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When the door creaked open, Severus’ heart sped up and he smiled. So his plan had worked, and how easy it had been. Sirius Black must have been the thickest student to walk the halls of Hogwarts—but how lucky that was for him. It was easier to manipulate idiots. In this case, bright-eyed idiots who crept around after hours practically looking for trouble. Well Black was going to get all the trouble he could handle tonight.
When Black shut the door behind him, it made an ominous click when door met frame, and Black raised his eyebrows. A wrinkle began to form in his brow, and his lofty smirk fell only a millimeter but Severus could practically smell the nervousness on him. Severus’ wand nearly slipped from his hand, his palms slick with sweat and anticipation as he watched Black carefully from behind the black curtain.
“Incarcerous,” he hissed on a breath.
Black yelped as the ropes bound his arms to his torso, tripping him as they wrapped his knees together. He fell face-first onto the marble floor, and Severus bit back a laugh—perhaps he had broken his nose. All the better.
Black deserved to suffer.
Severus stepped out into view, his boots clicking sharply on the stone, and made his way to stand in front of Black’s wriggling form. Black arched his neck to look up, and upon seeing him, his mouth twisted into a hideous grin. His teeth shone fang-like in the dimly lit room.
“I should have known. Wherever something stinks of Dark magic, someone’s bound to find Snivellus Snape.”
Severus smiled back serenely, clasping his hands casually behind his back. “Dark magic? You mean my simple Incarcerous?” He knelt down on one knee and looked into those grey eyes, hoping desperate rage was bubbling within. “And I wouldn’t be taking that tone if I were in your position, Black. You need to rely on my mercy to get out of here.”
Black barked a laugh. “I’d sooner resign myself to being a dead man.”
Severus could hardly contain his glee, but he kept his breathing steady and smirked. “I have a little something else planned for us tonight.” Oh, that delicious spark of apprehension in Black’s eyes. “Would you like to know what that is?”
“I’m sure you’ll tell me.” Black swallowed. “You know, I told my friends I was coming here. They’ll come looking for me if I don’t come back.”
“No they won’t.”
Black’s lips parted as his breathing started to quicken.
“Stupid, Black. Very stupid to lie to me. Who do you think wrote the note?”
“Ja—” Realization dawned over his aristocratic features.
“See? Very stupid.”
“Let me go!” Black twisted in his bonds, thrashing his legs. The ropes around his knees didn’t budge an inch. “You’ll be sorry if you do anything to me, Snivellus! I’m not kidding, let me go. You will regret this, you slithering little snake!”
“Manners.” Severus reached into his pocket and pulled out the glass flask he had been carrying around all week. After months of preparation, he was finally getting his revenge. The potion was absolutely brilliant; liquid Imperius, he thought of it. This was certainly one of his best creations. “Well, you’ll develop manners soon enough.”
Even in the candlelight, Severus could see the red splotches of color on Black’s cheeks and neck as he eyed the flask in front of him. He knew the words on Black’s lips—What is that? What are you doing?—but he could also see the determined pride keeping Black from asking out loud. Still, his eyes said enough. The fear in them made Severus’ blood run faster.
The struggle to make Black drink almost resulted in spilling the potion all over Black’s robes, but it was easy enough to hold him down with the thick ropes doing most of the work. His fingers left angry red marks in Black’ cheeks where he had squeezed his mouth open. He had also pinched Black’s nose hard to force him to swallow.
There, it was done. Unless Black coughed the entire thing out, damn it. But he soon stopped and became very still.
Now, Severus had to test the effects.
“Look at me.”
Slowly, Black raised his head. He didn’t appear entranced. His gaze was neither hazy nor glossed over. He wore the same frown as before and if anything, it became deeper.
Hm… Perhaps the command was too mundane. Anyone could raise their heads and look up at someone, they didn’t have to be enchanted to do that. He had to try something much more direct, and for that he would have to release Black from his bonds.
