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There are moments in a human’s life where one can feel the shift in the atmosphere; the way the world just tilted on its axis, never to go back to normal again. And when magic is involved — dark magic — that life-changing alteration can really hold the power of a thousand full moons. Miya Atsumu will never call that night a mistake. Drawing that kind of power was crucial at such a critical time. However, his lust for strength will definitely take a toll on his mind and body for the rest of his life. A price Atsumu will be reminded of every time his eyes fall on the mark he wears on the back of his hand. Every morning when he has to conceal it.
Summoning dark forces isn’t a simple task. It also is a very illegal one. Only the best amongst the best wizards can pull it off without being detected. It takes several stages just to learn the proper rituals, even more to make preparations. It doesn’t even happen all at once. That night, when Atsumu sees the form take shape in the middle of his pentacle for the third time, he knows he’s succeeded. He also knows there will be no coming back after he utters the next words:
“Ś̵̮̭̫̪͙͈̤̦̙͋͐̃ͅã̶̡̢͙̣̭̦͇̹̬̬̍̔̑͐͘̚k̷̮̂̐͂u̵̼͕̻̳̜̭̫̻̳̲̅̓͗͆̂͌͆̕s̴̛͖͆̂̍̑̈̈̒̒̈́á̸̗̱̞̳̣̫̣͉ͅ ̵̢̪̗͕̪̞̘͊̔Ǩ̴̡̥͍̤̪̤͓̫̟̏̄̌̈́͊͛͝i̶̧̢͙̻̰͖̰͚͆̂̇̇͆̀͋̈́̑ͅy̵̧͉͍̤̦͓͠o̴̮̎͐̈́̉̓̕ơ̶̫̦̤̓̈́͐̃̌̌̐͝m̸̧̛͓̺̣̩̠ȉ̶͙͊̒̾̓̆̇͗̌͛ King of the seventh circle.”
He learned the demon’s name during the second summon and the circle — the deepest one — he’s coming from, during the first one. Atsumu’s guts twist in anticipation. He’s seen him more or less clearly over the last two summons and he knows he’s not ready to see his full form. Atsumu knows it’s not just a question of magic. Demons — in the way they present to humans — have always designed and shaped themselves to be the incarnation of tentation.
The creature that appears in front of Atsumu is the perfect demonstration of that. Dark swirls of smoke dissipate in the middle of the cellar. The air around Atsumu gets colder despite the myriad of candles burning through their wicks. It’s only fair, a piece of hell itself is materializing in front of his very eyes. Atsumu won’t regret it, but he knows nothing prepared him for that quite enough.
He braces himself as the figure unfolds, towering over Atsumu effortlessly. He is at least 3 feet taller than Atsumu, not counting the magnificent horns that protrude and curl back around each side of his beautiful face. The base is the same abyssal-deep black as the demon’s scleras, forearms and hands. It brings out the green of his iris, his talons and the tip of his horns even more. Atsumu swallows the lump in his throat as the demon blinks slowly. Two slits under his regular eyes revealing a second pair of eyes of the same emerald. His mouth reveals a set of fangs when he snarls before his lips twist into a smirk. The slits close back, but Atsumu remains restless. He should be repulsed by the demon’s appearance, not the opposite. His eyes should certainly not drop down to the creature’s midsection.
Demons know of the concept of shame; only to use it against human beings. Modesty is not in their book, either. He remains bare and proud, in front of the mortal who just cast him into this summoning circle.
Atsumu has never seen something like this. He should look away but his eyes are glued to it. So much so that when the demon speaks, it takes Atsumu a second too much to look up into his unsettling eyes.
“You are filthy, human.”
Here's an allegation Atsumu will have a hard time fighting, when he was just thinking that the cock hanging heavy between the demon's legs matches his horns. Its base is littered with the same asperities. Although if Atsumu was to reach and touch them, he bets it would be soft down there, while the horns look rough and harder than steel.
“That’s not a way to greet yer master,” Atsumu says, willing his voice to stay even as he looks straight into those soul-devouring eyes.
