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Sirius Black woke before the castle did.
The scarlet hangings of the four-poster bed were the first things he saw. For one blissful second, Sirius basked in the victory. He had defied the Black tradition and slept in a tower instead of a dungeon.
He was a Gryffindor.
The thought made him giddy.
He sat up so suddenly the bed creaked, heart pounding, biting back a laugh of joy so he wouldn't wake his roommates. The dormitory was silent, save for Peter's light snoring and the steady, rhythmic breathing of James and Remus.
Sirius had far too much energy to stay in bed.
He knew he wouldn't fall back asleep, not with excitement buzzing under his skin. So he hopped down, bare feet hitting cold stone. He began to straighten his sheets, more out of restlessness than responsibility.
That was when he found something beneath his pillow.
A piece of parchment.
Frowning, Sirius unfolded it, squinting in the dim light. The handwriting was oddly familiar—unmistakably his at first glance, yet slightly off. More mature, maybe?
Sirius,
If you're reading this, it means I managed to do it.
I'm seventeen now. And everything is ruined for me.
Sirius sank back onto the bed, his grin vanishing, replaced by a sharp twist of confusion and suspicion.
I finally did what we've been waiting for since you were eight and hiding in the library, hoping Mother would forget you exist.
The soulmate ritual.
You've spent nine years wondering if our other half exists. He does.
His name is Severus Snape.
The dormitory seemed to tilt.
Severus Snape?
The greasy-haired boy from the train. The one who had sneered at Sirius, bristled at everything James said, and looked like he thought he knew better than everyone else.
Sirius swallowed.
I know what you're thinking. I thought the same thing. I thought it had to be wrong. A joke. Fate being cruel.
But it wasn't.
By the time I understood that, it was already too late.
Six years too late.
His fingers tightened around the parchment.
I assumed he was irredeemable simply because he was a Slytherin. I made his life miserable. Now he won't look at me with anything but hatred and disgust.
You've already had a bad start with him. I know. I remember.
But listen to me carefully: it isn't irreparable yet. Not like it is now.
You still have time. Please—fix it.
For yourself. For us.
He'll be worth it.
Sirius Black
1976
Sirius sat there long after the letter ended, the parchment trembling slightly in his hands.
This had to be a prank.
It had to be.
He scanned the dormitory, heart hammering against his ribs. Was James awake? Was someone watching him?
But no one knew about the book.
No one knew about the soulmate ritual. In the wizarding world, the idea of The One was dismissed as old wives' tales, or soft-headed sentimentality.
No one knew how Sirius had clung to the idea of unconditional love after he'd found that book in the restricted stacks of the Black family library. The one that said soulmates weren't guaranteed—that most people never had one at all, which was exactly why most people claimed they were a myth.
But if you did—
You would never feel alone again.
The feeling of being whole. Of being understood without words. Of being loved without conditions.
The book described a ritual to determine one's soulmate—if they had one—which only worked for witches and wizards of age.
Sirius had believed it. Memorized it. Clung to it.
He had promised himself that when he turned seventeen, he would finally prove that he was not unlovable.
On the worst days, he whispered to himself that somewhere, someday, someone would look at him and accept all of him.
And now—
Now the universe was telling him that person was Severus Snape.
His first instinct was to laugh. His second was to tear the letter in half and pretend he'd never seen it.
There was no way his soulmate was a Slytherin. They were all dark and evil and—
But his future self had thought the same thing.
And his future self had said Severus would be worth it.
If there was even a chance this was real, if there was even a fraction of truth in it, Sirius couldn't afford to be reckless.
He couldn't afford to be wrong.
Sirius's mind wandered for the rest of the morning, through breakfast and the first two classes, his thoughts looping back to the letter no matter how hard he tried to focus. The name Severus Snape echoed in his head and he could barely hear anything else.
It wasn't until Gryffindor and Slytherin shared Charms that his attention snapped sharply into place.
Then he couldn't look anywhere else.
