Disclaimer: Kimetsu No Yaiba (Demon Slayer) and its characters don't belong to me. I just use them to manage my boredom.

Chapter 1: A cruel world... With a twist

Nezuko had been having a bad feeling since she woke up that day and she doesn't understand this uneasy feeling but something tells her something bad is going to happen.

She was helping her mother dry the clothes close to the fire since there was snow outside and it could freeze their clothes. Meanwhile Tanjiro and her other brother were looking for logs for the fire. Her mother left a couple of minutes ago to finish their lunch so Nezuko was left alone with her thoughts.

After she finished their lunch was ready so the five kids and their mother walked in to eat. The feeling remains even when nothing happens all day. Then Tanjiro spoke "Mom, I will go to the town to sell coal"

"No, please..." she whispered softly and all of them looked at her.

"Nezuko... are you alright?" asked her mother, reaching to touch her older daughter looking so some fever or something physical that explains what was happening with her.

"I...I just have a bad feeling... mom..." her mother smiled kindly at her.

"Tanjiro, do you want her to go with you? I'm sure if she goes she will help you and she will feel better, right darling" Nezuko nodded softly and Tanjiro smiled.

"Of course mom" he said and stood up then pat his sister's head "let's go Nezuko"

Takeo said "Aww... I can't ever go with my big brother and Nezuko will go first?" he pouted looking at his mother.

"Maybe next time Takeo, ok?" said their mother with her usual kind and sweet voice, the young boy nodded still pouting.

When they were ready, both Kamado siblings left their house and went down the mountain. They were talking and laughing at Takeo, fighting to go with them.

When they arrived to the village, people started to approach Tanjiro asking for his help as usual. Smell this, smell that, help me find something or let my mom clear I didn't stole her homemade cookies.

Nezuko also helped with some other stuff while her brother was busy, then their usual clients bought them coal until they ran out of it. Tanjiro promised to return tomorrow with more.

The couple of siblings headed back to their home, it was late afternoon so the sun was setting already. Tanjiro and Nezuko passed by a house at the beginning of the mountain.

"Oh Tanjiro, Nezuko. Are you going back home?" They nodded with a kind smile on their faces "I would like to recommend you to not travel by night. It's quite dangerous, there are demons at night"

Tanjiro looked confused and rubbed his head "we will be ok sir"

"Please, I'm begging you..." Said the old man, his eyes seemed to be filled with tears.

Tanjiro looked at Nezuko and she nodded softly then she looked at him "sure, we will stay" the man's face lighted up and let them walk in.

He made them food, prepared two futon beds for them and kept the fire up.

They ate and talked about their day, the man asked about their mother and siblings. They told him about their earlier fight with their other brother and he laughed.

Then they went to sleep. This time Nezuko had a nightmare. She was arriving home the next morning, there was blood around their dining room and her siblings room. Their mother lying on the floor, dead like her other siblings, Tanjiro was next to her crying and looking around with an ax. He kept looking for a bear or a pack of wolves, but there was nothing to be found.

She woke up sweating and screaming. Tanjiro was by her side "oh... Thank God... You weren't waking up and I was getting worried" he hugged her tightly with some tears.

"Tanjiro, we should go back home... I... I want to make sure... Everything is ok..." He nodded. They had a light breakfast because the old man forced them to and left that house.

Nezuko was walking quicker than Tanjiro. He was getting worried but he kept her rhythm. They arrived in record time but the scenes before them weren't the one they were expecting.

Like in her nightmare, her mother was dead on the floor, their siblings were in their room, dead. Blood everywhere and none of them were alive. Tanjiro was desperately looking for an animal but there wasn't any, not even a blood tray to look for.

Nezuko started to cry out loud, making Tanjiro run back with her and hugged her. They were crying when a young man in his nineteens arrived. He was wearing black clothes covered by a two-sided haori, one half was dark red and the other had a green and yellow pattern of triangles.

He walked to them, placed his knees on the snow and his cold eyes softened at them "hey... I'm Giyuu Tomioka. I...I'm a demon slayer..." He said a little hesitating about that last part "I got a report from this location... About a demon close by... I...I guess I wasn't quick enough" Tanjiro looked at him, he could tell by his smell that he was telling the truth and he could notice the guilt in his words.

Even when he understood he was hurt "yeah... You are... My... My mom and siblings are gone..." His red eyes full of tears, Giyuu's heart skips a beat, he couldn't get there in time, he couldn't save someone again.

"I'm sorry..." He said feeling sick with his own weakness.

Tanjiro and Nezuko realized he was dealing with a huge guilt so the girl said "we weren't here either, we couldn't help them either..." Her pink eyes were full of tears.

"We should go inside. It's cold here" they nodded.

Giyuu helped the Kamado siblings clean the house and buried their family. They prayed for them and got in the house. They drank tea in silence.

"Do you want revenge?" He asked them. Both kids nodded "then join the demon slayers corp. I will train you to wield a sword and to fight demons" he said looking at them. His blue eyes seemed lifeless but when he asked them to let him train them, they seemed alive again.

Tanjiro and Nezuko nodded after a full minute of thinking.

"Perfect. Let's go to my house. From now on, you are my students" and with that the Kamado siblings left their home and headed to Giyuu's to become demon slayers and avenge their family.

OOooOOooOO

I wrote this after I watched a video about this what if. Let me know if you liked it and want me to continue it.

Hope you liked it.