The demon scoffs, crossing his arms over his chest while he bends over to lean toward Atsumu. “As you see me, I’m nothing but free. And I reckon you can see me very well, human.”
Atsumu can see him very well, indeed. That powerful entity is already hitting a nerve. Maybe Atsumu feels already drunk on the power that’s within his reach, because his mouth turns into a sneer. He should know better than to be cocky in front of a demon of the seventh circle. But Atsumu isn’t actually wrong. There are only two possible outcomes tonight. Either that demon will go back to where he came from, or they’ll share a bond for life at Atsumu’s command. Blood will seal it.
“And what’s that supposed to mean? I should be ashamed? I’m not the one trapped and naked as the day I was born, demon.”
“Ashamed is not a word I’d use for the likes of you,” the demon says.
“What word would ya use, then? Choose carefully, I might not be as lenient as ya imagine once yer mine.” Atsumu’s bravado is loud enough to cover his deafening heartbeat for any other human, but for a supernatural creature?
“Ah. Usually, your kind inspires boredom to me, but hearing you claim you will own me while your heart wriggles like a desperate bird in its cage truly is amusing.”
Atsumu braces himself. “Ya’d call me stupid rather than brave?”
“Maybe you’re a bit of both. Although you cannot be that much of a simpleton, if you were able to summon me thrice, and all by yourself. You must know the rules, after all.”
“By heart,” Atsumu answers, eyes falling to the demon’s chest where what should be beating is long dead.
“Then will you give me your blood and break me free of that monotony of mine? I shall be yours for as long as your flimsy life goes by, until one day, your soul becomes mine.”
The demon opens his arms as he speaks, as if to welcome Atsumu. As the ritual goes, Atsumu stated his motives for invoking a demon on the first night. If Kiyoomi — a name Atsumu still can’t imagine pronouncing out of the pentacle — is there again tonight, it’s because he agrees with said motives. It’s not a surprise. Atsumu knows his charms aren’t all there is to it. In fact, despite their banter, he knows a mere mortal’s charms weigh nothing at all in this bargain. He seeks the destruction of his enemies: this is the promise of a feast for a soul-craving demon. What he must be looking for.
Atsumu could still turn back, but he won’t. This discussion came on the table too many times with his loved ones. He can’t save them from the world they live in without power. There’s no other way. So Atsumu brandishes the ritual blade he’s holding, then he steps into the first circle of the pentacle. Seven of them separate him from the center.
Atsumu waits to be in the third one to press the knife into his left palm, and the fifth to reopen his hand with a wince. The sharp pain shoots through his entire arm but Atsumu ignores it as best as he can, stepping into the sixth circle.
The tip of a dark green tongue appears between the demon’s lips before he licks them, eyes flashing bright. Atsumu extends a hand over the last line, and by this last and simple act, binds and seals their souls for the rest of eternity.
The first droplet of blood barely has the time to hit the ground that the demon pounces on Atsumu. Several candles go out before his body can hit the stone floor. A turmoil of emotions goes through Atsumu in that short span of time. Trepidation, dread maybe? But fear isn’t there. The bond is unbreakable and with it, Atsumu is safe from this demon’s claws for the rest of his life. He still hears himself shout: “What the hell are ya doing?”
And his stomach does drop in his belly when Kiyoomi rams him into the ground, expression tainted by pure lust and hunger. “Hell can’t help you when you invite it into your home, and I shall take you on this altar of sins. A mere consolation for the many times you and your boundless greed will take me for granted.“
The word ‘God’ stays stuck in Atsumu’s throat, burning. He’s read about this – rare occurrences at least.
