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Kokushibo wasn't entirely sure why he kept spontaneously checking in on his younger twin from time to time. If anything it was an annoyance, like a pestilent thorn in his side. Having to stay far enough away to avoid being on the receiving end of the superior brother's blade, but close enough to seeth.
Initially, it was to revel in Yoriichi's obvious misery. Forced to live with the demise of his dear Uta and unborn child.
Before becoming a demon, Kokushibo had heard the entire sob story. One that had once filled him with indifference, almost made him crack a smile at the thought.
Loving every second of the widower's downfall, but then you came along. A seemingly sweet, pretty little thing. The kind of beauty that only visited men in their dreams. Possessing a heart so gentle, poets would wish for you to be their muse.
Instead, Yoriichi had somehow managed to weasel his way into courtship. And after he failed to save your parents too.
It was infuriating.
Sure, the melancholy was still apparent in Yoriichi's aura, but now, even he had begun to smile more often. It unnerved Kokushibo to no end.
So why couldn't he look away?
Overlooking the humble property on the horizon in a jealous rage. Watching you scurry along inside like a frightened mouse. That damned Yoriichi must've told you about demons, and to avoid being caught outside after nightfall. As if a door could ever stop a demon.
Away, without you by his side. Making the mistake of leaving his beloved alone again.
When would he learn?
Kokushibo's fingers curled at his side, veins protruding along the back of his hand as his grip tightened. Knuckles now a sheer white, hands verging on trembling. It was just so infuriating. Why did Yoriichi have everything?
He had effortlessly surpassed him in skill, and now he had a beautiful bride? One that he managed to actually care for.
Kokushibo never had that, his marriage was a politically driven arrangement. It had only been a few years since his departure, but his wife's face had already grown stale in his memory. She certainly wasn't hideous, but a pretty weed doesn't compare to the rose.
Remembering that over time he had grown to care for the wife he had long abandoned, but nothing like what Yoriichi had with you. Actually having somewhat of a choice in who to take in matrimony. If anything, Kokushibo thought of his wife as more of an acquaintance he had a duty to bed.
As far as he could tell, Yoriichi hadn't even bothered to take that step seeing as he was still courting you. A single act of penetration and you'd be bound to his brother in marriage.
Yoriichi was able to take his sweet time, nurturing and fostering your relationship. Whereas, Kokushibo, had been expected to produce an heir at the age of sixteen with a woman he hardly knew.
It wasn't fair.
Envy seized his chest, festering inside his heart the longer he stood there. Filling the organ with a toxic tar, with each silent beat.
He reached for the handle of his sword, fingertips grazing the surface near the hilt, but stopped. It would be so easy to kill you.
Too easy.
No.
He had other plans for you.
With Yoriichi away, your heart practically leapt out of your chest.
Pounding rapidly with fear, the rhythm of its stuttering was practically unbearable. Shaky hands growing cold and clammy with anxiety. Sweat building up along your palms as you wiped them on the smooth fabric of your sleepwear.
Every shadow appeared as though it had a story to tell, unlike on nights where your fiancé was home. With him nearby, the shadows were simply just shadows. You could be completely at ease. knowing he'd protect you.
How could you not be when he not only saved you from a demon, but from a predatory marriage set up by your next of kin. With you orphaned and unwed, the only logical next step was marrying you off.
Upon hearing this, you begged for Yoriichi to take you as his bride. Only wanting to marry your savior, not some perverted, older man.
He held some reservations towards the prospect of marriage, having been married once before. Finally agreeing when you made him realize that perhaps he did deserve a second chance at love.
Slowly warming up to you, the inside of your stomachs fluttered more like a butterfly's wing with each passing day. Your engagement being the spark, time only fanning the flame hotter.
Even though he still felt that he didn't deserve something as pure as love, he couldn't deny it. He couldn't deny you.
Holding Uta close to his heart while still allowing you into his vulnerable heart. With the history still so fresh it wasn't as though it could repeat. Nothing could go that wrong again, could it?
Surely he had learned from his mistake.
Maybe he was worthy of love. You sure made him feel that way.
Yet every time you attempted to initiate the consummation of your marriage — becoming one in the flesh — he declined. Still unable to give his body to a woman that wasn't Uta. That part of him still belonged to her.
As much as it pained you, you understood. He had gone through the unimaginable.
