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His heat was coming in a couple of days, he could feel it creeping up on him, dragging him down with its enticing fingers, making him hasten in his quest to return to the rally point; to the Butterfly Mansion. One of the signs was difficulty sleeping and Zenitsu at this point was certainly suffering from that.
Chuntaro chirped sympathetically on his shoulder as Zenitsu quietly approached an inn etched with wisteria flowers. He’d be safe there, hopefully. And as night began to fall, his mind was made. Better off safely staying here than wandering across country for another day on the brink of his heat and utterly drained. Still, once day broke, he’d have to hightail it back and hope his companions were there to help him cope with his heat.
His hosts took excellent care of him while there and for the meantime, Zenitsu felt safe, although it was not to last.
Sleep took him easily, but as he faded, curled into his futon, he could almost swear that he heard someone or something sneaking around the inn. Fear grips his gut as he imagines it to be some kind of demon. But what were the odds of that? The inn was imparted with wisteria petals in its walls. It’d be far too much trouble for a demon to enter, assumedly.
Still, Zenitsu fell asleep clutching his sword and managed to get some sleep at the very least before he awakened hot and sticky, feeling an uncomfortable presence in the room with him. A demonic presence, that is.
Jolting awake, Zenitsu goes for his sword, only to find himself hastily pinned beneath a scorching hot body and his sword nowhere to be found.
It’s too late. The demon is far too strong for him to compete against, especially in this state. Dread filled him as the realization hit that he was either going to be violated or eaten, or hell, maybe both. And then, it spoke.
“Worthless omega,” it scoffed, his voice a husky snarl.
His stomach dropped. He knew that voice. Even in a scenario like this, his ears wouldn’t be deceived, especially when it said the same phrase he’d heard hundreds of times from his peer.
"Kaigaku?" He murmured. But it couldn't be, could it? Kaigaku wasn't a demon. He'd never become a demon! Not his Kaigaku!
"Shut up! You don't get to use that name," the creature wearing Kaigaku's face snarled, but Zenitsu knew it was him. The timbre and tone of his voice was spot-on. He'd know it anywhere with his acutely accurate hearing. And not only that, but the smell of alpha, Kaigaku's scent like a lonely forest amid a roaring storm, but among that, there was a bitter, foul scent of something cruel and evil mixed in, something that made Zenitsu's stomach churn. It was him alright. It was Kaigaku.
"Nii-san, what have you done?" Zenitsu asked, his voice low and strained now that everything had clicked into place.
"Don't call me that either! You're an idiot if you think I'd ever let a weakling like you call himself my brother! Now you're even more of an idiot," Kaigaku sneered, still hovering over the blond, holding his arms out over his head with one hand and with his other, callously pressing Zenitsu's face to the floor.
Zenitsu struggled against him, but with all the factors weighed against him -- his approaching heat sapping his strength and his opponent being an actual demon, not to mention his lack of upper body strength in the first place -- he was practically powerless. "What have you done? Why are you doing this? Why'd you let yourself get turned into a demon?!" He frantically inquired, squirming in his grasp, yelping once the demon tightened its powerful hold on his wrists.
"Didn't I tell you to shut up? Even now, you're not even worried about yourself or your needs. You're worried about me and it makes me sick!"
Of course he was worried about him! He's-! Well... Zenitsu's always cared about Kaigaku. It's what Gramps would have wanted and if Zenitsu didn't care for him, then who would?
"If you weren't so weak and pathetic, maybe you would have never ended up in this situation. But now? Now I'm going to put you out of your misery," the demon stated firmly, dangerously lowering his voice as a warm huffed grazed over Zenitsu's ear.
"W-What?!" Zenitsu squeaked, but rather than fight as he would have against any other opponent, he lay there, frozen. He glanced back, straining his eyes as they adjusted to the darkness, his heart pounding away in his chest as he attempted to see the alpha, but his limited field of vision caught only a glimpse of a pair of pale jade eyes that seemed to glower far to close to his face. Far too close to the sensitive scent gland that his hot breath ghosted over. Luckily, it was concealed by the jinbei he'd been given while resting here, but it was still a quickly growing concern of his.
