(Year 1912)

In a village that was being covered in snow and night sky, a young man was walking down the road with a hood covering his head with a black and gold yukata hearing some people whispering about him but he ignored their words as he then bumped into someone. "My apologies," He apologized to the person and walked passed them before they put their hand on his shoulder.

"Oi, you dirtied my yukata," A man said as he looked over at him and then down at his outfit, "I apologized, what more do you want?" He asked as the man gripped his shoulder. "I want you to clean my yukata," The man said as the young man sighed before gripping his hand and squeezed hearing something pop as the man fell on his knees and yelled out in pain. 

"Now you have a broken wrist to go with your dirty yukata," He said before turning his head and walked away as people went over to help the man.

(Later)

The young man walked up a hill as he looked around, "There should be a hut around here," He mumbled to himself before finding it as he walked up and knocked on the door as a man with a blue haori with white clouds and a tengu mask looked down at him. "What do you want?" He asked as the young man took off his hood and kneeled down. "My name is Kuroi Novachrono, I wish to become your student." He said as the man looked at him before shutting the door.

"No." He said as Kuroi immediately stood up, "What do you mean no?! I traveled miles to try and meet you!" He said as the man opened the door again, "And you can travel miles back home." He said and shut the door as Kuroi clenched his fists before taking a deep breath and calmed down. "I was told that you're the best teacher to train people," He said.

"Whoever told you that lied to you, I don't train anymore and I especially don't train demons." The man said while Kuroi's eyes widen a bit before closing them. "I see, I apologize for wasting your time." He said and bowed before fixing his hood and walked away. The man heard him walk away before opening the door, "What are your reasons for wanting to become a demon slayer. You're killing your own kind" The man said as Kuroi turned around and looked at him with his now slit dark orange eyes, "I don't associate myself with those people. They destroyed my village, killed my friends, and my parents in front of me."

The man looked into his eyes before nodding, "My name is Sakonji Urokodaki, but you will refer to me as Mr. Urokodaki, and from this day forth I am your trainer." The now named Urokodaki said as Kuroi blinked before smiling and bowed, "Thank you Mr. Urokodaki."

(Days later)

Kuroi was seen running through the forest dodging traps that Urokodaki had set up as he stopped and began to pant a bit from exhaustion, 'This man is trying to kill me!' He thought to himself before he sensed something and rolled out of the way from a flying log, "This isn't training, this is hell!" He yelled out before continuing to run and dodge traps.

(Urokodaki's Hut)

A young man with reddish-black hair wearing a green and black plaid haori and a barrel on his back was seen talking with Urokodaki before looking over his shoulder seeing Kuroi behind him with his dark orange eyes that held anger, "Are you trying to kill me?!" He yelled out as Urokodaki turned around. "I was testing your reflexes and it seems you made it back in one piece."

Kuroi clenched his fists before noticing the boy behind Urokodaki, "And who's that?" He asked as the boy stepped forward and bowed. "My name is Tanjiro Kamado pleased to meet you," Tanjiro said as Kuroi took a deep breath and bowed back, "Kuroi Novachrono." He said before looking over at Urokodaki, "When is it going to be day?" He asked him, "A couple of hours, Tanjiro here is also going to be my student." Urokodaki said as Kuroi let out a hmph "Good luck," He said before walking into the hut to lay down.

"Where did he come from?" Tanjiro asked him, "He told me he traveled miles to meet me and the only thing I can say about him, is that he is probably the demon who wanted to become a demon slayer." He said as Tanjiro's eyes widened a bit, "He's a demon?" He asked as Urokodaki nodded. "I could sense the demon energy from him when he first appeared here." He said as Tanjiro looked at the hut.

(Inside)

Kuroi took off his haori and stretched a bit as he sat down before feeling eyes on him as he turned around and saw a girl with long black hair that was dyed orange at the tips with a black haori and pink kimono and pink eyes while having a bamboo muzzle on her mouth with her head tilted.

"I'm guessing your with that Tanjiro kid?" He asked her as she crawled over to him and got close to his face which made him back up a bit before sensing something off about her, "Your like me aren't you?" He asked again seeing her pupils become slits as his did as well. "Demon blood got in your system?" She nodded as Kuroi chuckled, "Same with me" He said before rubbing her head seeing her nuzzle into his palm which made him smile a bit.

"What's your name? I'm Kuroi Novachrono" He introduced himself as she tilted her head before Tanjiro walked in and kneeled down, "Her name is Nezuko. I'm trying to help her become human again," He said as Kuroi looked over at him. "I'm not sure that's possible but if so then good luck on your journey." He said as Tanjiro smiled before grabbing his hand with both hands. "When we're done training, please come with us" He asked as Kuroi looked at Nezuko seeing her nod.

"Well, seems that our lives are gonna get more interesting," He joked as Tanjiro chuckled a bit and nodded. "Is Mr.Urokodaki's training hard?" Kuroi looked at him, "It's not training, it's hell." He said as Tanjiro thought he was joking before seeing he was serious. "Oh, well it can't be that bad." Kuroi chuckled a bit, 'Tanjiro, you just jinxed yourself.' He thought before blowing out the candle and went to sleep.