Demon slayer x Demon!Obanai sister!Reader AU {Prologue}
*Warnging Spoilper of Obanai´s past*
If you already know Obanai´s past then that´s great but if you don´t know Obanai´s past then like me tell you:
Obanai was born into a clan of thieves who lived off an excessive amount of riches that had been stolen from those who had been killed by the Demon that they worshiped. This Demon took the form of a woman with a snake-like lower body and face, and had a great taste for newborn babies, which is what the family sacrificed to her in exchange for their riches.
As the first boy born into the family for 370 years, Obanai lived out all of his days locked in a wooden cage being spoiled by his family, who insisted on bringing him so many plates of rich food that he became sick of it due to the overally pungent odors of the food and the poor ventilation of his room. The Serpent Demon also took a liking to Obanai, since he was a rare male child with heterochromia, and would spend the nights slithering around his cage in the dark and staring at him, which frighted Obanai so much that he couldn't sleep.
When he turned twelve, Obanai was finally allowed to leave his cell for the first time in his entire life. He was taken into a room that appeared to be an expensive shrine, and put face to face with the Serpent Demon for the first time, immediately causing him to shake in fear and terror at the demon's appearance and the realization that this was the very same thing slithering in his room staring at him every night of his life. The Demon remarked that Obanai was very small, and wondered to herself if she should wait to eat him until he was a little bigger. Deciding that she would, she organized his mouth to be cut wider, all the way to his ears, to match hers due to her "liking" him. The blood that he shed from this procedure was then collected into a chalice that she then drank from like fine Sake.
Obanai comes face to face with the Serpent Demon.
Back in his cell with his wound now covered by a bandage, Obanai began only to think of escape and survival upon realizing his fate. He began to scratch away at the lattice of his cell with a stolen hairpin he took from one of his relatives that he would then use during the night in order to prevent anyone from noticing his attempt to escape. Day by day he would be in a constant state of worry and fear and shaking in terror at the possibility of what would happen if the Snake Demon or his family would discover his attempt at freedom. The only being he could trust was a small snake that had somehow strayed into his cage and became his only friend, Kaburamaru.
Obanai is saved by Shinjuro.
After a while of doing this, Obanai finally manage to completely remove a wooden chunk of his bars and escape into the night as fast as he could. As he ran, the Serpent Demon began to pursue him, almost catching up to him and killing him before the Flame Hashira by chance came to his rescue. Because of Obanai's escape, the Serpent Demon had killed all fifty of his relatives and the only surviving member of his bloodline was his older cousin, who had also been saved by the Hashira. When they were reunited, however, Obanai's cousin rejected him and began to violently attack and claw at him due to her blaming him for their family's deaths at the hand of the Demon due to them messing up and allowing him to escape and screaming at him that he should have just let her eat him.
Due to these harsh words from his cousin and his own sense of self loathing and guilt for having been born into such a family and allowing them to die for his survival, Obanai joined the Demon Slayer Corps and decided to turn all his rage onto whatever Demons he could find, figuring that he'd feel like a better person if he risked his life for the sake of others and somehow ease his guilt.
Now that was his back story but I´m change it up since your gonna be his younger sister. You at least have to be somewhere in the story
My edit in Obanai´s past:
Obanai was born into a clan of thieves who lived off an excessive amount of riches that had been stolen from those who had been killed by the Demon that they worshiped. This Demon took the form of a woman with a snake-like lower body and face, and had a great taste for newborn babies, which is what the family sacrificed to her in exchange for their riches.
As the first boy born into the family for 370 years, Obanai lived out all of his days locked in a wooden cage with his few year younger sister Y/n being spoiled by their family, who insisted on bringing them so many plates of rich food that Obanai became sick of it due to the overally pungent odors of the food and the poor ventilation of their room. The Serpent Demon also took a liking to Obanai, since he was a rare male child with heterochromia, and would spend the nights slithering around him and his sister´s cage in the dark and staring at him, which frighted Obanai so much that he would hold his younger sister in his arms{Since they had no beds plus you were really small ;-;} as he couldn't sleep.