So when you finally settled on your futon, in a cursory slumber, you were pleasantly surprised to feel a familiar body holding you. Pulling your lower body down to his hakama, resting the curve of your rear end along his pelvis.
You had hugged Yoriichi on numerous occasions, but had never felt THAT. It wouldn't be improper, seeing as it was the final step finalizing your marriage. But how was it supposed to fit anyway? It was a weapon in its own right.
Stirring, still half asleep, you brushed against his groin again. This time reveling in the thought of finally being completely desired. Before that moment, you had thought Yoriichi was only content to share his life with you.
But now..?
No wonder Yoriichi had been putting off intimacy greater than a hug or the sparse kiss. But, he knew his strength, and he wasn't supposed to return for another day.
This wasn't your beloved. It was an imitation.
Pyrite, not gold.
You froze, breath catching in your esophagus as a commanding, tepid hand reached beneath your clothing, cupping your unbound breasts. The touch wasn't gentle like how you had imagined your soon to be husband's. Rather, it was almost domineering. Firm, but not quite rough.
This wasn't foreplay; this was an assessment — almost medical.
“Yoriichi,” You whispered into the dark, wanting your gut feeling to be wrong.
Hoping, praying that it was actually him.
“No.” The implication that you could mistake him for his vexatious, younger brother was maddening. An insult he could not overlook.
His large hand squeezed the soft tissue of your breast as a warning, not a punishment. Relinquishing a minute amount of force exerted upon you only when he heard you emit a breathy whimper.
You would not make the mistake twice.
Slowly, you rolled far enough to catch a glimpse of the creature's face in the dark. He looked so similar to Yoriichi, give or take a few eyes. A demon, Yoriichi's older brother.
You knew very well that a battle brawn would be in vain. A pointless endeavor that you saw no point in pursuing. So, you'd have to rely only on your wit.
“My apologies,” You struggled to relax as he continued to assault you. His large hand moved to inspect your other appendage.
Breath wanting to hitch again, but you refuse to allow your lungs even a moment to stutter. Remaining quiet and poised. Refusing to show even an ounce of weakness.
Your heart rate however, could not lie. He could see just how frightened and tenuous you truly were. But there was a spark lingering inside telling you to fight. Mentally, he applauded your ability to not completely shut down. To not give into weakness.
How you merely presented yourself as a nearly frozen fawn to an apex predator.
Allowing him to further pull apart your clothing, the frigid night time air erecting your nipples. Body involuntarily squirming, writhing against the cold in a way that he almost found amusing.
Kokushibo didn't acknowledge your silent pleas. However, he did find your atonement adequate. Not befitting of someone wishing to carry the Tsugikuni name, but that wasn't your name yet, so he could overlook imperfection just this once.
Of course Yoriichi had neglected teaching you proper wifely etiquette. He never quite fit the mold of what was expected of him. Kokushibo knew how to be a proper husband if he felt inclined to play the part. So he was better suited to discipline you into an acceptable wife.
He had already planned on stealing your virtue. Leaving you in shambles to explain to Yoriichi that his would-be wife had become spoils of war claimed by his elder brother. But something told him Yoriichi would still pursue marriage with a whore.
So, Kokushibo would claim you as his wife instead. Stealing as much from Yoriichi as he possibly could. Wishing to completely devastate his younger twin into faltering.
He could've taken you as a pet, plenty of other demons did that with beautiful humans. Little toys they would play with and eventually break then discard like trash.
An act positively beneath him.
A wife was more befitting of someone yielding his strength. And you were a commoner woman, a peasant. He didn't owe you courtship or ceremonial rituals. Consumation was enough.
Kokushibo gave your breast a final, harsh squeeze. Lips nearly vurving upwards in satisfaction.
Yes, they were more than adequate for nurturing any potential off-spring you conceived. Be it demon, human, or the fabled hybrid his lord was searching for. One that could withstand the sun and be absorbed for its ability.
“Undress,” He commanded.
Your face remained still as you unraveled your clothing for your brother-in-law. Giving yourself grace by closing your eyes and pretending it was Yoriichi. They were similar enough in both size and stature. Kokushibo's muscles were slightly more enhanced and robust, whereas Yoriichi was a little leaner.
