Muzan's Little Sister. (Yandere kny x child reader)

░▒▓█Very Late Christmas Special █▓▒░

(A/N : This is kinda a filler chapter so you can skip it (๑•́ ₃ •̀๑) this face reminds me of Haganezuka- anyway, I am going to explain this chapter cause it's kinda confusing oh and I am going to spoil a little bit of Chapter 6, but don't worry not everything that is going to happen in here is going to happen there.)

 (Explanation : After the trial, Shinobu offered to take you to the butterfly mansion because she may or may have not injected some poison into your leg by accident, she feels kind of bad about it but anyway, you are staying in the butterfly mansion to recover, there you met Inosuke, Nezuko, Tanjiro, Zenitsu, Aoi, The butterfly girls, and Kanao, you also stayed with Rui because he was injured too, (I know demons can recover easily but its wisteria poison ╭( ･ㅂ･)و) now Christmas has come and you are planning on celebrating it with your new family. *ଘ(੭*ˊᵕˋ)੭* ੈ✩‧₊˚)

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                                              '*•.¸♡ Y/N'S POV ♡¸.•*'

I opened my eyes and the first thing that came into my mind was 'Today is Christmas!!! I'm so excited!'(I almost put exited-)I got out out of the hospital bed and saw it was night time, 'Phew,' I thought. I guess they at least already decorated a little bit, hmm? I walked down the hall and saw that they put some Christmas decorations around such as a mistletoe, pine cones, some artificial grass, cranberries, etc. It looks so pretty~ I can feel my eyes light up in excitement.

                                           '*•.¸♡ No One's POV♡¸.•*'

The h/c haired demon was jumping around in excitement, she didn't notice the people behind her, until she felt her tiny frame get picked up from behind by... "Nezuko-chan!!" said Y/N cheerfully, very happy to see her sister-like demon friend "Hmph! hmph?? <3" said Nezuko, (Translation : Hi, Y/N-Chan! How are you?) you just gave her a thumbs up meaning you are doing fine. You looked behind her seeing your other sibling-like friends, Tanjiro, Inosuke, and Zenitsu. 

You waved your hand at them, making Nezuko a little jelly, so to get back the attention on her, she suddenly hugged you tighter making you flinch and Nezuko started running down the hall to the front door leaving the three males behind.

Nezuko exited the mansion and went outside, only to be greeted by a lot of Christmas decorations, exaggerating amounts of snow, a snowman, a Christmas tree, and a beautiful sky.

Both of your eyes lit up at the amazing view, suddenly you heard a lot of voices coming from behind you "LOOKS VERY FLAMBOYANT IN MY OPINION!" "UMAI!" Woah...FIGHT ME!" "What was the snowman's name again?" "Ara Ara~ be careful not to bite your tongue while eating!" "*muffled* THIS IS DELICIOUS!" "Itadakimasu" "Mitsuri, you're speaking with your mouth full" "INOSUKE DON'T EAT THAT!" "YOU STUPID BOAR LET THE SNOWMAN ALONE!" "Please, let me eat in peace you little insect" "Nee-san Shinobu, you okay?" "INOSUKE! LET THAT SNOWMAN ALONE!" "Tanjirooo-kun!!!" multiple people said, the small h/c haired demon let out a gasp of excitement, everyone's head turned to look at her. 

"Moshi Moshi N/N (Nickname)~ Merry Christmas!" said Shinobu "Merry Christmas to everyone!" you screamed, very excited. "I got you all presents! <33" you said, everyone's eyes widen "Such flamboyant little girl" "AWE YOU DIDN'T HAVE TO YOU CUTIE <3" "*muffled* UMAI! VERY FLAMBOYANT INDEED" "Y/N you didn't have to, but thank you!" "Such a pure child" "Hmph Hmph Hmmmmppppphhhhhhh!!!" "N/N AWE YOU DEMONLY CUTIE!" "Thank you" "Thank you" "*CRIES* THANK YOU Y/N-CHANNNNNNNNNN" "ZENITSU GET OFF OF HER! Also thank you Y/N" "HAHA THANK YOU M/N (MISPRONUONCED NAME)" "*flips coin but stops it in midair* Arigato Y/N-Chan..." "Thank you little cloud" the red eyed child had to cover her ears because there were a lot of screams. She proceeded to go into the Butterfly Mansion and take all the gifts, she gave the gifts to everyone and they opened it, they were beyond happy, they couldn't stop thank her.