When he turned twelve, Obanai and his sister was finally allowed to leave their cell for the first time in their entire life. Obanai hold his youger sister in his arms as they was taken into a room that appeared to be an expensive shrine, and put face to face with the Serpent Demon for the first time, immediately causing him to shake in fear and terror at the demon's appearance and the realization that this was the very same thing slithering in his room staring at him every night of his life. The Demon remarked that Obanai was very small and so was his sister, and wondered to herself if she should wait to eat him until he was a little bigger. Deciding that she would, she organized his mouth to be cut wider, all the way to his ears, to match hers due to her "liking" him as she told them to let them younger sister be. The blood that would shed from this procedure was then collected into a chalice that she then drank from like fine Sake.
Obanai comes face to face with the Serpent Demon.
Back in his cell with his wound now covered by a bandage, Obanai began only to think of escape and survival upon realizing his and his sister fate as he stared at his sister sleeping on a pillow. He began to scratch away at the lattice of his and his sister cell with a stolen hairpin he took from one of his relatives that he would then use during the night in order to prevent anyone from noticing his attempt to escape with his sister. Day by day he would be in a constant state of worry and fear and shaking in terror at the possibility of what would happen if the Snake Demon or his family would discover his attempt at freedom. The only being he could trust was a small snake that had somehow strayed into his and his sister cage and became his only friend, Kaburamaru.
After a while of doing this, Obanai finally manage to completely remove a wooden chunk of his bars as he grabed his younger sister and carried her in his arms and escape into the night as fast as he could. As he ran, the Serpent Demon began to pursue after him and his sister, almost catching up to him and killing him before the Flame Hashira{Shinjuro} by chance came to his rescue. Because of Obanai and his younger siser´s escape, the Serpent Demon had killed all fifty of their relatives and the only surviving member of his bloodline was their older cousin, who had also been saved by the Hashira. When they were reunited, however, Obanai and his sister´s cousin rejected them and began to violently attack and claw at him as he protected his sister due to her blaming him for their family's deaths at the hand of the Demon due to them messing up and allowing him to escape and screaming at him that he should have just let her eat him.
Due to these harsh words from his cousin and his own sense of self loathing and guilt for having been born into such a family and allowing them to die for his and his sister survival, The flame Hashira separted Obanai and his sister from their Cosin and brought them into a town called Mist Town{Yes I made this place up} It was always snowly as when they got there The Flame Hashira asked Obanai if he wanted to bring him and his sister to a orphanage as Obanai looked a his younger sister sleeping in his arms as he looked back to the Hashira and shoke his head as he walked off bare footed in the light snow as he carried he´s sleeping sister. The flame Hashira smiled ¨He will be a great brother¨ as he left.
Obanai and you were homeless since you were both were still Children but Obanai raised you all by Himself. When it was snowing Obanai would wrap both of you up in a blanket as he would let you play with Kaburamaru. Anyone who would call you of ugly or say that his eyes were werid he would call them harsh words that would definitely hit them hard inside. Obanai would always think you were pretty and beautiful No other girl could reach you beauty, people envy you for your Beauty. Obanai was glad you were his little sister.
Even sometimes Obanai would say rude words to you or Hit you lightly on head if you ever made a mistake or did something he didn´t like. You had a honest and sometimes kinda rude personily but yet you were good.
As years grew Obanai wanted to join the Demon Slayer Corps as he now had a Trainer as the Trainer let you and Obanai live with him as he trained your older brother.Sometimes you´ll even see your brother train.The trainer was kinda old man but he was nice sometimes and hard to deal with was he leaved kinda from the Mist town as where he live it didn snow a lot.
