KNY | SWAP AU

training

A black bird in the sky was speaking to the former hashira Hairo, who had long ago given up his place to someone else. It had a note on his foot, alongside a pink ribbon that was given by Gyokko

"Greetings, mister Hairo." The note said, "I've sent a young girl who wants to be a demon slayer" The handwriting got almost unintelligible "She was so brave! She challenged me unarmed, nothing but a stick on hand. Her family was killed by a demon." This didn't surprise the man "Her brother was turned into a demon, yet it appears that he won't attack any human." This did surprise him. "The girl has an incredibly good sight, and this just feels different... I hope you're able to train her. Sincerely, Gyokko." Hairo folded the note.

"How do I kill him then?" Nezuko asked.

"Can you not think for yourself? I think it's a stupid question."

Nezuko didn't know what to do, she didn't want to hurt the demon even if it killed multiple people. Then, the sun started raising and the demon slowly faded away, eventually dying.

While Hairo gave the dead a burial, Nezuko went to check on Tanjiro, who was safe in the basket she made. Then, she went out.

"My name is Hairo" The taller man said, Nezuko just noticed how he was wearing a mask. "I assume you're the ones Gyokko told me about?"

The girl nodded, assuming Gyokko was the slayer she met. "I-I'm Nezuko! And my brother's name is Tanjiro"

"Nezuko. What will you do if your brother eats a human?"

Before she could finish processing the question, she was slapped.

"You're too slow when it comes to decisions. You didn't kill that demon before daylight." The man spoke, some anger could be found on his voice. "If your brother ever ate a human you'd have to do two things: one, kill him, and two, slit your own throat." She knew he was totally serious about this, and that she'd have to accept her fate if anything like that ever happened.

"You must acknowledge that this is something that mustn't happen. Do not let you brother take an innocent life, do you understand me?" Hairo's voice got even more serious.

"YES!!" Nezuko accidentally screamed.

"Well then..." A small pause "I will now proceed to test you to see if you have what it takes to be a demon slayer. Bring your brother and come with me." And just like that, they all started running.

Nezuko tried to keep up with his speed, but it was impossible. She was panting and sweating like crazy, she never ran that fast before. Heck, how old was this man?! How did he make his steps so quiet?!

They finally stopped, Nezuko was wheezing and panting. "D-did I pass the test?" She said, exhausted.

"The test starts now. Hike the mountain." The face she made must've been funny.

Hah. Hah. Nezuko could only breathe through her mouth. Her legs hurt and she didn't feel her feet.

"Now, your goal is to get to my house which is at the end of the mountain. This time I will not wait until dawn."

Wow. That sounded easy, the fog was heavy but she could see a lot better than normal people, so to her it was almost invisible.

What she didn't know was how many traps there were at the mountain. She fell in the first ones, getting hit by rocks, a tree and falling, but she quickly learned how to dodge them, even though she would still get hit by some of them.

The door creaked as she opened it, her face, arms and legs bloody from all those traps.

The door creaked as she opened Hairo's door, "Hah... Hah... I've made it back... Like I promised..."

"I recognize your abilities... Kamado Nezuko."

"I am a cultivator" Hairo explained to Nezuko what he did. "I cultivate swordsmen and prepare them for the 'final selection', I also get to decide who goes and who doesn't."

Nezuko's stamina and sight increased a lot, as she went back and forth through the mountain with traps. She also trained sword swinging and realized how weak the swords were, getting snapped really easily. Nezuko also learned how strong Hairo was in a wrassling match against him.

She also started training breathings and their forms. He taught her the breathing that he used, called Shadow Breathing. This one really came handy when fighting demons, it was really strong, specially for her since she didn't really know how to fully use it yet.

Tanjiro had been asleep for half a year, which really worried Nezuko. She wondered if he could die just like that, but she didn't have enough time to think.

She practiced in places with little oxygen and more dangerous, she wondered if she could die right there.

"I don't have anything more to teach you." Hairo said that after a year of training. "You can train on you own. Your objective is to slit this rock in half to prove yourself. I taught you the basics, now it's your time to improve them and make your own style if you want. If you're able to break the rock then I'll let you enter the final selection."

The rock was taller than her. How would she be able to break that?

She continued to practice every day, she was thankful she wrote some trainings down, it made the whole thing easier.

Half a year later she started to doubt herself. She'd been training for so long, could she even do it? Was all of her training not enough?

She kicked the rock "I NEED TO WORK HARDER!! HARDER!!!"

"SHUT IT!!" A voice spoke from the top of the rock. "You're just screaming nonsense."

When did he appear? She didn't see him before. A fox mask on his face.

"No matter how difficult and painful this might be, if you're really a woman you have to shut your mouth and deal with it."

The guy then started floating and attacked Nezuko, but she blocked his attack with her own katana. He kicked her to the ground.

"Slow, weak, rusty, you're definitely not ready to be a slayer." The masked man stood before her, was he even human? Maybe he was a beast or a monster. She couldn't figure it out, but she definitely would.