Muzan x sister reader

Gory(warning)

Tanjiro and the others watched in horror as Y/n drilled her nails in her head as she screamed her head off.

"Shut the hell up brat!!! You should just die and leave me be!!" She screamed out,  blood gushing out of her head as it stained no the her clothes and nails.

Y/n grips her hair as she bared her teeth, her fangs long and sharp. "You should just stay quiet and let me please him!!! Onii-sama loves me! Not you!!" She screams before dropping to her knees and banging her head on the floor.

Zenitsu turned to the side and held his stomach as he wanted to puke, the gory scene and blood with its metallic scent was overwhelming him. Especially since he could hear the bones as they cracked loudly.

Inosuke. . . Being Inosuke just stood still as he stared at the blood splattering all over the walls and floor. A cold sweat dripped down his face.

Tanjiro immediately gagged as the scent overpowered him, it was even worse since he had a keen sense of smell. Despite that, he urged himself to climb the platform and pull Y/n's collar away from the bloody floor.

He bites his lip as he slowly removed his hand from covering his nose and held her shoulders from bending down. He tries not to use his nose to breathe and only his mouth, but no matter what he did, the smell still lingered in his system.

Y/n looked up at him through her eyelashes, glaring slightly as she really wanted the brat to stay quiet, "Damn squirrel getting in my way" she frowned. "I can just have him stab the other heart—

"You were saying?"

The demoness grits her teeth rips Tanjiro's hands off her and jumps away. "Don't touch me so carelessly, squirrel. I'll kill if you do" Y/n growled, warning him.

"What if I made him stab your heart instead—

"Shut the fuck up brat!!" Y/n's creamed, surprising Tanjiro. After all, no one was talking.

"Don't you fucking dare! Onii-sama will torture you if you do!!" She screamed out as she glared at the ground.

"Oh S/n, Muzan-nii isn't here right? So keep quiet and let me take back my body"

"Don't you—

Tanjiro stared as Y/n screamed over and over, ripping her hair out before grabbing the knife from F/n's uniform and stabbing her left side of her chest. His eyes widen and immediately set out to stop her.

His hands gripped her wrist and pulled it away from her chest, the scent of blood quickly rushing to him to the point that his mind slowly wavered.

"Stop it Y/n!" He shouts, struggling to keep his grip on her. "T-this isn't y-you!" He groaned, struggling to keep her wrist till.

Y/n glared and tried clawing him with her other hand only for her wrist to be held by Tanjiro other hand.

At this moment, Y/n's mind exploded in anger. "What the fuck is wrong with you fucking squirrel?! Let me kill this brat once and for all!l she screamed, trying to pull away from the boy.

Tanjiro's eyes widen as he losses his grip on her. The second he did, her nails immediately went straight to him.

But before it could reach his skin, a hand grabs her wrist and pulls it back. "What are you doing?" A calm yet fuming voice asks.

The burgundy haired boy was washed over with relief when he heard the familiar voice, "Giyu-san!" He rejoiced in his head, his eyes sparkling.

"Another fucking bitch! Get your hands off of me!" Y/n shouts, trying to pull herself away from Giyu's iron grip on her wrists.

"What's happening here Kamado?!" Giyu urgently asked as he dodged Y/n's other hand.

"Um I don't know! We d-didn't know what caused this! Maybe the kakushis know or—

"Has she killed anyone yet?!" The male asks, just in time as he grabs her other wrist in place.

"Let go of me bitch!! I'll make Onii-sama kill you!" Y/n shrieked out only to be ignored by the two.

Tanjiro gulped, he felt his eyes sting as he glanced at the direction of F/n's lifeless body. "She. . .d-did" he says shakily.

Giyu's blood ran could as he gritted his teeth before quickly throwing Y/n on the floor and forces her on her stomach and holds her in place. His hands shook, his hands inched towards the hilt of his sword, wanting to kill the demoness.

His blank cold eyes stared at the struggling demoness. His heart thumped loudly in his ears. He didn't know why he was hesitating so much.

But before he could grab it, Y/n stopped thrashing around. His eyes widen.

As if time stopped, Y/n mover her head to the side, " "

As soon as she said that, his hands moved quickly to his blade and immediately unsheathed it before bringing it up and—

A/n

Sorry for the cliffhanger .