Work Text:
"Nakime. Would you please transport Kokushibo to my study within the next hour or so? He should be back from the assignment I sent him months ago at some point today."
A small voice could be heard throughout the castle: "He returned earlier this morning; would you like to see him now, sir?"
Muzan raked a hand through his raven hair and sighed. He was hoping to have a little more time, but it honestly didn't matter. "I see. Go ahead and bring him to me."
The strumming of a biwa echoed throughout the walls of the never-ending fortress, and Kokushibo appeared behind Muzan.
He looked perfect as usual. His blood-red hair was in a practiced ponytail, and his dark eyes were outlined by both his pale skin and his gentle eyelashes. Everything about the tall demon was perfect—exquisite, even. He was made by the hand of the demon king, after all, but sometimes Muzan was impressed by his own abilities, creating something so perfect that even he would be entranced by the creature.
He didn't even realize he had been staring until Kokushibo finally spoke, "Muzan Sama? Can I assume you wanted to know how the assignment went? It's been quite some time since I've gone on such a mission, but it was successful."
Muzan cleared his throat. "Of course. Tell me."
He paid attention at first, listening to how Kokushibo was able to track down the first sun-breather family. He mentioned them having a house-sitter who was cooperative, and their oldest child being in training with the slayer corps.
Then he was distracted again.
His focus shifted to how Kokushibo's lips moved. They were vaguely shiny, and every time they moved, he could see fangs poking out. His teeth were in perfect condition, well suited for tearing hearty human flesh from bone. His gaze moved further down still, watching as the taller demon's voice box moved in his throat. It pushed out his skin, and Muzan couldn't help but want to lunge forward and sink his teeth in. He knew that it would taste divine: the blood would slip down his throat, and the soft skin would be a blessing against his lips.
The way he imagined his subordinate's skin would feel almost godly against his, it was holy. If he were a mere mortal, he would probably be very willing to kneel at any alter if it meant being able to experience that feeling.
His thoughts were again interrupted by the subject of said thoughts, "Muzan Sama? Are you quite alright? I apologize for prodding or stepping out of line, but you seem distracted."
Muzan sighed, ...Fuck it.
"Kokushibo, I have a question for you. Would you like to take a guess about what it was like to not have you around for almost a year?"
Kokushibo looked confused, those hypnotizing eyes blinking uncertainly. "I'm not sure I understand the question. But if I had to guess, I would assume it was unorganized. I tend to keep all the castle demons in check with Nakime while you attend to other business. Not by any fault of your own of course, you are the Demon Progenitor, of course you would be busy quite a lot.”
Muzan laughed. "You are correct, but that isn't what I mean. I meant for me; how do you think I felt?"
Once again, the other demon looked confused. "I do apologize, but I am unsure what you are implying.”
"As to be expected, please come forward."
The Upper Moon took several steps forward, so he was only a couple feet from the Progenitor of Demons, only to be directed closer by the motion of an index finger. By the time he was directed to stop, he was so close to the ravenette that he could feel a cool breath on his neck.
A hand reached up, lightly grabbing Kokushibo's jaw and pulling him to be at face level with Muzan. "It was definitely a new feeling. I almost wanted to see you... no, it wasn't a want, more a need. I needed to see you."
The way Kokushibo's eyelashes fluttered in utter disbelief was absolutely delectable.
"The longer you were gone, the more I thought of only you. Until you consumed my every thought, in more ways than one. Whenever I slept next to the human wives I keep, my dreams were only of you, and what if it was you in bed next to me?" He paused before continuing, leaning in so his lips were pressed to Kokushibo's ear. "There were several times where I wanted to go out and finish your mission myself so that I could lay my eyes on you; maybe I would stop being plagued by these thoughts. I was hooked on the mere thought of you—on the thought of what you might feel like under my hands."
"Muzan Sama, how could you… I mean, how could I-"
All of a sudden, Kokushibo and Muzan had flipped places, with Kokushibo's back crashing into the wooden desk and probably leaving a dent. He didn't have time to process before a pair of hungry lips were pressed against his own.
Muzan had been right.
Kokushibo's lips were unbelievably soft. It felt like he was kissing an angel instead of a demon.
He groaned into it, pressing himself further and resting a hand on the man's chest. He pushed purple fabric away with his fingers, itching to feel bare skin. He scraped his nails over the plump flesh, drawing circles around Kokushibo's pectorals.