“I can’t hurt you and I shall not.” Kiyoomi’s words make a real impression on Atsumu, and not just because the demon whispers them against his face. The only way for Atsumu to get hurt in the process of what’s impending is for him to resist. And he doesn’t want to. Deep down, he knows why he dismissed the information. Why Atsumu didn’t linger on those ancient scriptures that talked about bonds sealed in blood and passion. It’s because it didn’t scare or repulse him back then. It still doesn’t. In fact…
Kiyoomi’s arrogance shows in the way he smirks at Atsumu. The bond they share doesn’t lie. The demon is now privy to Atsumu’s most intimate thoughts and desires. “So you shall not be hurt,” he repeats, and warmth blooms in Atsumu’s guts. Kiyoomi read him like an open book.
“Wa—Wait!” Atsumu yelps when Kiyoomi goes from standing on all four over him to kneeling over his thighs, talons digging in the leather of Atsumu’s pants.
He looks so big and his shadow — roughly cut where it’s cast on the ceiling by the candlelight — is one of a monster.
The demon’s hands stop moving just as his talons brush the skin of Atsumu’s lower abdomen. He looks at Atsumu whose gaze goes past him and straight at the menacing silhouette on the ceiling. “Yer… Yer—I’m just…”
Kiyoomi’s derogatory scoff makes Atsumu glare at him. Not that there’s any spooking the Boogeyman himself… But he does remove his hands and holds them up for Atsumu to see as he sits back on his ankles. Then, in a matter of seconds, Atsumu sees the demon’s body shrink to a more decent size, the huge talons at the end of his fingers retracting into claws. Kiyoomi is still way taller than Atsumu, especially when Atsumu is lying on the ground at his mercy, but Kiyoomi has at least turned into something manageable for him to handle. Although not in his wildest dreams would Atsumu have imagined lying there to be taken by someone so massive.
“Your kind loves to play with fire. Are you now just realizing what me being yours implied?” Kiyoomi asks as his claws work on the leather of Atsumu’s pants.
Atsumu can feel the material slip over his thighs, exposing his skin to the cellar’s cold air. A shiver runs down Atsumu’s spine. “I know what I’m doin’.” He doesn’t shake when he says this, and Atsumu is even more adamant when he adds: “I know what I want.”
“A good thing your wish is my command,” Kiyoomi growls, hands grabbing Atsumu’s shirt next. It rips under his swift and forceful pull. Atsumu’s breath catches in his throat. The next second, he right out chokes when Kiyoomi grabs his thighs and yanks him upward.
Atsumu’s shoulders are pressed into the stone floor, his lower half completely exposed by the demon holding his legs apart in the air. Atsumu is then bent in half, legs pressed back against his chest to expose his ass. Atsumu could die — except he won’t. He can see the demon’s face between his legs where he licks his lips like a predator about to devour its prey. Kiyoomi is kneeling on the floor, leaning over Atsumu’s body folded in half for him to eat up. Atsumu can’t close his eyes despite the embarrassment — despite how vulnerable he feels. And when Kiyoomi’s tongue peeks out, Atsumu finds himself unable to look away, anyway — entranced by the sight.
It’s a ridiculously long tongue. It’s the same color as the tip of his horns and cock. Not quite charcoal black, there’s a hint of deep forest green and—oh fuck. It’s like a snake’s. Atsumu’s eyes go wide looking at the forked tongue that gets closer and closer to his skin. Until they suddenly shut tight. Atsumu throws his head back against the hard ground beneath him when the tongue swipes over his hole. He contains a throaty moan with difficulty but can’t refrain from squirming as the tongue probs at his rim with eager flicks. Kiyoomi laps over Atsumu’s tight asshole, then all the way to his taint… Then the demon gets even greedier and Atsumu feels his sinful, inhuman tongue curl around his balls and he’s gone. He lets go of a short but wanton shout from the pleasure building into his core and it’s probably all the demon wanted to hear before swallowing Atsumu whole.
Atsumu never lost his mind to sex prior to this day. But he’s never had an oversized tongue down his asshole, fucking him and splitting him open better than any cock did before. The odd feeling disappears pretty fast because the stretch is nothing but delicious. Kiyoomi’s tongue is strong and demanding but it’s soft enough not to hurt Atsumu’s walls. Maybe there’s something demonic in his saliva, maybe not, but the glide it provides is out of this world. Atsumu can only writhe on the floor, moaning in delight. Kiyoomi thrusts his tongue in and out, twisting it so it licks at Atsumu’s every and most intimate corners. He sucks on his twitching hole, making Atsumu keen and arche off the floor even more.
