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For all the five hundred years he had lived, Kokushibo, of all the things he witnessed and accommodated to, had never expected to end up where he currently did. Laying with his back pressed to the floor, hair a mess, wrists pinned separately beside his head. And there he was, his master and lord, looking into his eyes, searching and reading him. The past slayer had not expected things to escalate to such level. Maybe it was just all but an impulse of the moment. Or perhaps it was something that has been building in his master (or both of them) for a very long time and he simply didn't realised it. But before he could utter any words to come, he felt a pair of lips clashing against his. Not gentle, not soft, but rather all rushed and greedy, as if finally tasting some kind of forbidden fruit his lord had long denied himself and now was taking his claim. Kokushibo’s eyes widened yet he was in no place to deny his lord, not when someone like Kibutsuji Muzan was suggesting it of all people and demons walking and living.
And so he responded, kissing back, lips moving against lips, all focused and needy, saliva mixing together. Kokushibo felt the demon progenitor bit into his lips, fangs drawing scars that made the blood running gently, though it healed in no time. He parted his lips and almost immediately felt the other man’s tongue in his mouth. Both tongues danced and twirled around each other, the men receiving pleasure in equal measures. And as it all was happening, Kokushibo could feel a tug at the opening of his kimono. The hand of his master, usually so brutal and fast to end lives, so strong and powerful, felt almost like a caress compared to how brutally it had killed both men and demon. Soon enough their lips parted, leaving a string of saliva connecting them, their breaths mingling together, warm. But Muzan left no time for his upper one to fully enjoy the moment as he swiftly turned to assault Kokushibo’s neck, placing hot, open mouthed kisses, fangs tugging onto the sensitive skin there. Instinctively Kokushibo titled his head, hands gripping the demon progenitor’s shoulder blades, biting back a moan.
It felt definitely different. Not in a bad way per se. Far from it in fact, but the upper moon would be lying if he claimed that it wasn’t surprising. Back when he were still but a mere human, weak and helpless, it was his duty to produce heirs, to make sure the family name would be to stand still. And yet his marriage was a loveless one with no passion whatsoever, only an alliance formed on duty.
Though before he could dig more into it, his mind quickly came back to the reality, to the current moment.
Muzan’s fangs had cut his skin deep in several places on his neck to leave trails of blood flowing down the delicate skin, lips already moved to his collar bones. That was until the demon king halted for a moment, looking up at his creation.
”Must you really keep that head of yours so busy with such foolishness? You don’t want to dwell too much into the past now, do you?" he asked, a hint of irritation clear in his voice. Kokushibo blinked in surprise, a shameful expression appearing on his face.
"No, of course not my lord." How silly it was of him to forget himself in such a moment, analysing the past instead of sinking into the pleasure his lord was giving him. But before he could think more a whimper escaped his lips as he felt sharp teeth harshly biting into his skin right where neck met shoulder. The lord’s hands started roaming and touching his body more greedily, gripping and caressing every curve and dip as the assault on his neck has continued. Soon enough the first upper moon felt his chest being exposed to the cold air, the demon king planting wet, slippery kisses to his chest and stomach, all the way down to his waistband. Kokushibo could feel the hardness growing in his pants, slowly turning impatient. Muzan have well realised that he was just as bothered as he was, yet decided to tease him at first, to make him wait, earn it, make him go crazy and impatient and all the things that would turn him mad.
His fangs tugged on the white sash that held Kokushibo’s trousers, teasing, grabbing but not yet untying it.
Kokushibo’s breath hitched, his hardness feeling more bothersome with each passing moment. He buckled his hips, trying to get even some relief. The demon progenitor looked at him, holding the eye contact just before he started kissing him breathlessly all over again. Taking the advantage of the situation, Kokushibo started unbuttoning his lord’s vest, the cloth hanging on the man’s figure now. The same thing happened with the white button shirt underneath. Their kiss in the meantime had turned messy, blood mixed with saliva, both moaning into each other’s lips. Muzan broke the kiss, taking off his vest and the crisp white shirt, his muscles visible. He positioned himself between Kokushibo’s legs, looking him up and down before his hands rested on the man’s hips.
"We just started and you’re already bothered?" A teasing smile formed on his face, thumbs brushing the white belt. The upper one felt his cheeks heating up, eyes wandering everywhere but on Muzan, frustrated.
"Huh." Muzan looked at Kokushibo, analysing his movements and behaviour for a good few moments.
"There’s no need to keep it to yourself, Kokushibo." He whispered, leaning closer. It was all teasing and frustrating touches, no real action, no more movements. Yet throughout it all Kokushibo had mostly kept quiet as he wasn’t the one to speak much, though he had to admit that such behaviour was making him all impatient and he was almost sure it was all on purpose. Though the moment he felt cold air hitting his most intimate areas in the least expected moment he couldn’t help but feel his cheeks heat up at being exposed just like that. It has been such a long time since the last he had gotten bed by someone and suddenly he was experiencing it all over again and by no one else than Kibutsuji himself. Hundreds of years ago he probably would’ve told himself how foolish and unrealistic this scenario seemed to be but currently it was so very real and true. Muzan toyed with him for a few more moments, caressing his thighs from inside, thumbs brushing over the soft skin there. And all while looking at the other demon in the eye, daring him, challenging him to do something - observing. Kibutsuji was a man that wanted to know why something worked they way it did, why things behaved that way and not the other. It seemed, that for tonight he had found a subject he wanted to understand, laying all nude under him. A pleasant sign indeed.
Kokushibo buckled his hips once more, desperate and more impatient for some action. The demon king was a man who played by his own rules and it showed. But oh, how Kokushibo hated it now, how it bothered him currently. Yet forcing Muzan into something was like chasing a ghost - impossible to achieve. But just as he was about to say something he would most likely regret, he felt something. What a sly bastard. The demon progenitor had already entered him while he was deep into his thoughts. The upper one couldn’t help but let out a moan as he felt his lord’s member inside him. His hands instinctively ran to the demon king’s shoulder blades, nails scratching and digging, trying to steady himself. In return Kibutsuji moved their hips together, thrusting inside him. Their movements were slow at first, Kokushibo adjusting to the sensation, panting quietly into the other man’s shoulder, trying to quiet down his noises. With each passing moment Muzan started moving faster and faster, greedily, as a sly, satisfied smile formed on his lips. Their breathing became heavier, sweat forming on both bodies. No one spoke much. Not because it was awkward but because it wasn’t necessary, nor did they found any reason to talk about anything. Then Muzan thrusted deep and hard, making Kokushibo yelp as he felt his thoughts getting foggy and unfocused little by little. His thighs started shaking ever so slowly as the demon progenitor started moving only faster and harsher, both panting.
When they both came they were breathless, gasping for air, chests rising and falling. Muzan’s member had left Kokushibo not that long ago and the upper demon felt this empty sensation at first, too tired to think about what had happened just now, propped onto his elbows. Though as his mind became more clear he felt his face heating up as his eyes locked with the demon king’s. Muzan looked down at him, already knowing all the things that were going on in his head and just smiled. That cunning smile that hinted at hunger that was still there and kissed Kokushibo, pinning him to the surface once again, pinning his wrists.