjusting the movement, stirring in smooth, practiced motions.
Regulus narrowed his eyes. “I was doing it fine.”
“Sure, if you wanted it to curdle,” James shot back, but his voice was lighter now, something easy slipping into his posture.
Regulus inhaled slowly, grounding himself in the familiar rhythm of the potion, the predictable steps, the precision of it all.
James had changed the subject.
Whether out of strategy or instinct, Regulus didn’t know.
Didn’t care.
Because they were still working, still moving through the motions, and somehow—somehow—when the final stir was made, the potion sat smooth and silver-blue, textbook-perfect.
Regulus stared at it.
James leaned back, satisfied. “Huh,” he said, smirking just slightly. “Turns out we don’t make a terrible team.”
Regulus scoffed, reaching for his notebook. “Don’t push your luck, Potter.”
The next class should have gone like any other.
Regulus arrived early, as he always did. The dungeons were empty except for the distant echoes of bubbling cauldrons from earlier lessons, the scent of lingering ingredients steeped into the old stone walls. He slid into his usual seat, methodically unpacking his things—textbook, quill, parchment, a carefully arranged set of scales.
It was predictable. Structured. Controlled. The way he liked it.
Until, of course, James Potter ruined it.
Regulus had been in the middle of reading ahead—already scanning through the ingredients for today’s potion—when the seat beside him scraped against the floor.
His head snapped up.
James was sitting down.
Regulus stared at him. “That seat isn’t assigned.”
James didn’t even glance at him. He just set his bag down, arms slumping over the desk, far too comfortable for someone who was supposed to be his mortal irritation.
“Neither are the partners,” James said, stretching.
Regulus narrowed his eyes. What the hell was he doing?
Last lesson, Slughorn had paired them. This time, he hadn’t. This time, James had chosen to sit here, entirely unprompted, as if it were expected. As if Regulus wouldn’t question it.
Regulus shut his book with a slow, deliberate motion. “And yet, you’re here.”
James tilted his head, unbothered. “Well, you didn’t kill me last time, and we made the best potion in the room. Might as well not waste the talent.”
Regulus scoffed, crossing his arms. “What a ringing endorsement.”
James smirked. “I do what I can.”
Regulus let out a slow exhale through his nose, weighing his options.
He could tell Potter to leave. Could sneer, could turn to literally anyone else in the class, could make it clear that he had no intention of entertaining this ridiculous arrangement.
But then—Potter did have a point. They worked well together.
And Regulus hated that.
So instead, he turned his head away, opened his book, and ignored him.
James—insufferably, inevitably— took that as acceptance.
Today’s potion was a Wound-Cleaning Solution.
A deceptively simple one, used in most healing balms, brewed to dissolve infection and accelerate skin regeneration.
Regulus worked in calculated silence, measuring out ingredients with practiced ease. He liked Potions. Liked the precision, the lack of uncertainty. There was no room for error if you knew what you were doing.
James, for once, wasn’t entirely useless. He crushed the dried mallow roots into a fine enough powder without needing to be told, measured out the pomegranate juice without making a disaster of it.
James sprinkled the powdered roots over the bubbling liquid. Regulus frowned immediately. "Too fast," he said, reaching out to stop him. "You're supposed to add it gradually, or it turns murky."
James blinked, then peered into the cauldron. "Looks fine to me."
Regulus sighed, irritated, and grabbed a spoon. He stirred carefully, watching as the potion thickened, regaining its proper clarity. "If you rush it, the extract won't mix evenly. Try to pay attention."
James snorted but didn’t argue. He adjusted his approach, dropping the next ingredient more carefully. Regulus said nothing, but he noted it. James might be an idiot about most things, but when it came to learning, he watched. He adjusted.
And somehow, the potion started coming together perfectly.
James seemed to notice it too. "Huh," he muttered. "Didn't think it’d work."
Regulus let out a humorless laugh. "Imagine that. You following instructions actually works."
James rolled his eyes but didn’t take the bait. He kept working, focused, and—for a brief moment—there was no bitterness, no rivalry, no underlying tension.
Just a task. A shared objective.
It was fine.
Until James ruined it.
"You should use dittany."
Regulus blinked, barely processing the words. “What?”
James nodded toward him, entirely too casual. “For your cheek. It’ll help the mark heal faster.”
Regulus went rigid.
His grip tightened around the stirring spoon, fingers pressing against the worn wood.
James kept talking.
“Sirius used to—”
The words barely left his mouth before Regulus slammed the spoon onto the table.
The sound cracked through the space between them, sharp and unmistakable.
James stopped.
Regulus turned to him, jaw clenched so tightly he could feel the pressure all the way down his spine.