It was the facial features that made it obvious that the man wishing to bed you wasn't Yoriichi. Your heart winced as you snuck another peak at his face only to be met with golden irises and red scalia, rather than reserved maroon.
As you discarded your clothing, Kokushibo lowered you down to the futon. Resting his hands experimentally over your hips. Not as though he were inexperienced, but as another examination. Fixating on your hips and how you would fair in birthing him an heir.
Fully intending on stripping Yoriichi of the family he so desperately desired.
If Lord Muzan ever inquired as to why he took on a wife, he could explain it away as preventing Yoriichi from passing along sun breathing. That he himself wanted you to bring forth a son for him to teach moon breathing to.
Your face burned, body now fully exposed to the demon. Thighs clamped shut and arms crossed over your chest to preserve what little modesty you had left.
Claws continued to creep over your hips; this time focusing on your pelvis. This you understood. He wanted to calculate the odds of you surviving childbirth.
There was always the option of cutting into your womb through your stomach should your hips prove to be too narrow, but major abdominal surgery was practically a death sentence. Or in this case, worse than a death sentence.
“Good.” His praise was minimal, but got the point across, “Spread your legs.”
As you forced yourself to meet his demands, your bottom lip began to wobble. Quivering in fear but remaining fixed shut. Kokushibo could easily spot this blemish of weakness, but in your weakness was a strength he found oh so alluring.
You didn't thrash, or scream, or beg. No, you just accepted your fate with resigned poise. Much more preferable than listening to broken sobs.
Maybe one day when your loyalties had shifted, he would thank Yoriichi for practically handing over his bride. Once you realized Yoriichi had failed to protect you, you'd realize that only wanted him.
“You're a virgin,” He stated plainly, using the transparent world that your fiancé has taught him.
You confirmed it with a single, hesitant nod.
“You understand what happens when this is over then?” You could hear the near silent sound of his clothing rustling. Refusing to look at him.
Your body froze in fear, muscles tightening, rejecting him, “You'll kill me.”
“No,” He pried your thighs further apart. Showing you once again how futile fighting someone like him would be, “You will become my wife.”
Tears pricked at your eyes, wetting your lashes, but you refused to let them fall, “Very well.”
The fat tip of his cock pushed past the entrance of your unprepared cunt. He did so slowly, in control of his actions. This was calculated, not simply an act of lust.
There was a strategy to this. He was measuring how much discomfort your body could handle before fully plucking away your final shred of innocence. Nudging into that thin tissue, rocking his hips just hard enough to tear it.
A small trickle of blood dripped past your aching hole. Coating his cock, staining your bedding. The amount of blood was rather miniscule, but it was enough for Yoriichi to realize what had happened upon his return.
For a moment you could only see blinding white light. Velvet walls clenching around him, trying in vain to reject his intrusion. The rest of your body went limp, unable to fight him even if you wanted to.
With lidded eyes, you were able to fake an image of Yoriichi instead. This was supposed to be him when he was ready; not his twin brother.
The demon mounting you was very intentional with his thrusts. Heavy enough to invoke his own pleasure, gentle enough to lessen your pain. You supposed he'd want you to be thankful for that. Many other demons or even men would ravage a war bride — this one didn't.
Your resistance towards him was obvious, despite your uncombative state. From above, he could see how your body gave it away.
Your facial muscles would tense and relax with the rock of his hips. Fingers curling at your sides, searching aimlessly for a bit of fabric to cling to. Your thighs trembled against his hips, not shaking quite like a leaf, but not exactly like prey playing dead either.
Each breath was shallow, a sharp inhale through your nostrils. The scent of his musk wasn't even unattractive, that was the worst part. It was vaguely similar to Yoriichi's, but was still distinctly different. Another reminder that it wasn't him, no matter how hard you tried to pretend.
“It'll hurt less if you quit holding your breath.” Kokushibo's voice wasn't gentle, but his words almost were.
With that, his hand dipped between your bodies, finger tapping against your clitoris. He grunted in satisfaction as a faint whimper vibrated against your vocal chords.
Purposely providing a woman pleasure was something he was far less experienced in. Sure, the wife he had since long abandoned would occasionally moan for him, but he never touched her in a way outside of their line of duty — reproduction.
Only tipping back your clitoral hood and rubbing your bundle of nerves due to reasons rooted in jealousy. The thought of making a woman promised to Yoriichi cum for him instead was certainly appealing.
