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You eyed the small bottle in your hand, quite impressed that you had managed to make the relatively tedious and complicated brew. The muddy liquid that sloshed around inside looked just like the picture in your potions textbook- though you would’ve liked a warning about the smell. Professor Sharp might’ve been proud of you, though he definitely wouldn’t condone a perfectly made potion being used for such a stupid reason…
Deek was used to you puttering around your potion stations in the Room of Requirement, never asking questions about the amount of Thunderbrew you made on a weekly basis, or why you needed so much of it. All of your adventuring in the Highlands kept your stores of ingredients full- no need to raid Professor Sharp’s classroom for Bicorn horns or Lacewing flies.
Even getting a piece of Ominis to add to the potion was rather easy; all you did was grab a loose blonde hair on the hood of his robes, pocketing it before he could notice. You’d carefully added it to the cauldron, making sure it wasn’t one of yours, and watched as it swirled around in the brownish mixture.
You were going to impersonate one of your best friends.
It wasn’t that difficult, you remembered, borrowing the identity of someone else with Polyjuice Potion. To get into the Headmaster’s office last year, you swallowed the disgusting mixture and disguised yourself as Professor Black. It was sort of fun—the taste of the concoction aside—until you started to turn back into your regular self.
You hoped that this would last as long as you needed it to, that you’d be able to find Sebastian and get him talking before the potion wore off. Plus, the idea of being Ominis was much more pleasant than inhabiting the body of your bumbling Headmaster.
Pocketing the small vial, you went down to the Slytherin common room to look for Sebastian, knowing Ominis was busy being distracted by Garreth somewhere. All it took to bribe the redhead was an hour in the Room of Requirement to work on his potions; away from the watchful eyes of Professor Sharp, your stores of Dubog tongues and Fluxweed Stems would likely be depleted by the time Garreth was done.
A potential mess to clean was worth it, and you’d be able to get more ingredients in no time. This was too important to you for anything to go wrong- and Ominis walking into himself would jeopardize your plan. You could only hope that whatever Weasley was bothering the blonde with would give you enough time alone with Sebastian.
Spotting the Slytherin boy curled up on one of the sofas near the fireplace, you hurried to your dorm room before Sebastian could spot you. You’d told both Ominis and Seb that you’d be busy working on a complicated potion in the Room of Requirement… if only they knew, you thought with a smile.
Shutting the door, you looked around the empty room and sighed with relief at Imelda’s absence. With no sign of your roommates there to witness the transformation, you took a deep breath and downed the potion. Once you’d stopped gagging, you felt the familiar tingle of your body as it shifted and stretched; Ominis was much taller than you, and you felt yourself growing to match his frame.
As you looked towards the mirror resting against the wall, Ominis's pale blue eyes met yours in the reflection. Getting over the shock of seeing his body instead of yours, you hurried out into the hallway and made your way towards Sebastian. The common room was relatively empty- you were grateful no one was around to see a boy exit your dorm room, especially Ominis at that. Mentally rehearsing for the conversation, you sat down on the couch next to Sebastian as calmly as possible.
“Ominis,” he smiled politely, scooting over to give you more room on the plush couch. Sebastian made no effort to close his book, but he directed his attention to you. “Back so soon?”
“Oh, yes,” you responded, “done with that thing I needed to do!”
“Okay,” Sebastian said, eyeing you suspiciously. His body stiffened, his eyes returning to his book. “You’re rather cheerful today.”
Ominis wasn’t that animated! Tone it down, you thought. Sound disinterested, look sullen!
You shifted so that your posture conveyed a disinterested air, giving you a bored look. The pounding in your heart slowed once Sebastian glanced over and visibly relaxed, seemingly convinced that his friend was acting normally after all.
“I’ve a question, Sebastian,” you started, eager to get along with your plan. Niceties be damned, you were a woman on a mission.
“I might have an answer,” he responded, looking over with curiosity. You mentally sighed with relief, knowing the best way to get your friend talking was to challenge him.
“When are you going to tell me what is happening with you and our… female friend?”
Sebastian laughed, and you wondered if you’d taken too direct a path. You didn’t have enough time for small talk; the potion needed to last as long as it took to get the information you required.
“I assume I know who you’re referring to,” he said, setting his book down for good. You had to stifle a smile- Sebastian’s interest peaked at your question.
As you confirmed his suspicions, speaking your name aloud for good measure, you watched your best friend smirk.
“We’ve talked about this, Ominis,” he laughed. “You begged me to stop last time.”
“Humor me,” you deadpanned, trying to channel your sarcastic friend with an eye roll. Hearing that Sebastian and Ominis had talked about you privately only added to your impatience, and you were more desperate than ever to know what Seb truly thought of you.
“You seriously want to go over this again?”