Somewhere distant at the back of Atsumu’s mind, he registers the strain on his shoulders and the pain blooming in the back of his skull but it gets numbed by the blinding pleasure. Kiyoomi’s claws dig in the flesh at the back of Atsumu’s thighs as he presses down on them — folding Atsumu further in half. His own dick dangles above a few inches away from his face now. The sight of it getting harder and harder makes Atsumu as dizzy as having the demon work his tongue into him.
Kiyoomi grins when Atsumu whimpers, baring his fangs that graze over the sensitive skin around his hole. Maybe Atsumu will die tonight, but it’s absolutely on him. Kiyoomi can claim his soul at this point. He’d be allowed, it’d be fair game.
Then, as promptly as pleasure assaulted Atsumu, Kiyoomi’s tongue disappears and Atsumu’s abused hole is left blinking pathetically, the freezing air hitting him without mercy. It makes his cock throb. Atsumu opens his eyes — just realizing they were closed. He has to blink some tears away so he can look up at Kiyoomi through his trembling legs because Atsumu’s vision is blurry. Kiyoomi is staring down at Atsumu with a feral smirk. He’s not human in more than one way. Atsumu might have gained immense power binding himself to this creature, but he’s absolutely powerless under him and he wants to be.
“We usually feast on you mortals’ anger and sadness, but I’m going to have the time of your entire life eating away at your lust and greed,” Kiyoomi purrs. His dangerous nails rake over the back of Atsumu’s thighs as his hands draw near to his ass. Then they knead his cheeks, parting them to expose Atsumu even more. He squeezes his eyes shut again, too self-aware. “Don’t look away, Atsumu. See how much you want it.”
Kiyoomi parts Atsumu’s legs even more, bending over his body until… “Fuck!” Atsumu shouts again and the rest of a string of curses stays stuck in his throat.
Kiyoomi’s tongue is back to working on him — but this time, it’s curling around Atsumu’s hard cock. It swirls all around him, up and down, covering almost each centimeter of skin — and it’s not like Atsumu has anything to be ashamed of in this department. It doesn’t matter; Kiyoomi is a demon and his body has its own rules. Atsumu never experienced that before. His cock being swallowed by a demon’s tongue. It’s hot — burning even —, it sends his mind reeling. Atsumu’s sanity can’t hold up against Kiyoomi’s assaults, neither can his body.
Kiyoomi doesn’t even need to suck him off. His indecent tongue works around his dick in a tantalizing way. It squeezes the shaft, toys with the head, probs at his slit… It’s everywhere. Atsumu’s nails dig into the ground under him, knuckles turning white. It’s too much. Then Kiyoomi closes his lips around the tip of his cock. The rest of his tongue curls around its length and Atsumu’s hands fly up to grab Kiyoomi’s horns as his entire body goes taunt. He’s never come this hard in his entire life. Kiyoomi’s spit isn’t demonic, his entire being is. It has to be the sole reason why Atsumu is living an out-of-this-world experience in this forsaken cellar.
He doesn’t even register the ache flaring through his palms as he rides his orgasm on the demon’s tongue, clutching his horns like a life-line. The hard dents dig into Atsumu’s skin. It’s rough to the touch. The mix of pain and pleasure blends into the most perfect bliss.
Atsumu lets go of the horns only after his whole body relaxes. He can feel his consciousness slip away from him for a millisecond as he goes pliant. Kiyoomi is still holding him — which is the only reason why Atsumu doesn’t slump on the ground. That kind of satiety can’t compare to anything Atsumu remembers. The only problem is that the feeling won’t go away. Kiyoomi’s tongue is still wrapped around Atsumu’s cock, undulating in slow, firm motions. It licks him clean, laps at every last drop of come Atsumu spent. It squeezes his overstimulated cock, relentless.