If the potion hadn’t worked, Black would surely curse him within an inch of his life. Severus narrowed his eyes, trying to discern the answer from Black’s face. But he only looked angry and that was extremely unhelpful.
“Speak,” he said, as though commanding a dog.
“What?” Black snapped.
Again, very vague. What could he command to prove that Black was under his control, without resorting to releasing him just yet? “Address me as Sir.”
Black clenched his teeth, sucked in air between them. It seemed to take him forever to let it out, but when he did, he also faintly added, “Yes, sir.”
Spirals of lust erupted in Severus’ stomach and snaked down to his cock, which became instantly a little harder.
He realized he was grinning as pleased as a cat. “Very good.” With a flick of his wand, he released the Incarcerous. “Now get on your knees.”
For a moment it seemed like Black wasn’t going to do it, but then he dragged himself up and settled on his knees, facing Severus. His back was straight and his shoulders held back, and despite the natural subservience of his position Black managed to come off as arrogant as ever. Only Black could be on his knees and still give off the air of a lord. It drove Severus crazy. There was probably nothing he wanted more than to punch the smugness off of Black’s face, every single day that he saw him in the halls and in class. Especially that one day at the beginning of term.
“Do you even know why you’re here?” Severus asked. Why I so badly want to punish you?
Black raised his head but he kept his eyes to the side. “I think so.”
“You think so.” What an infuriating answer. Could Black really be that incredibly stupid? Was he so self-absorbed that he couldn’t even begin to guess? “You…”
“I kissed you.”
Severus scowled, despising that sharp and strange feeling in his gut. “You had no right to do that!” The feeling curled and settled, like a coil of warmth. He hated that treacherous feeling now and he had hated it then.
It had been the first week of the new term. They had been rather brutally fighting one moment, and the next Black had kissed him, right on the mouth. He remembered it as crisply as if it were yesterday, and he could almost still taste him. The smoke from the cigarettes Black snuck into school, the stain transferring to Severus’ lips and to his memory.
Snape had been forced to unwrap his hand from Black’s throat and let him go.
He had been humiliated. And not only outwardly, because Black had forced a kiss on him in front of all those people who laughed like it was just another one of Black’s big harmless jokes—no one seemed to care that it harmed Severus, of course—but inwardly humiliated as well. By that disgusting feeling.
Well he was going to show Black now. He’d learn the days he could terrorize Severus without consequence. And if Black thought kissing was so funny, he was going to have a laugh about this. Or perhaps not quite a laugh, and Severus counted on not.
“Take off your robes. And the rest of your clothes.” He tried to pretend he didn’t enjoy watching him peel every layer off, slowly exposing his pale skin, but he watched closely nonetheless. “Stand up and turn around.”
Black scowled, but he did as he was told. And Severus inhaled slowly to steady his heartbeat. The room burned hot like an overflowing furnace, and Snape wondered why the damn place didn’t realize he required a cooling charm.
He drew in a breath as he gazed upon Black’s arse. Curse him for having an athlete’s body when he didn’t even play Quidditch. His waist was trim and his thighs were lean, and each globe of his arse looked like it was just the perfect handful…
“Bend over.” This time, something deliciously vindictive washed over him and he got a thrill watching Black comply. Black rested his hands on his knees as he bent at the waist.
“You prick.”
“What was that?” Severus asked.
“I said, you’re a prick!”
“I thought I told you to address me as Sir.”
Black grumbled something incoherently, but then he complied with a barely audible, “Yes, sir.”
What a delicious thing to hear. “Now,” he said, his excitement rising, “spread your cheeks apart.”
“Bastard.” He seemed to exert a great amount of effort in resisting, but the potion had a strong hold and he was soon reaching back, one hand on each arse cheek, spreading them open. Then he stood still, holding the position.
Severus bit his lip. Black was his puppet. That knowledge, paired with the sight before him, made his body thrum with lust. His cock was definitely hard now, and Severus stroked it over his trousers.