The demon nuzzled against the clothed gland, mouthing over it, a fang catching on his sleepwear and grazing the skin beneath, sending anxious sparks through him all the way down to the tips of his toes. He may have also let out a little moan, receiving an equally receptive, low growl from the demon.
"Kaigaku..." Zenitsu breathed, "what are you doing to me?"
"I'm going to eat you all up, of course," he answered matter-of-factly, like it was the most obvious thing in the world. "I'm sure Kokushibo won't mind this side-stop if I bring him your head."
"Kokushibo?" Zenitsu repeated, positively baffled, but in the next moment, he found a surprised yelp drawn from him as Kaigaku ripped his fangs into the cloth and tore it away, exposing his bare neck and shoulder to the cool night air.
"Stop talking," Kaigaku growled, his voice muffled before dropping the damp fabric and mouthing at the vulnerable mating gland and the tiny cut he'd left there, running a wet stripe from Zenitsu's shoulder to his gland, sealing his lips over it and drinking in the blond's flavor.
Such lewdness had slick oozing out of him and made his small cock ache for attention. His body was going lax from the alpha's attention without any complaint to speak of but his head, despite his instincts crying for a viable alpha mate to breed him, he knew this was wrong. Maybe not wrong, but definitely dangerous. Kaigaku was a demon now and he was a human, and not only that but the alpha had admitted to wanting to kill him.
"Please..." he murmured. "Please don't do this." But his voice had no finality to it and as Kaigaku continued to lave his tongue over his mating gland and gave it a particularly hard suck, his pleas were put to rest with a pleased mewl. He was doomed.
Kaigaku rocked his hips against one of Zenitsu's thighs, a groan rumbling and resounding from deep within his chest. The blond could feel his filling cock, rigid and ready against him which sent a shiver down his spine. He wasn't a stranger to what was set to happen next, but once again, this was Kaigaku and he was a demon, an inhuman monster that fed on the flesh and blood of mortals.
Weakly, he attempted to slither out of the alpha's grasp yet again, managing to yank one of his hands free. Immediately, he began clawing at the alpha's hand in an attempt to get his other free and possibly make an attempt to escape, his legs kicking out and trying to find purchase beneath the impossibly heavy weight over him.
At least, that was the barely formed plan Zenitsu had put together before he felt sharp teeth over his mating gland and heard an irritated, bestial growl from the alpha. He stopped in an instant, his limbs going limp and his eyes going wide.
Once he was satisfied that Zenitsu was pliable once again, Kaigaku pulled his mouth off of the blond's neck and snarled at him, "Try anything like that again and I'll kill you."
And Zenitsu knew that it was not simply an empty threat.
There wasn't much time to get his thoughts together or put together another plea towards Kaigaku's better nature (not that it would've helped or had any effect at all) as the demon shifted his weight off Zenitsu freeing his wrist and using that hand to hold himself up with a clawed hand aside Zenitsu’s head, giving him a good look at him deadly, demonic talons. Zenitsu had no sense of where he'd placed his other hand, though he could feel the absence of it shoving his face to the floor. But he didn't have to wait long to find out as he let out a strangled cry.
Kaigaku had apparently decided that the rest of Zenitsu’s clothes had to go, impatiently ripping them off without any care whatsoever. He had enough strength from his inhuman boons to pull the fabric right off of him, tearing him at the seams, though he was also careless enough to allow his claws to rake down the blond's back in his haste. It didn't matter much to him whether Zenitsu’s flesh stayed intact anyways since he planned to dispose of him after he got what he wanted.
Blood beaded up through the angry red marks and they burned, a stark contrast to the icy cold dread that had settled into his limbs. He could hear the way it enticed the demon, the way he hesitated as he inhaled the concoction of scents pouring off Zenitsu’s body. A bleeding omega this close to his heat must smell like a feast fit for only the greatest of lords to a demon.