when it was the time for Obanai to go to the final selection{Obanai´s rn is 16}. It was the worst desteion he made, He should have wait the next day to go.But Obanai left to go to the final selection he left you with his trainer and Kaburamaru as he trust the trainer with watching over you as he left. It was close to dark as the trainer told you he was going out shopping in a other town since not a lot of people are giving out food Cause the snow but he said he shall return before your brother comes back as he left you and Kaburamaru home alone:
¨It was getting dark as you were played with Kaburamaru as that´s when you hear to footsteps on the back door thinking it was Trainer coming back early. As the back door flew open as you walked out of your room to greet him as you saw a Unknown man whoś had black hair that was straighter and parted down the middle. He also wore a loose-fitting tuxedo and a white half-cloak over it. As you looked at the man up and down both of you made eye-contact Meeting red cat-like eyes as the man looked at your E/c eyes. That´s when several sharp blades comes from behind the man as you view turns pitch black as you feel pain after a few mins you open your eyes seeing fire around the house as you look at your arm cover in scars as you felt more pain in your limbs and face as Kaburamaru came off of your neck and makes a Noise as he put his head on your forehead. As more fire came around as you look at your hand that was cover in scars as well but When you look at your finger nails they looked different instead of being they way they normaly looked this time they were sharp like you could cut someone skin with your hand as your vison becomes blurry as you Kaburamaru comes around your neck as you lay your head on the ground¨
After the final selection Obanai body was in pain as he walked his way back home as him and his Trainer cross paths ¨Master? what are you doing here?¨ ¨I went shopping for food in another town¨ as Obanai looked at his traner he looked at both sides of him as he gave his trainer a death glare and said ¨Where is my Sister?¨ ¨Oh she´s at home. You know you should´nt worry about her a lot I believe she is older enough to take care of her sister since she´s 13 now right¨ Obanai toke some time to think about it ¨Yeah I guess your right...But if she hurt herself I´m coming after you¨ ¨Hehe Yeah okay come on¨ Both Obanai and his Trainer walked home.
When Obanai runs up the stairs to the trainer´s house excited to see his sister as when Obanai reaches the top of the staircase he see a disturing sight. As he saw his younger sister Y/n on the ground around the burnt ashes of the house and her blood surround her with scars all a as Kaburamaru was around her neck as he gets off and goes to Obanai.
As Obanai stands there looking at his sister as the Trainer makes his way to the top of the staircase and looks at the sight.
¨No, This can´t be happening¨
Obanai drops his stuff as he makes his way to his younger sister as he check her palm as his sister was still alive but heavily injured as he picked her without saying a word to his trainer he run down the stair and head towards the town as he ran though the snow on the way to Mist town as he ran as fast as he could. But as he ran Y/n woke up as she didn´t waste no time to attck Obanai as Catching Obanai by surpie as he tries to lightly dropped his sister on the ground as Y/n still not wasting time and jumped but up and went to bite Obanai neck as Obanai grab a thick stick and hold against his sister´s mouth as Tear of guit and despair drops on Obanai face. ¨If I didn´t went to the final selection you could have still been alive as a human¨ As Obanai was just about to throw the stick and acpeet his death as his trainer shouts ¨It´s okay to hurt a love one cause your doing it to help them¨ As Obanai open his eyes as listening to his trainer´s words he hits his sister on her neck as she passes out.
As Obanai get up his trainer runs up to him and hits him on the neck as both Obanai and his sister were passed out.
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When Obanai woke up. He was in wooden room that was a bed room as he got up and openned the door to greeted by his trainer writing a letter and gave it to the crow and said ¨Give this to Mr.Ubuyashiki and tell him to let the Hashira´s¨. As the crow left and went out to find Mr.Ubuyashiki.
¨Master?¨ As Obanai´s trainer turns to him and spoke ¨If you were wondering I sent a letter to the head of the Demon slayer Corps and told him about the incitdent of you and your sister and said you´ll make sure your sister won´t hurt a human and etc you know, Your sister is in that room also-” With wasting no time Obanai went to his sister´s room and openned the door ¨Y/N!?¨ As his sister turned to him as she had no musul in her month ¨Onii-Chan!¨ as Obanai shut the door behind him as his sister hugs him.
¨Y-Y/n your a demon..Tell me who attcked you¨ ¨Sorry Onii-Chan but I can´t remeber¨ Obanai look on the ground then looked at his sister and hugged her ¨It´s fine Im glad your still here with me¨ as that was the past of the lovey siblings!
As Obanai was now a Serpent Hashira. As he had his own place/house. He asked you if you wanted to stay with him as you say no.
After you made your own path in this world. As you were a traditional japanese dancer. You were the leader of district.{You would know more in the next chaper}.
Your age: 19 Demon years: 6 years
I shall see you all in the next chapter - TsukiTuke