“Mm,” Your face shifted to the side, cast aside in shame that he was making you feel good.
Not Yoriichi, him.
For the first time in forever, he finally felt an air of superiority over his brother. You were already surpassing your predecessor in bed. Even growing wetter than she ever had despite your wavering resistance.
Your body was beginning to betray you.
Hands instinctively wrapping around his neck, clawing at his trapezius. Under different circumstances, he would've corrected that behavior. But he decided to be lenient, knowing you'd have eternity to learn how to become a proper wife.
By the quaint appearance of your home, he could assume that you were illiterate. That would quickly be remedied with tutors and physical reprimands if need be.
Any peasant could breed, and from Kokushibo's assessments, you would do well in that regard. As a woman, you naturally would know how to nurture any children he sired. So at the very least, that wasn't a concern.
With each stroke of his finger, your body began to physically desire him more and more. Your mind was still slipping into a protective shield, allowing you to pretend it was Yoriichi touching you instead.
Your lower body tensing as he drew circles into your clit, getting the hang of the previously foreign motion. Intently observing how your body reacted to his own. Slowly but surely you were becoming even wetter for him.
Your now soaked, molten cunt squelched for him. Moistening the dark hairs surrounding the base of his thick cock with your essence. A surefire sign to Kokushibo that you wanted this too.
He could sense it in your sordid pheromones. Your ripened body writhing beneath him, like the most beautiful seductress. This wasn't a lapse in judgment, nor folly though.
This was fate.
Subtle, saccharine moans began to spill out as heat pooled in your lower abdomen. Tightening like a coil with each brush against your puffy nerves.
“Beautiful.” Despite the fact that he was admiring you — praising you — his gruff voice remained stoic.
You knew better than to ignore a man who was speaking to you, “T-thank you.”
Yes, you would serve as a fine wife indeed. Polite even when in distress.
You felt the tip twitch inside. Perhaps he was almost done? Was there a way to speed up the process?
Against your better judgment, you let go. Releasing the safeguard of your mind, focusing only on fawning for the demon abusing your virgin cunt.
Not really sure what you were doing, but willing to try anything. Gazing into the middle set of those golden eyes with heavy lashes in the way women would quietly gossip about when alone.
Their experience would aid your inexperience.
The whimpers and moans he pulled from your throat were very real, TOO real. He had your thighs pinned to your torso in some kind of mating ritual. Bearable, but uncomfortable. Something you could endure.
Plunging deep inside with each brutal thrust. The tip kissing your cervix in a way you swore would break it under anymore pressure. Pained tears slipped down your flushed cheeks in tandem with strained, wanton mewls.
Why were you enjoying this? It was a betrayal like no other. Disliking it was one thing, enjoying any portion of it was another. The shame allowing suicidal thoughts to slowly envelope your mind. Only pushed down with your impending orgasm.
A nail in the coffin.
“Ohh!” The sensation was practically blinding, your release ripping up your spine like a crack of electricity.
Your nails dug crescents that would heal almost as fast as your touch vanished into his pale skin. Holding onto him for dear life.
In comparison, you were far more delicate, his fingertips gripping your skin painfully. Sure to leave bruises when you woke up from this nightmare in the morning.
A low hum resonated off the chords in his larynx in satisfaction. Enjoying the way your creamy, fertile pussy spasmed and gripped him like a vice. Like it was made to take his seed.
The sound of heavy balls slapping against the curve of your ass echoed in the room. Harmonizing with the weak melody of your lament. A grieving requiem of what could've been.
Your whole world going dark and crashing down as he gave a final thrust of his hips. Marking his territory with the semen flooding your womb. Never in your life had you felt so full. The sticky substance was thick, almost extrinsic.
To your knowledge, demons couldn't breed, and if they could it was rare. But something told you that he in particular would prove virile. A gut feeling told you his seed was potent.
As he withdrew, you felt empty. Wrecked, weeping hole clenching around nothing. The shattered pieces of your heart were heavy, slipping through your fingers into a free fall.
Repairing was impossible, rebuilding improbable.
Proven with his final command of the night, “Dress and come with me, wife.”
Leaving behind only the wreckage of disheveled bedding behind. Taunting Yoriichi with the stains of blood and betrayal he would soon find.