After they calmed down, they began eating, until Tanjiro suddenly sniffed the air and dropped his chopsticks on the food, he grabbed his Nichirin Blade that was conveniently in his belt and ran off, by the look of the others faces, (Teriffied) something bad was going to happen or was unfolding. 

You tried to sense any presences nearby that could've alert them, and well well well who do we got here? Six new powerful presences nearby. Y/N's eyes widen, she recognized this people- or well demons. It was Uppermoon 1, 2, 3, 6 and Lowermoon 5, so that's why you couldn't find Rui...

Y/N quickly got up and started following the Hashira and the kamaboko squad while the non-slayers stayed behind. You caught up to them and started running along side them looking for your demon friends.

You all came to a stop and found who you suspected, Kokushibou, Douma, Akaza, Gyutaro, Daki, and Rui. You felt somebody's aura getting terribly mad, you quickly turned your head to see Shinobu with a pained but at the same time mad expression on her face "Y-YOU! YOU KILLED MY SISTER!" Shinobu yelled and pointed her blade at Douma, you gasped, you didn't know Douma had killed her sister. Douma gasped "I'm sorry my dear but I don't care about who you are or who is your sister, I have better things to worry about right now sweetheart! Like Y/N!" Douma said, ignoring Shinobu's shouts and threats, you hugged her to calm her down and once you did her eyes widen "Y/N, are you friends with this demon?" Shinobu asked, ignoring the fighting going on between the demons and the slayers.

"Yes, he is Douma-oni!" Y/N replied, Shinobu nodded and glared at Douma that was fighting with Kanao, Inosuke, Mitsuri, and Giyuu, Douma seemed to noticed the glare and only smiled back, almost putting the middle finger to Shinobu if it wasn't for the fact that Y/N was there. So he did the only thing any demon would do, attack her. Shinobu was a bit surprised but fought back.

Y/N was started to get pissed, and some people noticed because of the aura or vibe she was giving. She could feel her brows furrow in anger, her nails growing, she was clutching her hand in a fist and she screamed "STOP IT RIGHT NOW EVERYONE! TODAY IS CHRISTMAS SO WHETER YOU LIKE IT OR NOT WE ARE GOING TO CELEBRATE IT TOGETHER!" everyone was surprised and scared, so they complied, they also complied because of how yandere everyone is.

Right now everyone is eating together, humans with demons. Surprising, huh? The demons were in the right side of the table and the humans in the left side, you were sandwiched in between Daki and Nezuko, both having a staring contest and growling at eachother. You decided to ignore them and eat your food.

Time passed and it was already 11:55, only a few minutes left till it's officially Christmas. You were all gathered at a special place you found some time ago, it was near a town.

You knew something very wonderful was about to happen so you gathered everyone at a mountain near the town. You waited a few more minutes, it was 11:59 now "What exactly are we waiting for?" asked Daki, saying what everyone else was thinking "Yeah...what are we...exactly waiting...for?" said Kokushibou, in his normal monotone voice, as if on cue, you could see the sky light up with fireworks and now it was officially Christmas.

"MERRY CHRISTMAS!" Y/N screamed.

A/N : 

Merry Late Christmas and Happy New Years guys! Sorry I haven't been updating much, so, I made this very long chapter of 1230 words or more! Hope you enjoyed, bye! >:3 Sorry for any grammar mistakes! Please point them out ~