Nobody pov
The year is 2030, and life has grown to a point of no return. Humans have learned to live their lives to the fullest in the Sun while being ignorant of what lies in the shadows
Waiting to feast. We move on to a boy running down the slums of the city with a small child on his back
Y/n:(breathing heavily) I'll save you, ... I promise
He trips but gets back up trying to move a faster
Y/n: don't die on me, Nina!
Two days earlier
In front of an orphanage, a boy gets ready to leave while dressed in a construction uniform
???: already heading out y/n
An old woman dressed in a nun outfit
Y/n: yeah gotta leave early or ill be late
Nun: you know y/n you don't have to do this, the city already gives us money
Y/n: yeah but it's never enough, and they like to skip payments they promised so it's better I do the work anyway
Nun:(sigh) Well I can't argue with that
Y/n: it's fine Granny, if I can help I'll help
Nun: what a little saint you are
Then three little kids ran up to y/n before he could leave the church doors
Mina: hey y/n are you leaving for the city
Troy: we wanna come too!
Nun: no you're not, you're staying right here. The cars broke down so he can't take you
Mina: but we wanna go!
Troy: we can help
Y/n: you guys help enough, this kinda work is for the biggest in the house and that's me. But don't worry I'll play with you guys all night when I get back okay
Troy: you mean it!?
Mina: promise!
Y/n: promise
Y/n then looked up to the slightly older boy standing behind the two young kids
Y/n: hey make you look after everyone while im gonna knucklehead
Mike: yeah I know that you don't gotta tell me
Y/n: awe, look at you. Such a big boy~
Mike:(blushes) Stop that!
Troy: look he's blushing
Mina: knuckleheads red like a tomato
Mike: I am not!
They all laugh as y/n walks past the kids waving
Y/n: alright im off
He leaves the orphanage but not before running into two girls
Mia: leaving so soon
Y/n: gotta leave early to be on time
Nina: I got a new dress, play with me
Y/n: when I get back I promise
Mia: get going if you stay any longer you probably gonna be late
Y/n: your right im off!
He said running past the two
Time skip
Y/n made it to the construction site just barely as he was holding his knees while breathing in and out heavily trying to catch his breath
Y/n: boss...im here!
???: oh they're you are kid
???: your a little early don't ya think
Y/n: gotta make a little extra money, so I need the hours
Boss: well im not stopping ya, start over there we need those bricks broken and taken to the dump
Y/n: im on it
???¹: y/n! Help me!
A man said running up to him holding prices of broken glass
Boss: ugh you again
???¹: help me out boss said she'd take away some of my pay because of this you gotta help me! Do that star wars thing you do!
Y/n: ugh, it's not. You know what never mind
Y/n placed a hand over the shattered window glass and felt the presence of a
Y/n: this was done by a group of dogs
Boss: huh, really now
???¹: see I wasn't the one who did it
Boss: but weren't you in charge of locking up last night
???:...
Boss: your pay is docked
???¹: NOOOOOOOOO!!!!!!!
the man screamed as he lost all the color in his boys
Y/n:( Sorry dude, but you learn )
Time skip
Boss: alright boys that's good enough for today
Everyone: YES MA'AM!
Y/n was about to walk home when someone put a hand on his shoulder and it was his boss
Boss: you're not gonna walk home at this time right
Y/n: yeah it's not that far back home so I should be good
Boss: no shot, not with the curfew, get a hotel for the night my friend's got a place just tell him I sent you
Y/n: it's cool I got star wars powers
Boss: don't argue, you need to stay off the streets at night, or else the demons will show up
Y/n: s-sure
Time skip
The sun shined and y/n was needed leaving a hotel as a man waved him goodbye
Y/n: thanks for the room
???: no problem just tell ya boss she owes me
Y/n: you got it!
Y/n started to run back to the orphanage after a long day of work
Time skip
Y/n:( Those brats are gonna jump All over me for not playing with them.)
Walking up to the orphanage y/n saw the door to the church was wide open
Y/n: did they leave the door open all ni-
He stops and breaks out in a sweat, as his body starts to shake he starts feeling the sensation of the reaper scythe on his throat
Y/n: tch!
Despite being so scared he ran into the church only to see a blood train with Mina laying on the ground holding onto Nina
Y/n: Nina!
He ran up to the two girls but tripped on something and when he looked down his eyes widened and his breath became scarce
Seeing the rest of the kids and the nun's body parts scattered along the ground he wanted to scream but all he could do was breathe faster and faster hearing only hearing the sound of his heart race in his chest
Nina:(coughing)
Y/n:!!!
Y/n looked over to see Nina's hand move ever so slightly
Y/n:... Nina
Present time
Y/n was running down the streets of the city trying to make it to the nearest hospital but none of them were open as the curfew came nobody was out. Just him
Y/n:(somebody, please! Please help my sister!)
