Demon Slayer Swap AU

Chapter 5: Nezuko's Journal, Part 2

"Where'd you come from?!" Nezuko shouted.

"What are you doing?" The girl asked, tilting her head to the side slightly.

"Doing? I'm training." Nezuko responded, still sitting on the ground.

"How long do you plan to have your ass stuck in the mud. Come on, take a stance!" The girl said, her expression hidden behind her fox mask.

Nezuko did as she was told, getting up to her feet and taking a fighting stance.

"Now.. attack!" The girl said.

"But.. I have a wooden sword, and I gave a real one!"

The girl giggled, "Oh, don't worry about me! Rest assured, I'll be fine!" The girl then rushed towards Nezuko, clashing her sword against Nezuko's. "You can't hurt me! I'm rather strong! I've already split a boulder! Thanks for worrying, though!"

"You split a boulder?!" Nezuko exclaimed, rather shocked by that fact.

The girl nodded as Nezuko was knocked to the ground. "Of course! The breathing technique taught by my father! Total Concentration Breathing! You just memorised it as a fact, but your body needs to understand it!"

Her father? Does she mean Keizo? Is he her father? Nezuko wondered as she got up to her feet.

"You need to bear it into your flesh and blood! More, and more, and more! So that you become the embodiment of the secrets Father taught you! You need to beat it into the marrow of your bones!" The girl exclaimed, swinging her sword at Nezuko with immense speed.

"I do! I do, every day! As hard as I can! But no matter how hard I try.. I can't progress any further!" Nezuko shouted, trying her best to fodge the girl's hits.

"You can't just try! You need to do it! Show me your strength! What have you got? Show me!" The girl shouted, but then hitting Nezuko hard enough to knock him out.

....

When Nezuko came to, she was lying on the ground, with the girl leaning over her. Her mask was now on the side of her head, and Nezuko could now clearly see the girl's large, rounded tear-filled pink eyes with flower-shaped white pupils.

"Are you alright?!" The girl asked frantically. "I'm sorry! I went too hard on you!"

Nezuko sat up, not really minding nor caring that she'd just knocked her out. If anything, she felt admiration towards the girl.

"That was an incredible blow! Not a bit of unnecessary motion! It was truly beautiful!" Nezuko exclaimed, making the girl's eyes widen slightly at her sudden compliments. "That's how I want to be too! But is that even possible? Can I do it..?"

The girl then smiled softly, her tears evaporating. "I'm sure you can. I'll help you!"

"Uh... who are you?" Nezuko asked, staring at the girl's warm smile. She was rather cute.

She says her name is Koyuki. Koyuki points out the defects in my style. She corrects my unnecessary movements and bad habits. Why is she doing this for me? Where did she come from? I ask, but she never tells me.

"I really like my father."

She often says those words. Apparently, Keizo is her father, and he raised her and some other boy she never told me the name of. She spoke rather fondly of him, though.

"There are other children too. They're all around, watching you." Koyuki had once said.

Koyuki is a bit of a strange girl. She says things in a weird way.

"Total Concentration Breathing accelerates your blood flow and heartbeat. And your temperature shoots up." Koyuki explained. "You're still human, but you get strong like a demon. You expand your lungs, and bring lots of air into your blood. Your blood gets excited and your bones and muscles thrill. You get hot and strong!"

I don't really get it.. how can that be? Nezuko wondered as she listened to Koyuki's words.

"You must train so hard you could die. Basically, I don't think there's anything else you can do." Koyuki said.

I swing my sword so hard that it felt like my arms and legs would come off, and that my lungs and heart would burst in my chest, but I still couldn't beat Koyuki.

Another six months passed, until one day, when I went to face Koyuki, she held a real sword.

"After half a year, I think you're ready now. You look stronger." Koyuki said, drawing her sword as she covered her face with her fox mask

"Today, I will win." Nezuko said confidently.

The contest was simple. The stronger, faster blade wins. The fight was over in an instant.

That day, in that moment, for the first time, my blade reached Koyuki first, and slashed her mask in two.

When I won, Koyuki smiled. It seemed like a sad smile to me, or maybe proud and reassuring.

"Win, Nezuko.. against them, too."

Suddenly, Koyuki disappeared, and I found that my sword had not cut Koyuki's mask. It had split the boulder.

Word Count: 830