It’s not long before Atsumu starts spasming — shaking — trying to writhe away from the sensation. The onslaught of sensations. “I—I’m…” he can’t even speak properly yet, but surely the demon will get what Atsumu means. Sure enough, Kiyoomi does. His tongue disappears, not without torturing Atsumu one last time by curling around him from base to tip. Then… Peace. Atsumu’s eyes flutter shut. Whatever the hell he signed up for, for the rest of eternity, is something he might be happy with if—
“What the fuck!” Atsumu yelps as his full body is suddenly slammed against the floor.
Kiyoomi manhandles him like Atsumu is but a mere ragdoll. And if he thought he was folded like some origami before, he was wrong. Atsumu’s shoulders get some reprieve as his back is also pushed onto the ground, but it’s for the demon to better bend him in half. His body might snap. His thighs burn when Atsumu’s legs are pressed against his own chest. He has no way to defend himself. Kiyoomi is strong and Atsumu is still in fucking orbit. His protest isn’t even real, it’s not even stuck at the back of his throat. Atsumu lets it happen, despite the way his insides churn. The thrill of excitation kills the buzzing dread that makes his fingertips prickle.
Still… “Oh no, no, no…” he whispers as the demon mounts him with a groan. Atsumu finally understands what’s about to happen when his oversensitive cock is trapped between his own abs and thighs. The demon’s weight makes it impossible for him to run away from the dizzying feeling.
“You don’t mean the words you speak,” Kiyoomi growls into the crook of Atsumu’s neck as he bends over him, covering Atsumu’s body with his own.
Atsumu would jolt if he wasn’t caged and pinned down but he can’t get away, even when he feels something heavy and hot drag against his ass.
“Wait—” Kiyoomi is right, Atsumu wants it. But his body isn’t ready. His entire skin is on fire, his spent and abused cock is throbbing. His heart is hammering into his chest and he can barely breath in the position he’s kept in. He’s not even sure he can take this thing. A demon’s magical tongue is one thing, but his massive cock? It’s already growing thicker and harder against his skin, nudging Atsumu’s crack and spreading him apart.
Atsumu swallows the little saliva left in his dry mouth. The odd thing is that Kiyoomi’s cock rubs against him without any friction, even with the little protuberances that circle around a solid part of his length… It doesn’t hurt. It doesn’t even bother Atsumu. It’s downright arousing despite how nervous and overstimulated he feels.
“How about the trust you have to place in me for as long as our bond lives on?” Kiyoomi grins, hands splayed on each side of Atsumu’s face as he props himself up over him.
He rolls his hips back and forth, his filling cock dragging over Atsumu’s sensitive hole. It awakens Atsumu’s need to be filled up again. It makes Atsumu yearn for it. That demon and his forked tongue were right. He wasn’t ready for what he got himself into. Nor for what’s about to get into him — inside Atsumu, to touch his most private parts.
“I trust myself not to have missed when I made you mine, demon,” Atsumu says, gathering all the bravado left in him. “Kiyoomi. I’m gonna play with that name as much as you intend to play with me.”
“If it pleases my master,” Kiyoomi answers, and everything from his sly grin to his incandescent gaze is predatory.
It’s a bit ironic that Atsumu is thinking about how he can count his blessings when a literal lord of Hell chose to take him. But it’s not like he has any time to linger on that. His wits are the last thing he can show for, and Kiyoomi takes that away from him when he shoves himself into him without any other warning.
White dots dance in front of his eyes as Atsumu is impaled on Kiyoomi’s huge cock. The impossible stretch steals his breath away, robs him of his sanity. Atsumu might be the master of this demon, but he’s sure turning into a slave to lust for him.
However, pain never comes. Atsumu knows he’s past his limits in absolutely all the ways he could think of if his mind hadn’t gone blank. Yet all he can feel is pure ecstasy. It could be magic, it could be anything else… Atsumu lets Kiyoomi possess him entirely. And Kiyoomi takes him. With deep and powerful thrusts. He fucks Atsumu through the floor in the middle of this pentacle as if trying to make a point. Their bond is unbreakable. Stronger than any magic Atsumu will ever cast again.