Sirius watched Severus from across the classroom, studying him with an intensity that bordered on obsession. He tried to match the boy from the train with the one in front of him, who was listening to the lecture with almost hungry attention. He noticed the way Severus relaxed, only slightly, when Lily Evans leaned over to whisper something to him. His expression softened. His mouth twitched into a rare smile.
That, more than anything else, gave Sirius hope.
Severus was different with her. Kinder. Open. Capable of warmth.
And Sirius had learned Lily Evans was a Muggle-Born Gryffindor—combination of two things an evil Slytherin would despise.
Maybe his future self was right. Maybe Severus wasn't irredeemable simply because he was sorted into Slytherin.
When the bell rang and students began to file out, Sirius hesitated, then followed at a distance, heart pounding. He watched Severus and Lily walk side by side until they reached the corridor junction, where Lily waved and headed off in a different direction.
Sirius swallowed.
Now or never.
"Snape," he called, before he could second-guess himself.
Severus stopped and turned slowly. His eyes narrowed immediately, flicking past Sirius as if searching for an ambush that hadn't materialized.
"What do you want?" he asked coldly after not finding any visible threats.
Sirius opened his mouth and nearly snapped back something easy and familiar and sharp.
Instead, he took a breath.
"Look," he said, forcing the words out evenly, "I was a prat yesterday. On the train. I know we got off on the wrong foot, but… maybe we can start over?"
Severus stared at him.
The silence stretched, thick and uncomfortable.
"Is this some kind of joke?" Severus finally asked.
"No," Sirius said quickly. Too quickly. He forced himself to slow down. "I mean it. I'm not… I'm not looking for a fight. I just want us to be... friends."
Suspicion crept across Severus's face like a shield snapping into place.
"And why," Severus drawled, "would you want to be friends with someone who is neither brawny nor brainy?"
The sneer stung more than Sirius expected.
He winced, swallowing the first three responses that leapt to mind. He tried, really tried, to look sincere.
"I shouldn't have said that," he said quietly. "Or called you names. I was trying to look cool, and I—" He grimaced. "I shouldn't have done that at your expense."
Severus studied him for a long moment. And Sirius tried his best not to fidget under the intense gaze.
Sirius wondered what he saw. His soul, maybe?
"I accept your apology," Severus said eventually. "But we are not friends."
Then he turned and walked away.
Sirius watched him go, shoulders tight, and let out a slow breath.
He'll be worth it.
Sirius repeated it like a mantra, convincing himself not to give up, no matter how difficult Severus was being.
It was a grueling exercise in patience that no one, least of all himself, thought Sirius was capable of.
The initial weeks were a cycle of cold rejections and sneering dismissals. Severus was a fortress of thorns, constantly waiting for the "punchline" to Sirius's sudden change of heart. Sirius had to finally learn restraint, something he'd never managed with Walburga; he bit back every instinct to bark an insult when Severus was particularly difficult, and he became an expert at redirection. He steered James away from Severus, subtly shifting the Marauders' focus toward "the truly evil ones"—the bigoted Slytherins who made Severus's life in the dungeons a trial.
The turning point wasn't Severus, but Lily.
After a month of watching Sirius hover at the edges of their lives like a persistent shadow, she saw what Severus couldn't: that Sirius wasn't setting a trap. When she passed Sirius in the Gryffindor common room, she leaned over and whispered, "Keep trying, Sirius. He's difficult, but he's worth it."
Hearing his own mantra echoed back to him from her lips felt like a divine confirmation.
With Lily acting as his champion and vouching for his intention, the ice around Severus finally began to thaw.
Severus stopped assuming malice where there was only clumsiness. He stopped bracing for the inevitable betrayal. And Sirius noticed, in small ways, that Severus had rules for everyone else, but somehow Sirius kept slipping through them.
By their fifth year, the impossible had happened: they were a fixture.
The Slytherins grumbled but remained hands-off, cowed by Sirius's status as the Black heir and what he was capable of doing when he stood beside either Severus Snape or James Potter. And with Lily being another defender of Severus, they kept the peace in Gryffindor.