“What a pretty… little…” He stepped closer to have a better look. Black’s entrance looked so tight. He wondered… “Put your finger in it. And remember to address me properly.”
Black’s back muscles tensed. “Yes, sir.” He inched one index finger closer, poking at his hole until he lined it up right. Slowly and with tentative motions, he inserted just the tip.
“Is it very tight?”
“Yes, sir.”
“Keep going.”
Black wriggled his finger deeper, millimeter by millimeter, and it occurred to Severus the process might be easier with some lubrication. Which meant he definitely wasn’t allowing him any.
Or perhaps he would.
“Stop, look at me.” Black turned his neck, blazing cheeks and all, and stared daggers at Severus. “Take that finger out and lick it.” Black raised his eyebrows. “Now!”
He never stopped looking Severus in the eye as he put his finger between his lips and sucked on it.
“That’s it,” Severus encouraged, unbuckling his trousers. “Get it nice and wet.” He worked on his zipper, pulling his cock out from the opening. Black didn’t even glance down at it, just continued to glare into Severus’ face. He knew what was coming. The potion didn’t erase all sentience quite like Imperius did. Which was all the better, as it must be disgustingly humiliating for him this way.
A line of drool began to drip from Black’s bottom lip.
“Enough,” Severus said, and Black pulled his finger from his mouth. “Go back to fucking yourself.”
Black had a much easier time of it with the added slickness, and he managed to fit his entire finger into his arse in one go. He pushed it in and out repeatedly, doing exactly as he was told, while Severus stroked himself and watched.
“You thought you were so clever.” He couldn’t help himself, the words started tumbling out. Perhaps it was the mind numbing feel of stroking his cock, or the rush of power he got watching this filthy display, but Severus felt both indestructible and out of control at the same time. “You have no idea what that kiss did to me, and you don’t care, do you?” He spread his precome over his shaft; he was almost ready. “Yes, handsome and clever Sirius Black… But look at you now.”
He stepped closer, swaying, though from his pointed desire or from the heat he was unsure. For a second he felt a roaring need to just stop. He was stepping up to an invisible brick wall.
In his mind it had always been an eye for an eye; one unwanted sexual advance for another. A fair trade in the realm of his fantasies over the last months. But maybe that was the thing: it only made sense in his fantasies. Maybe something was off in his estimation. Maybe his thirst for revenge, as well as his desire to squash the prickly feeling of softness toward Black that lived somewhere deep inside him, drove him to do something that was actually mad.
This was madness.
But he had come so far.
He could Obliviate the prat afterward. That would surely solve one problem. But could he erase his guilt?
Black looked back around again and caught Severus’ eye. The anger from before had changed into something else. He was waiting for Severus to do something. That something. Surely he was dreading it. Disgusted even. Then Severus realised there was one sure way to find out, and it was so obvious he didn’t know why he hadn’t bothered to notice earlier. He looked down at Sirius Black’s prick.
“But…” Part of him felt slapped, like once again, Black was coming out the winner. Severus couldn’t even lure him into a trap of humiliating revenge; Black had to go and enjoy it. His cock stuck up from its nest of curls, proud and strong as Black ever was. It taunted Severus, saying, there’s nothing a snivelling little bastard like you can do to ever break me, and all of this, even, was a victory for Black.
Severus fucking hated Gryffindors.
This one most of all. He scowled and checked his watch. If he had to guess, he only had about ten more minutes before the potion began to wear off.
“Listen here, Black. I’ve won, haven’t I?” Black stared at him. He was still fucking himself. That’s right, Severus had never told him to stop. A shiver of renewed lust ran through him, and he swallowed hard. “You’re under my command. I could make you do anything, just like that. I could fuck you if I wanted to and make you beg for it.”
Black sneered, his eyes glinting fiercely. “Then why don’t you?”
Severus’ opened his mouth but wasn’t sure how to close it again.
“You got me naked, you forced me to expose myself to you. You see that I’m hard. Why not just get it over with and end this?”
