(This 2nd part was requested by & enjoy!)

~3rd pov~

Everything was horrible after the night with Muzan. Y/n couldn't sleep, think, or even eat regular food anymore. It was tasteless to her. Snarls ripped out of her throat as she laid in her bed.

She couldn't stand it. He mixed his blood with her, she knew what he has turned her into. She got up and grabbed her sword and got dressed, she left her little room and out to the woods.

She remembered when she came back, she immediately wanted to learn Tanjiro and Rengoku's breathing styles to add more power to her own. She also wanted to learn from Gyomei and Tengen along with Kanoe.

She was going to execute Muzan. But she needed him to fix her first before she killed him. She knew she had to.

A different demon? What did he mean by that?

If she is to defeat Muzan. . . She'll need to learn the best of the best breathing styles.

Sun Breathing.

Yoriichi Tsugikuni, her great-great-great grandfather. . . She could mix the Sun with her Roses.

Ironic, wouldn't that equal Sun Flower Breathing.

Suddenly, a vision appeared before her eyes. A figure that was speaking inaudibly to her, she looked at his mark and saw his earrings.

"Yoriichi?" She muttered.

She couldn't understand what he was saying to her. He remained there and finally she read his lips.

'He is behind you!'

She snapped out of her vision and turned around just in time to defend herself against the demon.

": Crimson Rose-Focus!!"

{The Demon Slayer charges towards their opponent, making use of small yet rapid steps to hastily cover ground in order to approach their opponent. As the Demon Slayer finally gets within their preferred range of attack, they will rotate their body while unleashing two devastating slashes, essentially becoming a spinning embodiment of death.}

She didn't miss and managed to slice off his left leg and arm. Almost half of his entire body.

"Y/n, don't fight me-"

"WHAT DID YOU DO TO ME?!! CHANGE ME BACK!!" She yelled.

He sighed and let his body morph into a pale color, his hair grew white and long, different demon like mouths appeared on his legs and thighs, arms and shoulders.

I held my blade tightly as I stared at him.

"You really shouldn't get on my last nerves." He growled.

"I'll make you pay for what you've done to me."

"Come and get my check then." He scoffed.

Muzan has weak spots. Seven hearts and five brains that move freely around his body. She studied all the demons and even tortured most of them to find out what Muzan's weaknesses were. Kokushibo was a great demon to get answers from.

She was slowly growing more and more unhinged as she grew angry at Muzan.

She knew Yoriichi combined all his forms into one strike which turned his blade bright red, enabling him to cut through all of Muzan's weak places and overpower him.

She had practiced the full 13 forms to defeat Muzan, but she forgot which combination they went in. Right now she had to weaken him.

Spine like tentacles erupted from his back as they shot straight towards her, she dodged one and was sliced in the arm by one. She moved and stayed agile.

"Tenth Form: Spirit of the Rose!!"

{The Demon Slayer unleashes a horizontal slash, promptly raising their weapon into the air before unleashing three downwards slashes, this technique aims to allow the Demon Slayer to channel their full strength into the downwards slashes as to easily cleave through whatever they may be aiming at.}

The strong waves of slashes immediately shot straight at Muzan, slicing and cutting through the tentacles like nothing and hit his chest.

He used his speed to charge at her and came too close, she saw his arm raise to grab her throat.

": Blossoming Rose Petals of Clarity!!"

{A form created by Y/n that can only be used to it's maximum potential by a wielder of the Red Rose; The Demon Slayer will preform a rapid series of rotating sword slashes that act as a shield and defend them from any attacks whether they be ranged or physical and close ranged. When preforming this form, the Slayer's eyes work hand in hand with their arms with more focus placed onto them which allows the Demon Slayer to see attacks slower and prepare when they actually come and their arms move at fast rates to where it doesn't even seem like they have moved their arm at all from one position and due to the speed and strength being placed behind the form, wind slashes form along the blade and surround the Demon Slayer like a barrier, slicing through any limbs that are used in a physical attack and blowing ranged attacks away.}

Muzan's arms were missing but immediately appeared after two seconds. He was almost taken aback by her attacks. She prepared for her final blow. My 12th form.

He snarled as he charged at me with different abilities appearing around him.

"Twelfth Form: The Rain of Rose Blood and Thorns!!"