“Don’t make me regret it,” you sighed. “I just thought you’d be interested in the conversation I had with her earlier today.”
There, that sold it. Ominis didn’t seem like one for gossip, but the ever-curious Sebastian was distracted by the hint that his best friend knew something about you that he didn’t.
“Spit it out then,” Sebastian said suddenly. You watched as he tried to compose himself, acting like he wasn’t that interested in what you had to say. Of course, though, even you could tell that your best friend was anxiously anticipating your response.
“What would you like to know?” you asked, enjoying the knowledge that Sebastian was putty in your hands at that moment. The power shift was addictive- usually it was charming Seb who had you wrapped around his finger.
“What did she say about me? Does she feel the same?”
“Bold of you to assume the conversation centered around you, Sebastian.”
“Merlin, Ominis,” he responded with a huff. “Did you two speak about me?”
“We did.” He was hanging onto your every word. You were pushing your luck by dragging it out, but seeing Sebastian so flustered and unlike himself was endearing to you. He so rarely let his insecurities peak out from underneath the aura of confidence that constantly surrounded him.
“And?”
“Well, do you love her?” you asked directly, not willing to divulge any of your true feelings. Love was a strong word, but if you were going to tell Sebastian how you felt, then you needed to know you wouldn’t be rejected.
“You know I do, Ominis,” Sebastian sighed, running a hand through his hair.
Your heartbeat stuttered. Did Sebastian actually just admit it?
“How much?” you croaked out, no longer trying to hide behind Ominis's personality. You were too caught up in the idea of Sebastian returning your feelings to care about an accurate impersonation, your voice practically giving away your identity.
“I would go to the ends of the earth for her, Ominis. Sacrifice myself, give up everything I have.”
You sat there with tears welling up in your eyes. Willing them away, you played with the hem of Ominis's robe and avoided looking at Sebastian.
“So tell me, please,” he pleaded. “Does she feel the same?”
“Yes,” you mumbled, looking over at Sebastian. His brown eyes were searching yours, and for a second, you forgot that you weren’t in your own body. It was Ominis who was confessing your love to the boy in front of you.
“Merlin, that makes it worse,” Sebastian said, dropping his head down to his knees. Worse? How could loving him be a bad thing, especially now knowing that he felt the same for you?
“I don’t deserve her, Ominis. I never will,” he mumbled into his robes.
Deserve you? The boy could be so thick, you thought. Sebastian had no need to prove that he was worthy of your love, and you had no reason to doubt his loyalty and friendship to you. After everything that had happened the previous year—everything that you had done for him—the two of you were bonded for life. It was hard, the first few months. After stopping Sebastian from casting that horrible curse at his uncle and learning that it was Rookwood who had cursed his twin sister, you’d spent most of the summer together trying to heal. Solomon had taken Anne to London, leaving Sebastian with the guilt of losing the only family he had left.
In that time, you realized just how hard you had fallen for him, how willing you were to risk your own life for Sebastian. You were in love with your best friend, and it was maddening.
When the school year started, all you could focus on was Sebastian. You’d wondered how fighting a Goblin rebellion didn’t impact your studies as much as a silly crush on your best friend was. Not knowing if your time together meant the same to him was driving you insane. That was the desperation that inspired this idea, a way to figure out his feelings without having to admit yours first. Merlin, it got denser the more you thought about it. Just as Sebastian had let his obsession with a cure for Anne bring him deep into the depths of Dark Magic, you were letting your love for him make you manipulative and deceitful. It was almost ironic- maybe you two did belong together.
“You do deserve me, Seb,” you said softly.
“Me?” Sebastian asked, turning towards you suddenly. Your eyes grew wide at your mistake, the proverbial mask slipping as you lost control of the situation.
“No, no! I mean, her!”
Sebastian stared at you suspiciously, his eyes roaming your body. Oh Merlin, your nerves were on fire. You felt your legs shrinking under your robes, your jaw tighten and loosen. The potion was wearing off, the proof in Sebastian’s face. You were shifting back into yourself in front of his eyes, giving your ploy away.
You ran to your dorm room, your body rapidly transforming as you struggled to get out of Sebastian’s view. The head start towards the girls' dormitories gave you the chance to make it to your room before he reached it; you watched as he ran towards your closing door, slamming it seconds before he could reach you. Too embarrassed to cry, you slumped down onto the floor in silence. There was no coming back from your mistake; you’d been caught practically spying on Sebastian. It would be a miracle if he still spoke to you after this. His opinion on you—the feelings he said he had—was surely changed.
“Darling?” Sebastian spoke suddenly, making you groan. His tone was smug, a smirk evident on his face as he teased you with such an affectionate term. Was he seriously entertained by this?
“Don’t make me go back out there,” you responded glumly. He laughed at the soft thud of your head meeting the wooden door.
“Come out, pet. I promise I’m not mad.”
