Slayer of the Night (Demon Slayer x Hashira Reader)

Ch8- Strike of the Hashira: Death's Dance with Muzan

     In the heart of a desolate land, a fierce battle was about to take place: a duel to the death between the Night Hashira and Muzan.
     (Y/n) had faced many strong opponents over the years, but none had motivated her as much as Muzan, an immortal madman who had been wreaking havoc on the land for centuries.

    (Y/n) was determined not to let history repeat itself and was desperate to take Muzan down once and for all.
     Darkness blanketed the destroyed forest, only pierced by the dismal glow of the moon. Like an infinitely twisted chess-board, the ground clothed in rubble provided the grim battleground.

     (Y/n) picked her way across. The scent of blood was overwhelming, a Portent of the daemon, Muzan Kibutsuji, that she was fighting.
    (Y/n) clutched her Nichirin Sword tightly, its moon-touched blade a stark contrast to the surrounding darkness. Her heart pounded as anticipation coursed through her veins.

     All her life had led to this one moment, the final confrontation with the beast that had ruthlessly slaughtered so many, the monster that needed to be subdued by his marital skill.
     With monstrous speed, Muzan lunged, a blood-chilling snarl escaping his lips.

    (Y/n), using the Breath of Night, maneuvered her sword with a precision that belied her anxiety. Her sword clashed with Muzan's wrist, and eerie sparks lit the darkness around them.
     Each collision was a shattering strike against the still silence of the night.

     Muzan retaliated with a volley of blood-demons from his flesh, forcing (Y/n) to weave her way around his attacks.
     Sweat ran down (Y/n)'s face, carving trails into the grime and blood on her skin. But, her determination never wavered. She pressed on, pushing her body and her abilities to their absolute limit.

     Her breathing forms, punctuated with graceful swordsmanship, began to tire Muzan. (Y/n) saw the wavering in his adversary's eyes, a novelty against the daemon's brutal power.
Is he...getting bored? (Y/n)'s face twisted into a dumbfounded expression.

     The nerve of this guy! Can you believe it? I feel like Tomioka when he is given an insult. (Y/n) huffed and shook the negative feelings and pressed on.
     Her movements a graceful and fatal ballet, etching death-markings around Muzan.

     Delivering the final strike, it was as if time had stilled. Her sword gleamed under the moonlight as it found home in Muzan. With a monstrous roar, Muzan erupted into an unholy mixture of dark blood and swirling ashes.
      Muzan grew silent, then smiled, his pointy teeth showed. He felt pleasure.

(Y/n) froze, eyes wide in shock as Muzan cackled with insanity. (Y/n) slowly lowered her head at her, staring at the sword that was punctured deep within Muzan's chest.
She looked a little lower and saw Muzan's fist had went through her stomach.

Her breath hitched as she felt blood trickling down her chin, but still felt no pain from the shocking state she was in. It only took a few moments to realize it: (Y/n) had failed.
Before the pain settled, (Y/n) stepped back. Her body screamed in exhaustion, her sword still clenched in sweat-soaked hands. Then, Muzan's form crumbled away, his reign reduced to momentary dust and faded nightmare as the sun had finally risen over the east horizon.

Muzan was finally gone. His remains have evaporated into nothing. (Y/n) let out a breath she hadn't realized she'd been holding. She fell to her knees, her grip loosening around her sword as it clattered to the ground.
A feeling of guilt and pain washed over her as tears streamed down her face, mingling with the endless grime of battle.

She won. Muzan had finally been defeated after decades, the ghosts of his past victims can finally let go and be released to Heaven with their loved ones. But (Y/n) feels as if she doesn't deserve such a victory.
She laid there against a tree, her lower body completely numb as blood continued to flow, already staining the grass red.

She felt as if she was about to hurl with swirling feeling she suddenly got in her stomach. She hesitantly looked down at the gaping wound she had received from Muzan's fist. It wasn't there anymore...
"What the hell?" (Y/n) gasped in disbelief as she stared at the healed wound. Pain suddenly washes over her body again as she felt immense pain in her jaw.

Sticking the tip of her finger in her mouth, she felt something pointy. Do I have fangs? That's when (Y/n) realized...she had been turned into a demon. "SON OF A—"