It’s so overwhelming, Atsumu feels something hot run down his temple, all the way to his hair, and he realizes it’s tears. But when he tries to wipe them away and hide his face, a powerful hand grabs both Atsumu’s wrists and pins them above his head. Kiyoomi’s emerald eyes are glistening in the dark of his sclera. The green of his iris is vibrant, like a beacon into the night. Atsumu gets lost in them. He whimpers when Kiyoomi leans into him even more to press his lips against Atsumu’s mouth. His cock is hard again — it’s all too soon. Atsumu can’t speak, though. Because here comes this demonic tongue again, breaching the seal of Atsumu’s lips to lick into every corner of his mouth. His tongue isn’t as long as before, but it’s still enough to silence Atsumu. To thoroughly take him like the cock that spears Atsumu.
“Please,” Atsumu begs the second he has the chance. He doesn’t even know what he’s pleading for. Release? Mercy? Less? More?
Kiyoomi’s grasp on Atsumu’s wrist tightens for a second before he releases him to grip his jaw instead. His claws are dangerously close to Atsumu’s eye but it doesn’t scare him. He wants these hands to hold him for the rest of eternity. Kiyoomi’s pace slows down until he’s only grinding into Atsumu, balls deep. Atsumu is filled to the brim.
“You could ask for anything, and then some more, but all you want right now is to submit to your pulsions and desire. Do you even realize your power? Do you even know who’s holding you right now?” Kiyoomi speaks in an ancient language — long forgotten. Yet Atsumu understands every word. And as the demon utters them, Atsumu feels the back of his left hand burn.
“I do,” Atsumu groans, voice broken.
“Then say my name. Seal our bond, Miya Atsumu.”
Kiyoomi slams into Atsumu, burying himself to the hilt. The pain shooting through Atsumu’s hand at this instant is excruciating. But as intense as it feels, it can’t rival the devouring fire consuming him whole and dragging Atsumu deep into a sea of pleasure.
When Atsumu calls for the demon, he doesn’t recognize his own voice. It’s ancient too. The same cavernous otherworldly tune. It comes naturally to him. And it makes Kiyoomi growl above him, his eyes glistening in the darkness. Atsumu doesn’t remember much after that. He remembers Kiyoomi going feral. He remembers being fucked within an inch of his life until he doesn’t. Only the pain on the back of his hand keeps him grounded enough to not lose consciousness entirely. The rest is history.
When Atsumu comes to himself, he’s lying on the cold, hard stone, fully nude. His entire body is sore, his head hurts. And when he brings his left hand to his face to wipe away the thin film of sweat covering it, Atsumu’s eyes go wide. Carved into his skin: delicate lines, already healed. The mark he’ll have to cover for the rest of his life. The proof that this wasn’t some kind of weird fantasy. As if he needs any…
Atsumu can feel him. Looming in the dark, in a corner of the room. The candles all went out but his presence is absolute. Atsumu will never spend another day, another second of his life without this presence to bear.
Sakusa Kiyoomi, king of the seventh circle.
Atsumu’s servant for life.
“So, what will it be? Should I call you master?” he asks Atsumu as he steps closer, now that Atsumu is fully awake.
For a moment, the wizard ponders. Names have meaning. They hold power, secrets, a sense of belonging. A mutual bond. Trust. It’s folly to associate these words to a demon. But Atsumu has done crazier things — his body still bears the marks of his most recent madness. He might not be able to sit without wincing, but Atsumu isn’t scared. Not when he reaches out to take the hand the demon extends to help him to his feet. Not when Atsumu touches the twin mark carved into the skin over the demon’s lifeless heart. He’s not afraid when he looks into his soul-sucking eyes. Fear is not something he will ever feel again.
“Call me Atsumu, for I shall call you Kiyoomi. Call me yours, because I’ll call you mine.”