“Don’t.”
James’s brow furrowed. “Don’t what?”
Regulus’s voice was ice. “Don’t talk to me like we’re the same.”
James frowned, his usual cocky ease faltering for a fraction of a second. “That’s not what I— She is hurting you,” James said, quieter now, voice lacking its usual arrogance.
Regulus’s breath hitched.
James didn’t stop.
“The same way she hurt him,” James said, his gaze unwavering. “And I’m not going to pretend I don’t see it.”
Regulus’s pulse thundered in his ears.
Too much.
He was saying too much.
He forced a breath out, slow and measured, gripping the edge of the desk.
“This isn’t your concern.”
James didn’t look away.
“It should be.”
Regulus let out a bitter laugh, sharp and humorless. “Because you think you can save everyone, don’t you?” James’s jaw tightened. Regulus turned back to the cauldron, stirring sharply, the golden liquid swirling too fast. “You’re not as much of a hero as you think, Potter.”
James exhaled, slow and heavy, before leaning back in his seat.
“You know,” he said, quieter now, but not softer. There was frustration in it, something that teetered between exasperation and something else, something harder to name. “You and Sirius are the same.”
Regulus froze for half a second before forcing himself to keep stirring.
James kept going, undeterred.
“You both are fucking impossible,” he muttered. “He cares about you, you know? I know he does. He misses you more than he’ll ever admit. But he’s so—so bloody stubborn about it, always acting like he can take on the whole world alone. And you—” He let out a sharp, humorless laugh, shaking his head. “You’re exactly the same. Fucking Blacks.”
The words sat in the air between them, thick and heavy, like the steam curling from the cauldron.
Sirius misses you.
Regulus let the sentence roll over in his mind, dissecting it, breaking it apart like an ingredient he needed to understand before it contaminated the whole potion.
Why was James bringing this up?
Why now? Why at all?
His gaze flickered to James, sharp and searching. The usual bravado wasn’t there—no smugness, no teasing lilt in his voice, no attempt to get a rise out of him.
It was worse than that.
It was sincere.
Regulus hated that.
His grip on the stirring spoon tightened. “Sirius has you now.” The words were cold, detached, but the sharp edge beneath them was impossible to miss.
James sighed, rubbing his temple. “That’s not—”
Regulus cut him off. “So why are you bringing this up?”
James met his gaze, unwavering. “Because it matters.”
Regulus scoffed, a bitter sound. “To who? To you?”
James didn’t blink. “To him.”
Regulus clenched his jaw. “Sirius made his choice.”
Something flickered across James’s face—frustration, maybe. Or understanding. Regulus wasn’t sure which was worse.
“He still cares about you,” James said, as if it were that simple. As if the years between them, the unspoken things, the bruises hidden beneath long sleeves, could be so easily rewritten.
Regulus inhaled slowly, steadying himself.
His mother’s ring had split his cheek open. His father had watched it happen. His house was empty and rotting, and yet he stayed.
Sirius had left.
Sirius had James.
Regulus had nothing.
He swallowed down the thing curling in his throat, something he refused to name. “Then tell him to stop.”
James frowned. “Stop what?”
Regulus exhaled sharply through his nose. “Stop pretending there’s anything left between us worth missing.”
James stared at him. Long, unreadable.
Then, finally—he didn’t push.
He didn’t try to argue, didn’t try to fix it the way Regulus knew he wanted to.
Instead, he leaned back in his chair, letting the silence stretch between them.
And Regulus...
Regulus turned back to the cauldron, watching the potion swirl, clear and perfect, as if nothing had ever disturbed it.
But in his head, James’s words still echoed, sticking to his ribs like something he couldn’t quite scrape off.
Sirius misses you.
Regulus focused on his breathing, the steady rise and fall of his chest, grounding himself in the predictability of it.
James thought he could fix this.
James, who had never been left behind.
Regulus exhaled, slow and deliberate, pressing the tension back into the spaces between his ribs. He refused to let it surface. Refused to let James see anything.
“Drop it, Potter,” he said finally.
James studied him for a moment longer, something still lingering in his expression—something Regulus refused to look too closely at.
Then, finally, James nodded. He turned back to the cauldron, stirring the final ingredient in.
The potion shimmered, smooth and precise, a perfect execution of everything it was meant to be.
Regulus stared at it, something bitter curling in his chest.
Because potions followed rules. Ingredients could be measured, steps could be followed, and if you did everything right—if you were careful, if you were precise—the outcome would always be what you intended.
But life wasn’t like that.
People weren’t like that.
And some things, no matter how much you tried, could never be undone.