The rest of his clothes didn't last but a moment longer before they too were shredded and discarded. Zenitsu shuddered as the rest of his body was exposed and left vulnerable, devoured by Kaigaku's hungry gaze, and yet shamefully, he felt another dribble of fresh, hot slick roll down his balls.
No matter how much he protested, Kaigaku’s desire would not be derailed, for every plea he made was countered by the heady draught of pheromones that screamed over him, ‘Breed me! Mate me! Fill me with your pups, alpha!’
Formalities weren’t going to last much longer. The sounds of shuffling fabric were all too loud in Zenitsu’s ears, rising over the pounding of his own heart and his terrified, shuddered breaths. If he didn’t do something right now, he was going to be raped! But what exactly could he do? His Nichirin sword had been secreted away by the demon over him and with his omega instincts taking over as his heat kicked into full-drive, it was becoming harder and harder to fight back. The time to act was now while he still could.
While the demon was distracted with claiming his prize, Zenitsu took a shuddered breath and summoned all his remaining strength to kick out at the monster, hastily wriggling out of Kaigaku’s grasp to escape him. His heart pounding in his ears like the beating of drums, the noise building up with the anticipation that he would soon be dead. There was no escape but he had to try. He had to get out of here. He just had to!
It didn’t take long for Kaigaku to pounce, landing a painful blow in the middle of his back, pinning him to the floor with a furious snarl. “You brat! I told you to stay put!”
“No way! Get off me! I don’t want to do this!” Zenitsu cried, struggling under the demon.
Seeming to have grown frustrated with him, Kaigaku let up on the blond and roughly flipped him on his back, putting them both face to face for the first time thus far. Zenitsu got a good look at him in the pale moonlight, at the dark markings on his cheeks, at his bloodstained fangs, and at those shining turquoise eyes that pierced through the darkness, chilling and inhuman. If in any case there had been any doubt in his mind that his attacker was anyone but his adoptive sibling, it had been put to rest after setting his sights on what was quite clearly Kaigaku’s face and fastened around his neck, Kaigaku’s pendant that he was never seen without.
Fully peering into those eyes, some of the fight seeped out of Zenitsu’s rebellious limbs. He may have looked different, and maybe he smelled a bit different, but it was still him. It was still his Kaigaku. His nii-san. Even as battered and beaten as he was by this very same man – well, demon – Zenitsu’s body longed to have its heat quelled by someone familiar, though at the same time, he couldn’t help but be pushed to tears.
“Kaigaku…” He murmured, staring up at the demon as tears began to well up and roll down the sides of his face. There wasn’t anything else to say. Nothing else that could be done. This was going to happen and he was powerless to stop it. Anything he decided to do would render his desperate attempts to be completely useless as he was subdued yet again.
The monster over him glanced away and a mix of emotions played out on his face before he looked back into those eyes again with a scoff. “You really are the most pathetic person I’ve ever met,” he huffed, but the decisive, certain tone he’d had before had melted away as though this was no longer an insult but a twisted endearment.
Zenitsu tilted his head and cast his gaze to the side with a sigh. Would it really be best to just let Kaigaku do as he pleased to his body?
No. It definitely wouldn’t. Even if it meant he was going to die, he had to at least try to fight back. Whatever strange mix of feelings kept trying to come to the surface – present in both of them apparently – needed to take a damn hike! He wasn’t going to let this happen. He was going to fight tooth and nail.
Summoning that inner strength, Zenitsu lashed out, kicking and shoving and yelling at the demon, his fight still alive and full of strength.
“Are you serious right now?! Give up already!” Kaigaku snarled, but Zenitsu did not give in, shaking his head furiously as tears began to run hotly down his cheeks.
As cute and inspiring as this display was, the demon had already grown impatient enough and though annoying, Zenitsu’s attempts to save himself meant nothing. They weren’t going to save his chastity. Not here and not now. He had been doomed from the moment the sweet scent of his impending heat rode on the breeze all those days again, enticing Kaigaku to take what should rightly be his.