You couldn’t wallow in self-pity forever, not with Sebastian right outside your door. The stubborn Slytherin wouldn’t leave, and your grumbling stomach reminded you that it would be dinner time soon. Sighing, you slowly stood up, took a deep breath, and opened the door. Your best friend stood there grinning, his face beaming as he laughed once again. You tried to push him out of the door frame so that you could leave, but his larger frame blocked yours.
“I’m a fool, Sebastian!” you huffed, avoiding his seemingly mocking gaze. Although you deserved some humiliation for trying something as ridiculous as Polyjuice Potion, it hurt to see him act callously while you felt so guilt-stricken.
“Well, yeah.”
You rolled your eyes, trying again to push past him. Sebastian let you walk for a few steps before stopping you in the hallway, gently pushing you against the wall. You were trapped by his arms on either side of you, and the closeness of the compromising position would’ve made you head spin had you not been so mortified.
“You realize what happened, right?” he asked softly, his smile less superior. You met Sebastian’s brown eyes, feeling a blush creep up your neck- Merlin, you were a goner for him. Was it really true that he could say the same thing about you?
“I made myself look like an idiot?” you tried, giving him a remorseful look. His smile deepened, the corners of his mouth reaching his eyes.
“Seems fair that our roles switched at least once,” he said, getting a small giggle out of you.
“I’m so sorry, Seb, I shouldn’t have tried to trick you.”
“You didn’t trick me, though,” he said, “I knew the second you sat down on the couch.”
The confession made your face hot; Sebastian snickered as the realization hit you that he was playing along the whole time. Maybe you weren’t as convincing as you thought…
You pushed him playfully, despite still feeling shameful. He’d let you sit there the whole time and make a fool of yourself- though it was probably warranted. You shoved down the thought that he was lying the whole time, putting on a show instead of divulging his true thoughts…
Sebastian looked down at you, finally noticing how close you were to each other; his freckled face reddened, and a shy smile replaced his smirk. You’d rarely been in each other’s proximity to that degree, especially not in public. Even though it was tempting to close the gap between your bodies, Sebastian let his arms fall to his sides, giving you room to move away from him if you wanted to. There would be other times for closeness- in places more private than your common room, of course.
“It would’ve taken me ages to work up the courage to tell you myself,” he said softly. “I was too nervous to bring up a courtship when I thought you only wanted friendship.”
Your heart fluttered, butterflies swirling around in your abdomen.
“You want to court me?” you asked hopefully, then remembered what you had done. “Even after this?”
“Especially after this,” he admitted, laughing. “You must be madly in love with me to impersonate Ominis of all people.”
Sebastian looked proud. Who knew the Hero of Hogwarts would resort to Polyjuice Potion to trick him into admitting his feelings for her? Luckily for the two of you, Sebastian was just as smitten as you were.
“Should I have turned into Puffskein Duncan?” you asked with a laugh. “I assumed you’d share your secrets with Ominis.”
“Now you get to share the new one.”
“And which secret is that?” you asked.
“That we’re courting,” he said, grinning.
“We’re courting, are we?” you said teasingly. You beamed at the thought of being tied to Sebastian in that way, the dates and love notes in your future.
“It’s the least you can do,” he said, folding his arms across his chest with that confidence you were so fond of.
“Oh really?”
You mirrored his gaze, relishing the fact that you two were able to slip back into your typical banter with ease- despite your feelings now being known to each other. If anything, the reassurance that his flirting wasn’t empty made you feel bolder.
“You did scheme your way into asking me if I love you.”
“And do you?” you asked hopefully, wanting him to say it to your face, not Ominis's. Sebastian looked at you thoughtfully.
“I’m in love with you, darling.”
---
“You did what?” Ominis shouted, his voice echoing off the walls of the Undercroft. It didn’t help that the two of you had practically cornered the blonde on his way out, sitting him back down so you could make your confession.
“I asked her to marry me,” Sebastian said proudly, grabbing his hand in yours. A small knot of twine was tied around your ring finger- it would have to do until Sebastian could get to a jewelry maker after graduation.
You beamed at your fiancé, entangling your fingers with his. After courting for the rest of your sixth year— and the entirety of your seventh—the two of you were more than ready to take this next step together. Sebastian was going to be in Auror training during the summer, and you’d be working at St. Mungo’s as a junior healer; the two of you would fix up the abandoned Sallow home in Feldcroft to move into after your wedding. Ominis tried to act indifferent to the news, but his smile betrayed that he was overjoyed for the two of you. Even if you did a terrible job impersonating him that one time…
Since that day, your love for Sebastian had grown stronger than you thought possible- though you didn’t let it impair your judgment anymore. You two were about to embark on your futures together, the life with him you had dreamed about was becoming a reality.
All because of some silly potion.