Demon Slayer: Kimetsu no Yaiba x Reader One shots

Muzan Kibutsuji |Cannot be Replace

Requested by Bloomingknight

Muzan was feared by demons and demon slayers alike, he was supposed to be the strongest demon, he was supposed to be perfect in every aspect, but all it took for him to gave up everything he had achieve was the brightest smile that come from you, a human. 

His knees goes weak whenever you would be within his sight, something about you make his heart thump, a feeling he though he was incapable of doing. 

All it took was those gorgeous eyes to stare at you like he was looking at your own soul to make you fall in love with him. and just like that, two different species fall in love to each other and they live happily ever after-as if. if only it was that simple.

Not a lot of demons agree that the most superior being would be accompanied by a human, that is in their eyes was nothing but food, though they cowards who won't dare questioned Muzan. Muzan find that situation too dangerous for you, so he gently asked for your approval to turned you into a demon. 

and because of love, you agreed, who wouldn't want to spend eternity with their love one, days, weeks, months, and years pass by quickly and you and Muzan receive the best gift ever, you become pregnant.

Knowing you were Pregnant, Muzan's protectiveness increased by thousands, he would not allow you to step out of the mansion at all, he would always asked trusted demons to guard you whenever he was not around, though you understand him, it was boring as hell. 

"I'll be back soon, so behave and wait" Muzan said as he kiss your forehead and leave the room, outside you could feel the presence of  another demon that was supposed to guard you at all time.

"You're bored too right?" you said, talking to your baby as you rub your belly feeling it slightly kick, making you chuckled.

your attention quickly shift to the window, where the moon was high and brightly shining as if inviting you over.

"It wouldn't hurt to get some breath from time to time right?" you grinned as you climbed out the window, easily escaping and jumping down careful not to bump your belly.

"It's been so long since I've been out" you talk to yourself as you wonder throughout the forest surrounding the mansion. 

"this are so pretty " you excitedly said as the flowers got your attention.

 as the moon shine to the flower you admire it so seriously that you didn't notice the eyes of a predator eyeing you.

"you're dead!" you were startled as someone jump from behind you, when you turned around to see it was too late to dodge, so you close your eyes waiting for the pain but instead you felt blood splashing to your face.

When you opened your eyes, you saw your husband's back, as he easily cut off the head of the demon who probably mistaken you for a human.

"tch you scum!" Muzan muttered as he took out some cloth and wipe his hand.

"Mu-chan" you softly called, not sure whether to be happy he save you or to feel guilty because he catch you going outside. you were fidgeting with the hem of your clothes waiting for his lecture, but instead you were engulfed in a warm hug. 

"were you hurt anywhere? I told you not go out without me or anyone" he muttered his hand holding and protecting your head to his chest.

"sorry, are you not mad?" you mumbled,melting on his touch

"How can I get mad at you...I'm just disappointed that you'll go out without informing me" he said as he pick you up bridal style, carrying you back to the mansion.

"neh Mu-chan can I ask you something?" you said as you look up to be met by his plum red eyes.

"you can ask me anything you want to know" he replied 

"..you've been living for so long and I'm sure you've been everywhere, you've pretty much seen everything, I was wondering what among those treasure you've seen had been the most valuable, like some kind of rare diamond or gold or something" you asked curious, Muzan simply chuckled, a sight rare than rarer.

"I've actually found the greatest treasure in this world" he said so proudly

"what really?! can I see it? what does it look like?" you asked your curiosity killing you 

"It was a treasure that no amount of everything I had know would suffice, a treasure that cannot be replace no matter what" he again said as he kick open the door to the room and lay you comfortably on the bed, followed by him after. 

"That seems so important, what is it exactly? I really wanna see" you said getting excited like a child.

"hmmm look over there" he said as he motioned to the mirror attacked to the wall, you turned around only to see your reflection as a hint of realization hit you.

"you're so sweet" you chuckled as you peck him on the lips getting happy at situations like this.

"the both of you..." Muzan said as he place his hand on your belly the baby kicking at his touch. 

"...no one in this world would be able to replace you, no matter what"

"I Love You Muzan for as long as I live"

"I Love You too (Y/N) more that anything" 

(OMAKE)

"But seriously don't leave the mansion without accompany" 

those were his words, and starting that day whenever Muzan was away, one of the upper demons would 'babysit' you whenever you wanted to go outside, your favorite among them was none other than Akaza himself. 

"come one Akaza, can you feel it?" you said excited as you took Akaza's hand and made it touch your belly.

"ohhh amazing it really does kick" Akaza exclaimed surprised by the kick of the baby, Akaza's expression was always the best among the upper demons.

Later on, Muzan would change his mind when he saw you happily smiling and chatting with the upper demons, so he would change your 'babysitter' to Nakime.