Nina started to wake up as her body began to move and her hair turned blue
Y/n: Nina?
She violently shook y/n off and fell off his back
Y/n: shit, hey Ni...na
Nina got back up without a problem not saying a word as her appearance had completely changed from what y/n knew. And as he looks on he gets a feeling in his right arm like it was missing or someone bit it off
Nina:(growling)
Y/n: N...Nina
Nina then rushed y/n as he moved but fell on the ground narrowly avoiding her as Nina tried to take a bit out of him
Y/n:( did..did she try to)
He was cut from his tough as Nina tried to devour him but y/n grabbed her by the throat and lifted his leg to push back against her body
Y/n:( What the hell is going on! Is this what the boss was talking about did nina become a demon, No that can't be right she could have taken any opportunity to eat us when we slept but she didn't!)
Suddenly Nina's body began to grow bigger and bigger making it harder to push her back as y/n continued to struggle to hold her
Y/n:( And now her body's getting bigger there's no doubt, she's become a demon. But how do I save her how do I stop this how do I save her!?)
Unknown to y/n a man in black jeans and a white t-shirt was running along the rooftops
Y/n: Nina, im here! I won't leave you alone again. I promise! Just come back to your senses
Y/n didn't feel any resistance from Nina who suddenly stop struggling as and was crying
Y/n: hey there lil sis i-
Y/n saw a man with green hair about to stab Nina as she saw this too but y/n then rolled over to protect his sister the green hair man saw them and avoided hitting y/n barely but scratching his arm
???: tch, it's gonna be one of those nights huh?
The man stood up and puts his katana back in its scabbard while also snatching Nina away from y/n as y/n looked at his hands noticing she was gone before looking up and seeing the green hair man
???: you know I could have killed you right?
Y/n: Give my sister back!
???: hmm, you mean this demon?
Y/n: she's not a demon!
Y/n stoot up only for the man to pull his Satan out and rest its blade on Nina's throat
Y/n: Nina!
???: stay right there brat
Y/n:...
???: if you didn't know, I'm part of the Demon Slayer Corps meaning I have to decapitate your sister to keep the peace
Y/n: wait, she hasn't killed anyone she's just-
???: what a demon? Maybe she didn't kill anybody and maybe she won't. But I will not be the one to take that chance
He said resting his blade on her neck as it started to run her
Y/n: please! Don't Kill her! (crying) Please don't kill my sister...she's all I have left
???: and what would make me stop
Y/n:!?
???: this world isn't run by weak people and their words of sadness it's run by the strong and those who have strength cut down anything in their way.
Y/n:...
???: I will kill your sister, and there is nothing you can do, sorry kid
The green-haired man stabbed Nina in the shoulder as she screamed in pain
Y/n: Stop it!!!
Y/n threw a random rock at the man but he easily blocked it before seeing y/n charge at him
???: letting your emotions control your actions, it's pathetic.
As soon as y/n got close the green-haired man went to cut him down but y/n dodged the strike before his blade landed
???:(he dodged that, no it was like he knew where I was going to strike before I even moved)
Y/n then punched the man in the face as a counterattack only to make the man angrier as he kicked y/n in the stomach causing him to pass out
???: (this brat, it's like his body moved on its own, sensing the danger and avoiding it)
Nina stopped and starred at y/n on the ground passed out from the kick, she grits her teeth and kicks the green-haired man away before rushing to y/n
???: crap! She'll kill him!
But to his surprise, she didn't instead his eyes widened seeing Nina standing over him on all fours growling at the green-haired man
???:...( I don't know how many times I've seen it, families being torn apart by their blood.)
Nina started to rush him as the green-haired man began to avoid her strikes with ease
???:( when a demon is starving it'll stop at nothing to kill a human and devour its body. This one's different she could have easily killed him but instead she chose to protect him)
Nina then jumped in the air and went to strike the green-haired only for him to back up while putting his sword away
???: (maybe these too are...)
He then got behind Nina and knocked her out with the scabbard of his katana
Time skip
Y/n suddenly woke up and the first thing he saw was his little sister still alive and breathing
???: hey brat
Y/n hearing that voice got up quickly and stood in front of Nina
???: your sister is fine since it's dark still she'll live. But don't let her anywhere near sunlight got it
Y/n:...
???:if you want revenge for your family and really want to help your sister, go to the Grand Shasta, and look for a man Hispanic man name Dracula Mihawk. Tell him Roronoa Zoro sent you. Also, try to do something about those horns of hers
The man vanished leaving y/n alone with his sister
Time skip
Outside the orphanage y/n and Nina stood in front of five tombstones. The graves of their family members
Y/n:... let's go, Nina
She nodded her head and the two walk away to find the man at the Grand Shasta
_____________________________________________