In the quiet pockets of time they carved out for themselves, Sirius realized the note hadn't told him the half of it.
Severus saw him—all of him—and accepted what he found without softening the truth to make it easier to swallow. He never offered empty reassurances or platitudes. When Sirius was being reckless, Severus said so. When he was running from himself, Severus named it. And somehow, it always felt like care rather than judgment.
Severus was the best friend one could hope for. He was darkly witty, fiercely loyal, and held Sirius to a standard of honesty no one else dared to. But he never made him feel small or falling short. He was the kind of friend who would defend you blindly once you earned his loyalty. Lily often said Severus was enabling Sirius.
They often sat together in the library, or cramped together in a hidden alcove, their shoulders brushing as they pored over books or talked about everything and nothing. Severus rarely initiated the closeness—but he never pulled away either. Except on the bad days, when he'd take one look at Sirius, and simply hold him, silently, without prompting. He anticipated Sirius's need before Sirius even realized them. He responded, more than once, to thoughts Sirius hadn't spoken out loud.
In those moments, Severus made Sirius feel like the most important person in the world.
Well—second most important. Lily still held first place, and Sirius told himself he could live with that. It was more than he'd ever dared hope for in the cold halls of Grimmauld Place. It was closer to the unconditional understanding he'd once dreamed of than anything he'd ever known.
There was just a small problem.
Sirius Black was hopelessly, terrifyingly in love.
It was an inconvenient truth he refused to say out loud because, for all his Gryffindor courage, he was a coward when it came to Severus.
At some point during their slow-burn bonding, before Sirius truly liked Severus for who he was, rather than the idea of who he could be, Sirius had reread the soulmate book and realized, with a jolt of relief, that the bond didn't have to be romantic. It could be platonic. Two souls destined to stand side by side. Brothers-in-arms.
That knowledge had comforted him then, for he couldn't imagine being in love with Severus at the time.
If only he knew how wrong he had been.
The fight started over nothing.
Regulus accused Sirius, again, of choosing his friends over his family. Of disregarding what he should truly value.
Sirius snapped back just as easily.
"Maybe you don't understand friendship," he said. The words came out sharp and heated. "Maybe you don't understand genuine affection at all. Not when you're still living by Mother's rules—still mistaking obedience for loyalty, mistaking approval for love."
Regulus scoffed. Sharp. Disbelieving. "And you do?"
"As a matter of fact, I do," Sirius answered without hesitation, his voice dropping, steady and certain. He felt a familiar, secret sense of superiority rise in his chest. "And unlike you, I know it's real. The universe said so. It's been proven by ancient magic."
Regulus went very still. The anger drained out of him, replaced by uncertainty and fear.
"Don't tell me," Regulus said slowly. "Sirius… don't tell me you're talking about Severus Snape."
"Well," Sirius said, crossing his arms, lifting his chin just a fraction, "you'd be right. Go on. Sneer. It doesn't change the fact that he's the one. It has been written in the stars."
Regulus didn't sneer. He deflated. He looked at Sirius with such raw, agonizing pity that Sirius felt the first real prickle of doubt crawl up his spine.
"Sirius," Regulus whispered, his voice shaking, "don't tell me you still believe he's your soulmate. It's been more than four years. I thought—" He swallowed. "I thought you'd have realized by now."
"Realized what?" Sirius asked. His heart gave a heavy, sickening thud.
"I was the one who sent you the note," Regulus said, the words spilling out now, thick with shame. "I was ten. You were leaving me. Then I heard about your sorting." He swallowed. "I remembered the things you said about Slytherins, and I just—I wanted you to change your mind. Even a little."
Sirius's mouth opened, but no words came out, like his mind couldn't decide which part of this to reject first.
"I knew you'd have made at least one enemy in Slytherin by the end of the night," Regulus continued quietly. "I asked Kreacher to get me a name."