{A form created by Y/n's father that can only be utilized to it's maximum potential by a wielder of the Sun Blood Rose. The Demon Slayer inhales deeply and flexes their muscles as mist surrounds them and the enemy, concealing her presence while placing focus onto senses so she can vividly sense every move and predict it, dodging and counter slashing with every step as she essentially moves unseen at rapid paces continuously. Red roses and vines begin to also grow around her arms and legs as she moves for the attack.}

The mist surrounded them both, he couldn't see but felt his legs and arms, all his weapons and attacks failing as she attacked him.

He saw the vines and rose petals floating around in the mist. He grew back his limbs and managed to snatch randomly in the mist, luckily grabbing onto her.

Her arms having vines and loose petals falling, she snarled as she kicked his waist, actually hurting him for a change.

He snapped his fingers and the same hot heat triggered her again she fell onto her back when he let her go.

"AAAAGHH!!!!" She screamed as she crawled weakly away.

"You didn't give me time to trigger the bomb within you." He laughed.

She was hunched over as she snarled and drooled, her teeth growing fangs and her eyes glowing in a sharpening red color just like Muzan's.

"Now your under my control again, you liked the way I treated you last time. Succumb to me and become my mate for all eternity." He said before touching her shoulder.

She growled like a demon before looking straight at him.

"Hmm, turned on I see." She unwillingly clawed his legs and bit his stomach.

He held her face and grew an erection, it pressed on her lips. She took him in with hunger, she held his sides as she used her demonic tongue to swirl and suck on his cock.

She shoved him down and continued to lick his length, his hand held my head and shoved me down on his dick. She growled at him as he sat up and groped her rear end, he moved aside underwear and fondled her soaking folds.

She crawled to his face and made him kiss her, Muzan was shocked by her strength. He tried to make her unhand his neck but she didn't let go, she shoved him on his back and straddled him.

"Hey wait a second- FuCk!!" He gagged when she kissed him and sat on his cock.

His claws dug into her waist and drew blood, she bit his lip before rocking her hips. Her head fell back as she took his entire dick inside of her, Muzan gritted his teeth as she began to bounced on him. Before he could even move, she pinned his hands above his head, she bit his neck and moved her hips even more.

Growing faster with the movements. Muzan snarled as his white hair grew messy, Y/n kissed his lips and didn't let him go. He managed to overpower her and flipped her on her back, beginning to rail her into the grass.

She drew blood from his arms as she let him have his way, she was tight and warm around Muzan. He kissed her neck and let her bite his shoulder, he snarled as he held her hair out of the way.

He licked the rose mark on her cheek and made her kiss him. Muffled moans vibrating in her throat as Muzan rolled his hips, he was close to breaking, he made himself grow larger inside of her.

He covered her mouth as she tried to scream, he opened her shirt and bit her breasts. He continued to drill himself in her and licked her chest, his hair tickling her skin as he continued. Her legs were shaking, vines began to intertwine with his arms and legs, blood dripping but also sweat and drool.

He kept going and stopped holding back. She showed her demon fangs and growled like an animal

Y/n let out a low hiss as she finally came, Muzan growled as he bit her shoulder down and held his cock inside of her before cumming deep in her. Filling her up with semen, it was like a reward for Muzan. But the semen was the cure Y/n needed from him.

He panted as he rolled onto the ground beside her.

"I told you, you couldn't resist me. . . Be my bride, Y/n. . . Leave the Hashira. . ." He said.

He looked to his side but didn't see her.

": The Dance and Raging Sun of the Blazing Petals from the Burning Red Rose!" She shouted.

{The Demon Slayer continuously performs all twelve forms of Sun Breathing and the Rose Breathing in repetitive succession to increase the accuracy and agility of its movements while reducing fatigue. These two forms were created solely for the purpose of killing Muzan Kibutsuji, since the repetition of all twenty-four forms aims to destroy Muzan's twelve vital organs. Only one out of five Demon Slayers could managed to use these forms.}

Her blade and body were agile and quicker than Muzan himself, in one final and big blow.

Her cold metal blade sliced right into his head, splitting his body in half.

Finally. . . Destroying his weak spots. And ridding the world of Muzan Kibutsuji.

Or so Y/n thought.

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Hope you enjoyed! Stay tuned and seeya soon guys gals and non binary pals 💜💙💖