Could he actually want this to happen? “Stop doing that,” Severus murmured as he carefully considered Black, who pulled his finger out of his arse and went back to bending over and spreading. He struck such a gorgeous figure like that; so open and compliant, waiting for Severus’ cock. Even if it was just the potion—and of course it was, because Black would never do this willingly—it was a glorious feeling Severus would never forget. For the rest of his life.
To see Sirius Black all poised and ready to be fucked.
And truthfully, he had as good as asked for it.
Severus stroked his dick again, and it took only seconds to bring to full hardness once again. He panted as he lined himself up, taking Black’s hips in his hands to position him. He hadn’t realized Black’s skin would be so smooth or so warm. He also didn’t realize his hands would overlap Black’s in this way, like they were holding him open together. Black spread his legs a bit more and Severus settled in properly, and then he canted his hips.
Breaching Black’s arse for the first time was like nothing he’d ever felt. Severus closed his eyes and pushed his cock into that tiny hole, which despite the loosening was nowhere near slick enough. The feel and the pressure was enough to make his knees buckle, but he kept his ground. Eventually, he managed to develop a rhythm. Back and forth, small thrusts, just enough stroke his cock deliciously.
He realized he was grunting, soft little wisps of noise escaping his throat. He realized Black was grunting. As he fucked him faster, there was the slap of his hips against Black’s arse and the smacking sound of Black’s cock against his abdomen. Severus pulled his hips into him, so hard that Black brought his hands back to leaning on his knees for support. But it wasn’t enough.
Severus pulled out and pushed Black forward. He took the cue and got on his hands and knees. Much better. It would be rough for Black on the stone floor, but Severus could be arsed about that. He quickly repositioned himself. His head fell back and his jaw dropped in that glorious slide back in. Even a scratchy moan escaped his throat.
Severus fucked Black until Black fell to his elbows, taking every thrust. He even slapped Black’s arse a couple of times for good measure, and wasn’t that just a thrill? His balls started to draw up, and he knew he was close. It took all of three more, deep thrusts to bring Severus over the edge. As his orgasm overtook him, he rutted haphazardly into Black’s arse, no longer caring about any sort of rhythm. He just needed to fuck, to keep fucking until the wave of it passed. Black gasped and moaned, and Severus felt the moment had come too.
Within a minute of catching his breath, cold reality struck him. The hazy room became clear once more. He pulled out, wincing at the sensitivity in his now softening prick, and climbed off of Black’s naked body.
Black breathed hard, dropping his head between his arms.
The potion should have worn off by now.
As he tucked himself back into his trousers, panic started to creep its way into Severus’ mind, and he considered that this was the perfect moment to cast Obliviate. Black wouldn’t see it coming, wouldn’t even notice. Then he could leave Black in here to wonder why he was alone in a room naked, run back down to the dungeons, and pretend none of this had ever happened.
Except, of course, he could never forget it now.
He had fucked Sirius Black.
That would be a fact, forever.
He tried looking for his wand but that invisible wall came back and seemed to block his way at every turn. No matter where he looked, he could see his wand nowhere; likely it had rolled away into the darkness. The wall closed in on him whenever he thought about getting up to go in search of it.
Black was picking up his clothes. He already had his pants back on. His knees were raw, freshly scraped up.
Severus battled with his feelings for so long, when he next glanced up, Black was fully dressed.
Black’s eyes kept darting in his direction, but Severus didn’t want to look at him. If he didn’t Obliviate him, he would have the shitstorm of all shitstorms to face tomorrow, and panic roared in his chest once again at the thought. Why couldn’t he make himself move to get his wand?
Black stopped at the door, turning only his head to not-quite-look-back at him. “Snape?” Severus looked up at him then, and he realized with a pang of torturous pain that Black was gorgeous. “You do realize that I share a room with James, don’t you?”
An image of James Potter sound asleep in a bed flashed in Severus’ mind.
“I would have known if the letter had been from him, you daft shit.”
Severus thought he noticed him smirk as he stepped through the door.