Sirius shook his head, small and frantic. "No! It can't be. The handwriting—it was mine. It talked about the book. The library. Things no one but me would know."
"Your script wasn't hard to imitate," Regulus murmured, looking away. "Not when we had the same calligraphy lessons growing up." He hesitated, then added, softer, "And I was there that day in the library."
Sirius stilled.
"You were too busy hiding from Mother to notice me," Regulus said, his voice dropping even lower. "You always were. You are always too busy doing something else to notice me."
"You're lying," Sirius said. Even to his own ears, it sounded thin.
"I'm really not." Regulus finally looked up, his eyes burning. "You hated every Slytherin on principle before you even boarded the train. And I just wanted you to question that. I thought—if you could find the good in one of them, maybe you'd still see it in me when I eventually sorted there."
Sirius shook his head again, like he could physically dislodge the truth.
"I was angry and afraid and stupid," Regulus went on, the words tumbling out now. "I thought you'd figure it out quickly. And by the time I started Hogwarts, you and Snape were already best friends." His voice broke. "I thought you genuinely liked each other. I didn't know you were still holding on to the soulmate nonsense."
"I do genuinely like him," Sirius said.
But the words sounded small, fragile, and terrifyingly insufficient in the face of the earth-shattering truth.
"Sirius… I am really sorry," Regulus said. He looked truly contrite.
"Don't. Just—don't."
Sirius didn't wait for a response. He ran past him, racing for the library, his thoughts a tangled mess. He needed to talk to Severus. Severus was the only person who ever managed to make sense of the world when it stopped making sense to Sirius.
As he ran, the letter replayed itself in his mind, along with all the tiny doubts he had dismissed over the years. It had been vague in so many places. He'd believed it anyway—because of the things that were supposed to be his secrets, because he had wanted to believe it.
But now, thinking back, he couldn't imagine himself mastering temporal magic at seventeen. And if he really had been capable of writing to his younger self, wouldn't he have said more? Wouldn't he have explained more than just a name?
"Severus, we need to talk."
Sirius was panting when he reached the library. Severus took one look at him, said nothing, and quietly gathered his things before following Sirius out.
Sirius didn't speak the entire way. Once they were back in their alcove, he told him everything. The book. The ritual. The note—not from the future after all. And Regulus's confession.
But Severus's reaction wasn't what he expected.
Sirius had thought Severus would make it right again, like he always did when Sirius felt like the world was ending.
Instead, Severus stared at him in stunned disbelief—like he was looking at a stranger. Like he didn't recognize Sirius at all.
"So," Severus said finally, voice flat. "Our entire friendship. Five years. It was all based on a lie."
"No!" Sirius said immediately. "No, that's not—I stayed your friend because I wanted to, because you're brilliant and loyal and you understand me better than anyone—"
"But you started being my friend because of a note," Severus cut him off. "A fake note. You didn't actually want me at all, did you? You just wanted your destined soulmate. You would have done the same to any other Slytherin if they were the one you antagonized on the train, as long as their name was written on the note."
"I was eleven," Sirius said desperately. "I was stupid and narrow-minded. I thought everything was black and white. Gryffindor good and Slytherin bad. And yes, I probably wouldn't have given you a chance if not for that note." He swallowed. "But Severus, you have to know—once I actually got to know you, once you let me in—"
"Once I let you in," Severus repeated, and there was something sharp and wounded in his voice now. "You mean once I made myself vulnerable to you. Once I trusted you. I thought you were genuine, when you only thought some divine power had promised me to you."
"It wasn't like that—"
"Wasn't it?" Severus took a step back. "Let's be honest, Sirius. I'm not easy to be friends with. I never have been. I'm prickly and suspicious and I don't let people in easily. You know that. Everyone knows that. So tell me truthfully—if you hadn't had that note, if you hadn't believed I was your soulmate, would you have kept trying? After the first week when I was still suspicious? After the first month when I was still keeping you at arm's length? After the first year when your housemates were giving you grief and I didn't make it easy?"