With a deep, throaty growl, the demon grasped one of Zenitsu’s wrists and pinned it painfully to the floor, hard enough to make the bone creak and Zenitsu cry out in pain, forgetting his mission and immediately diverting his attention to his pained wrist to get it free before Kaigaku could break it. That ought to keep him distracted until he could carry out his own task.
In a smooth motion, Kaigaku pressed his knee between Zenitsu’s thighs and split them forcefully apart.
Zenitsu suddenly seemed to recall the part where Kaigaku had been wanting to slip into that dripping wet ass of his, but there was nothing he could do now. Kaigaku had managed to shove his way between his thighs and now that he was here, he no longer needed to abuse the blonde’s poor wrist. He let him go as he hiked up one of those delicious thighs, creamy looking thighs – he’d have to mark him up later – and with his other hand, he took his cock in his hand, pumping the twitching, excited organ once, twice, and pressed it against the tight, slick hole.
“No! Please, Kaigaku! Please, don’t do this!” Zenitsu pleaded with a whimper, his eyes fixed on the demon’s face, holding his limp wrist to his chest. His brows were drawn together and his voice quivered as tears leaked and spilled out over his cheeks with seemingly no end in sight.
But Kaigaku didn’t stop. He pushed in, pressing inside past the tight ring of muscle that insisted on keeping him out and getting in his way. It was scorching hot and squeezed him so enticingly that for a moment he wondered why he’d never taken Zenitsu’s ass before. He could have had him at least a hundred – no, a thousand – times over by now if he had just taken him when the boy had first presented as an omega. And it wouldn’t have been nearly as difficult to pin him down and fill him up with his knot back then. The first heat was always the worst after all and he could have easily broken into Zenitsu’s room to breed the heat out of him and turn him into the perfect cocksleeve he was born to be.
Zenitsu cried out and proceeded to sob, his eyes glistening with tears. “Stop! Please, stop! It hurts!” Kaigaku, however, ignored him. He couldn’t help it. It was like Zenitsu’s ass was drinking him in, swallowing him up, just begging to be bred and so very tight.
He canted his hips against him, driving his cock deeper into the scorching heat.
“For a crybaby, you sure do make a good fuck,” Kaigaku taunted him, receiving only a chorus of pleas for his trouble.
“That was a compliment, you worthless, omega rat! That’s not how you respond to a compliment!” He dug his claws into Zenitsu’s succulent flesh, drawing a scream from him. “What do you say to a compliment?”
“Th-Thank you, alpha!” Zenitsu squeaked, shaking.
“That’s right. Good boy,” he praised him, sliding his cock from his hole and driving back in just as deep. Why had he never taken him before?
Soon enough, he was thrusting and pounding into the fluttering hole, forcing delicious sounds out of the omega, growing in pitch and frequence. His knot was beginning to bulge, growing and pushing against the slick, abused entrance, demanding its own entry. Kaigaku would be crazy not to allow it and breed up the little whore. He obviously wanted it.
“No, please! Don’t knot me, nii-san, I-”
Again, Kaigaku dug his claws into his captive. “Did I fucking ask for your opinion? Now shut up and fucking take it!”
Blood welled up to the surface in thick droplets and Zenitsu began crying in full, sobbing his pathetic little eyes out. But he felt so good, especially when Kaigaku’s filling knot breached and his balls tensed, emptying their foul seed into the omega’s womb with a groan, locking him inside of the blond boy’s clenching hole.
Kaigaku ripped his talons from Zenitsu’s battered body and began to lick them clean as the omega sobbed. He’d get used to it soon enough, because now that he’d gotten a taste, he wasn’t leaving until he’d licked the plate clean. His cock twitched at the implications and he grinned maliciously down at his victim, unaware of the remaining horrors he was to face.
Oh yes, Kaigaku was going to enjoy this.