Kimetsu no Yaiba x Oc! Reader [SLOW UPDATES]

Prologue

3rd POV

Somewhere hidden deep in the woods, there lived a very special family that had gone into hiding from the demon lord/progenitor, Muzan Kibutsuji, when one of his underlings discovered that the mother had the sacred flower called the Blue Spider Lily. The parents, Kiyo and Masaru Takashi, aren't present at the moment because of their duties, but their three children named Kurt, Mayumi, and Shiro Takashi are living in the mansion that was hidden away by a magic barrier surrounding it.

The oldest of the three, Kuro Takashi, is the only sibling that helps out their parents in an unknown world where angels and devils live. "Hey sis, can you watch Shiro for me, because dad needs help with... somethings," Kuro said to Mayumi. "Sure just don't go destroying anything with your father," Mayumi said, not looking up from her book with her pet dragon sleeping on her lap. Right as Kuro was going to leave, a portal appears making both siblings look in its direction where their mother came out holding a sleeping child. "Mayumi. I have a task for you to do while you stay here on Earth" their mother stated as she hands over a sleeping Shiro to the middle child. "Of course mother, but why must I stay here with Shiro? Why can't I go with Onii-chan?" Mayumi says to her mother as her older brother walks through the portal. "Your father has requested that Kuro should help him with his work and find a soon-to-be wife later on when he is ready" stated the mother. "Also, the task that I need you to do is to help a group of slayers called the 'Demon Slayer Corps' in defeating the demon progenitor named Muzan Kibutsuji, because he is causing too many human deaths to happen." Mayumi thought about it for a bit before answering her mother, "Of course I'll help the Demon Slayer Corps, but they need to prove themselves that they need me to help them kill Kibutsuji." The mother was pleased with her daughter's answer and turned to walk back through the portal before saying, "Of course dear, but I do hope that you will open up to them and find someone that will be your partner until the end." Then the portal that opened up to Earth has disappeared.

Mayumi's POV

I looked away from where my mother had left to do her duties to my sleeping little sister in my arms and thought about what mother had told me. "I will protect you dear sister and that you will have a better childhood than what I had growing up. But the real question is...

Will I be able to trust these humans in the Demon Slayer Corps, defeat Muzan Kibutsuji, and find true love or will my past make me regret trusting humans, helping these slayers defeat Kibutsuji, and true love that I never had?" I switched my gaze from Shiro sleeping in my arms to looking up at the stars in the night sky and thought, "I can only watch from afar to see if these humans are trustworthy.... Only fate can run its course from here."

Family POV

"I do hope that the Demon Slayer Corps can earn our daughter's trust.." the mother says to her husband and eldest son. Both son and father couldn't say much, but the only thing in common that the entire family minus Mayumi thought was...

"please help Mayumi look away from her past and help her restore something that has been missing.

For she is missing her freedom to express how she truly feels and have others to rely on..."

Taisho Secret

Author-chan had originally planned the story out before pursuing to write it out

The family breathing technique is very special that only they can wield (no human can learn it)

Mayumi's breathing technique is special that only she can wield (you will have to figure out what her main breathing technique is with some hidden clues to help you)

Author~chan didn't come up with the different styles for her main breathing technique yet

I will eventually add more details about my OC Mayumi. Yes, my OC may seem a bit op, but it will be interesting to see how things will play out. I'm sorry in advance that the updates will be slow, because I need time to plan out what to write for the next chapter and with school happening. Ara~ Sayonara minna~san! 

-Miyu~chan