Sirius opened his mouth. Closed it.
"I don't know," he admitted, and watched something crack in Severus's expression. "Maybe not. You're right, it was hard. You made it hard. Everyone made it hard. And I was just a kid who wanted to belong, who wanted James Potter to like me, who wanted things to be simple." His voice dropped. "So maybe… maybe I would have given up if I hadn't believed in the soulmate thing."
Severus laughed, sharp and bitter. "Well. At least you're honest now."
"But that doesn't mean what we have now isn't real!" Sirius pleaded desperately. "Yes, I approached you under false pretenses. Yes, maybe I wouldn't have pushed through without that belief. But Severus, I genuinely like you. I care about you for who you are, not because some ritual told me to. Does it really matter how it started if what we have now is real?"
"Of course it matters," Severus said quietly, and there was something devastated underneath the anger now. "It matters because I thought you wanted me. I thought you chose me. I thought you saw something in me and decided I was worth the effort. But you were just following instructions from a fake letter, waiting for the payoff. Waiting for me to fulfill some fantasy of your youthful dream."
"That's not fair—"
"You wanted unconditional love," Severus continued, voice tight. "But your affection was conditional. You only wanted to be around me on the condition—the false promise—that I was meant for you. That's not friendship, Sirius. Not even close."
"I haven't thought about you that way in a long time!" Sirius said, his voice breaking. "Yes, I approached you because of who I thought you could become to me. But I stopped expecting any of that the moment I actually started caring about you."
"Really." Severus's eyes were too bright now. "Tell me something, Sirius. Now that you know the note was a lie, what's stopping you from doing the ritual? You'll be seventeen in a year. You could find out if you really have a soulmate. The one magic actually intended for you."
Sirius blinked. "I… I haven't even thought about the ritual in years—"
"But you could," Severus pressed. "You believed in it for your whole life. You could do it on your seventeenth birthday. Or any day after that. You could find out the truth."
"I don't need to—"
"Why not?" And now there was something almost frantic in Severus's voice. "You wanted it so badly at eight. You believed in it for five years. You built our entire friendship on the hope of it. You wouldn't give up trying because that's what you wanted at the end of the tunnel. So why wouldn't you want to know?" He laughed again, bitter.
"Severus—"
"I can't do this. I can't be your placeholder while you wait for something better. Or be your consolation prize when the ritual disappoints you." Severus said, backing away.
He turned to leave, and something in Sirius snapped.
"Why do you care?" Sirius heard himself ask, his voice louder than he'd intended.
Severus stopped.
"Why do you care if I have a soulmate I might or might not fall in love with?" Sirius continued, his heart pounding. "Why does it matter if there's someone else out there? I never complained about being second to Lily, did I? I know you met her first. I know she'll always be the most important person in your life. I made my peace with that. So why do you care so much about this?"
Severus turned slowly, and there was something dangerous in his expression. "Don't—"
"Why not?" Sirius took a step forward. "You're angry that I might have a soulmate out there. You're angry that our friendship started because of a note. When I told you, repeatedly, that my feelings are real. So Severus, why? Why does it matter so much unless you—"
"Because I'm in love with you, you absolute idiot!" Severus shouted, and then stopped, looking as shocked as Sirius felt.
The words hung in the air between them.
"You're—" Sirius couldn't breathe. "You are?"
Severus closed his eyes. "I'm in love with you," he repeated, quieter this time. "I have been for… I don't even know how long. And it was all your fault. You approached me, persistently. And you acted like you cared, you acted like I mattered." He stopped, shaking his head. "And now I find out that devotion was built on a lie. It doesn't matter now."
"It matters," Sirius said, finding his voice. "Severus, it matters more than anything."
"No, it doesn't," Severus said bitterly. "Because you built our friendship on a lie. A lie that I fell in love with. And now that you know, you could go find your real soulmate. And I have to live with the fact that everything you gave me was just borrowed."