He parted from the man below him, looking down with a grin at the surprised and almost dazed expression on the face of the esteemed Upper Moon One. His most prized demon was left completely powerless by his advances.
"Fuck, you really are divine, just as I imagined. Sometimes I wonder how I created such a perfect being, maybe even more so than myself."
He caressed the younger demon's jaw, leaning down again to kiss any available patch of skin he could get his hands on. He covered his jaw, traveling down his neck and right to the junction where the neck met defined shoulder muscles. Muzan couldn't help himself as he sunk his teeth in, drawing a low moan from both of them.
It was the best thing he had ever tasted. Better than the finest Marechi, it might even pass for the best wine in the palace of G-d.
Crimson blood traveled down his throat and over his lips, dripping down his chin messily. He dug further, sinking his teeth so far down that he started to scrape at bone. It drew a noise like music from the man below him—a grunt that turned into an almost whimper.
It made Muzan chuckle, sucking at the wound and digging his tongue into the skin. The more he drank, the more he felt light-headed, like he was actually drunk off of Kokushibo.
When he finally let go, he licked the blood from his lips and chin and watched as the wound healed instantly, replaced with more perfect skin.
"Michikatsu, you're absolutely delectable."
That drew a gasp from the demon. He hadn't heard that name in over three centuries. It was like Muzan had just said something forbidden, it felt so hot and overwhelmingly intimate.
"Muzan Sama, I don't understand how I could draw these feelings from you. How could-"
He was cut off when Muzan bit down again, but not in his neck. He let out a loud and desperate groan as Muzan sank his teeth harshly into his chest. He ripped out a piece of him and swallowed eagerly, impatient as ever to have that feeling of absolute, weakening goodness slide down his throat.
"Oh, my dearest. I don't understand what there is to not understand."
Kokushibo tried to catch his breath enough to respond, but his voice came out much more breathy and weak than intended. "You are... infatuated by me?”
"My dear Michikatsu, infatuation would insinuate that this is temporary, and I assure you it is not. As the Turkish would say, kara sveda. It's a term that represents passionate and binding love for another being. That, Is what I feel. And I am more certain of it than anything else in my life.”
He leaned in closer, his lips brushing with Kokushibo's. "If you don't understand that? Then my dear, I fear you never will."
This time it was Kokushibo who couldn't help himself; his body moved closer on its own, and his lips crashed into Muzan's. It was desperate in a way he didn't recognize; he practically whimpered when Muzan kissed back with just as much desperate fervor. He wouldn't have recognized it until now, but he was also in love. Kara svede. Forever bound.
He had yearned for something while he was away, and only now did he recognize what it was. He wanted to feel his own maker above him desperately; he wanted his maker to unmake him in ways that were so painful that they turned into white and fiery pleasure. He was fixated on the thoughts; he needed them to become reality.
They were both addicted to each other.
They were absolutely addicted to each other in ways that could only ever lead to ruin.
Kokushibo moaned loudly and desperately as Muzan left his lips, sliding lower and lower. A clawed hand wrapped itself around Kokushibo's thigh, squeezing and inching closer to where Kokushibo knew he desperately needed it.
He groaned when Muzan stopped, his eyes full of desperation as those beautiful red eyes of his god looked into his very soul.
"You look absolutely gorgeous, Michikatsu. I want to absolutely ravish you; tell me how you want me, and I'll give it to you—I'll give myself to you"
Kokushibo was breathless, but he wanted to listen and be good more than anything else. It was weak and pliant, in ways he used to find disgusting, but he couldn't care less at the moment. "I want; no, I need-"
A sickeningly annoying voice breached the pair's ears: "Muzan Sama!!"
"Are you fucking kidding me? That stupid ice brain is the bane of my existence sometimes." Muzan went from looking absolutely in love to looking like a tired babysitter.
He stood up quickly, allowing Kokushibo to sit up on his elbows. He straightened his hair and fixed his disheveled appearance with the near snap of his finger before turning back to face Kokushibo, "Don't start having fun without me, dearest."
Muzan moved closer quickly, leaving a chast kiss on Kokushibo's lips before he disappeared to go find out what Upper Moon Two needed from him.
The six-eyed demon only nodded, fighting to stay still and do exactly as his lord asked of him. He didn't want to ruin what he now realized he had been yearning for his whole existence. Ever since the moment he met his red eyed Aphrodite.