"That's not true." Sirius crossed the space between them. "I am in love with you too. And it wasn't because of the note."
"How can I believe anything you say now?"
"I… When I was eleven, I didn't want to believe you were the one, because I couldn't imagine being with you. Mind you, I was eleven and young and stupid. So I looked it up, and learned that soulmates could be platonic. Which I had believed our bond was. I fell in love with you while believing you would only see me as a friend."
Sirius took a breath before continuing, "That's me choosing you even when I believed you wouldn't choose me back. Not because of destiny. Not because of magic. Because of you."
"But if you do the ritual—"
"I don't care about the ritual," Sirius interrupted. "I don't care if there's some magical person out there who's supposed to be perfect for me. Because Severus, you're not perfect. You're difficult and prickly and you make everything more complicated than it needs to be. And I'm reckless and dramatic and I nearly ruined everything because I was too scared to tell you the truth."
"Your point being?" Severus asked, but his voice had lost some of its sharp edge.
"My point is that I don't want perfect. I don't want unconditional love from someone who has to love me because magic says so. I don't want easy. I don't want someone who clicks with me instantly because of some divine intervention. I want this—us, our history, every impossible thing we've gone through to stay friends. We know each other better than anyone because we took time to learn each other—not because of some magical bond. And I wouldn't trade that for all the soulmates in the world."
Severus was staring at him now, something fragile and hopeful in his expression.
"I thought you wanted a soulmate," Severus said, but he wasn't backing away anymore.
"I wanted proof that someone could love me," Sirius corrected. "I was eight years old and my mother made me believe that I was worthless, and I wanted to believe that somewhere out there, someone was meant for me. Someone who would love me no matter what." He reached out slowly, carefully, and took Severus's hand. "But you know what? That's not real love. Real love is conditional. It's choosing someone every day, even when they're difficult. Even when you're angry at them. Even when they mess up and tell you something five years too late."
"I'm still angry about that," Severus said, but his fingers curled around Sirius's.
"I know. You should be. We're probably going to fight about it for weeks."
"Months," Severus corrected.
"Months," Sirius agreed. "But Severus… I'm in love with you. I think I have been for years, but I was too scared to admit it. Too scared that you'd only ever see me as a friend, that you'd only ever love Lily, that I'd ruin everything by wanting more."
"I do love Lily," Severus said. "She's my first friend, but I'm never in love with her. How could I be, when I'm in love with my best friend?"
"Well, I am in love with my best friend too."
Severus was quiet for a long moment, studying Sirius's face looking for the truth.
"If you ever do that ritual," he said finally, "and you find out you have a soulmate, and it's not me—"
"I won't do the ritual," Sirius interrupted. "I already know everything I need to know. And honestly—I've already been lucky enough to find you. I don't think the universe lets someone win the same lottery twice."
Then he took a breath and looked into Severus's eyes and said with the most seriousness and sincerity, "Even if there is someone out there who’s magically destined for me, I’d still choose you. I'd always choose you."
"That's incredibly stupid," Severus said, but he was smiling now.
"Probably," Sirius agreed. "But we can't all be smart like you. That's why I need you."
Severus finally sighed and sagged, the tension bleeding out of him as he leaned forward and rested his forehead against Sirius's. "And I need you," he said quietly. "You have no idea how much."
Sirius's heart was pounding so loud that he thought he might go deaf.
Then Severus muttered, like the absurdity of the whole ordeal was too much, "I honestly don't know if I want to hex Regulus or thank him right now."
"Maybe send him a thank-you note," Sirius said almost absentmindedly, "and then poison his tea. Just a little." He hesitated, then whispered, "Can we not talk about my brother when I'm working up the courage to kiss you?"
Severus smirked for the first time that evening.
"Not if I kiss you first."
And he did.
Sirius never found out if he had a soulmate on his seventeenth birthday, after waiting for it since he was eight.
But he did find out what it felt like to kiss Severus Snape in their alcove at sixteen, after wondering about it for years.