Mastery

I was still dazed after passing out on one of the city rooftops. The light piercing the windows was almost blinding.

"Ow" I yelped, after a flick injured my forehead.

"Yes you lost, you stupid kid" Grandpa was right beside my futon, resting on his knees next to me. "You lost because you didn't know any better. So all things considered, you didn't do too bad. Good job" 

"Thanks." I muttered "But who was that?" 

"Luck really isn't on your side, brat. Your first night out you encountered a demon"

"Demon?"

"Yes, a demon. They're a race as ancient of us. The only difference is that their diet consists exclusively of human meat, making them our primary predator"

"Why didn't you tell me this before" I asked

"Shut up I'm not finished" He hissed at the interruption. "Demons are not only stronger and faster than humans, but some of them even possess mysterious abilities."

 I looked at him in confusion 

"Demon strong, no approach because die" He made exaggerated gestures as though he was talking to a deaf person.

"Fuck you old man" I shot back. "I get that, but you just want me to accept that demons are real?" 

"Well they are so get used to it. You'll be tasked with fighting them one day. Besides you can't deny their existence, you came face to face with one." 

"Is that right" I sighed, my eyes fixated on the ceiling

"The demon slayer corps is what takes care of these demons and ensures the safety of citizens" He added. "If putting your life on the line to slay demons to protect people who will never know you even exist sounds like something you want to do, you can join"

"Sounds rough. Do I get paid" 

"Not nearly enough" Gramps snorted

"Sounds fun. How do I get in?" 

"You.. actually want to join?" He stammered out 

"Well yea, not that I'm an altruist who would put his life on the line for other people. But I don't know, I guess it feels like the right thing to do. Plus fighting demons is fun" I replied honestly

"To each their own" He shrugged with a defeated look ok his face

"One more thing before I leave, demons can turn people into demons by feeding them blood. Do not swallow any demon blood or I will personally decapitate you" He got up and headed towards the door. "Oh right I almost forgot, to kill a demon you have to cut it's head off. Well then, I'm off"

'That was crucial information he almost omitted, damn geezer' 

I spent the next few hours in bed. The rest of my family came to visit me together later on in the day. They didn't so much as ask what happened. 

"You weakling, how could you break your arms while training" Tatsuya said with a laugh. 

His remark was met with a slap against the back of the head by both parents. 

'I guess gramps told them a story about how I got injured training. I can read concern all over their faces' 

"Yuuki, are you going to leave like our older sister" Hanabi, my older sister asked 

Her question was met with glares from dad and Tatsuya, my mother's expression hardened at my sister's mention.

"Hanabi" Mother said with a stern tone. "We talked about this"

Hearing my sister's name avoided like the plague sparked my curiosity, but I didn't ask any questions.

"Right now, I'm not going anywhere. I'm going to stay right here" I reassured her

She responded with a soft smile.

The meeting was cut short by servants delivering a message to both my mom and dad about some family business stuff. They had an annoyed look on their faces but looked at me with eyes of regret.

"Yuuki, we're gonna leave now, speak to any of the caretakers if you're feeling any discomfort" My mother said as she caressed my hair.

"Right, see you later" I responded

That left me with my two siblings. I filled Tatsuya in on my training with gramps and discussed with him different sword techniques. Tatsuya brought a wooden sword in to show me some of the stuff he learned from dad which I greatly appreciated, as gramps never taught me anything to do with basic sword fighting. Meanwhile, Hanabi was studying my sword with great admiration. She even attempted to join in on the demonstration, but her skills were, sub par.

When servants came around announcing dinner was ready, both the siblings departed, leaving me alone with my thoughts. Not that I thought, I just fell asleep.

Two days passed and my arms and legs fully healed. I stood up from bed and immediately opened the water breathing manual.

'First order of business, train. Train until it doesn't hurt anymore.'

I performed every move of water breathing with just my sword, getting used to performing the movements with deadly accuracy, something which I'd already done for a year. Then, I activated total concentration and performed each of the movemts at half speed to reduce the pain caused by overusing my muscles.

'This is effectively microdosing on pain. If I get used to it now, not only will my muscles develop in accordance with total concentration, allowing me to perform more moves but it should also increase my pain tolerance. Hopefully. I'm no scientist'

The first months were horrible. I required 2 days of rest for every day of training, greatly increasing the time it took to master learn water breathing. 

After the first two months though, not only did the pain subside, allowing me to take virtually no rest days apart from one day of the week where I would just train total concentration, but my mastery over the sword art improved my leaps and bounds. I was already able to perform every form before, but now I could also minimize any and all wasted movements, making me more efficient. 

There was no concept of birthdays in this world. This meant I had to keep track of my own age, something which I did by keeping track of the change in seasons and whenever winter rolled around, I would add a year onto my age.

By the time the tenth winter of this life rolled around, I had mastered water breathing. Every intricacy of the style completely analyzed and accounted for, every wasted step removed and every swing refined to perfection.

Or so I thought.

"This is it? This is what you wanted to show me?" Grandpa asked raising a brow

"I did what you asked, I mastered water breathing. You said I couldn't do it but I did." 

"True, you might have learned, practiced and refined each form. But thats only the bare minimum. You think the greatest swordsman haven't done what you have one thousand times over? The result you achieved is good, but it can be better. It can always be better.

"For starters, you didn't create any additional form. You can't call yourself a true master until you've taken on the challenge of innovation." He simply stated. "Though, to be honest with you, you have achieved something that is simply impossible to do at your age. Not even some of my best students could have ever dreamed of achieving what you have at such an age

"But are you satisfied with that Yukiko? Are you satisfied with being simply better than everyone? If so, get out of my face and never come back." 

'What the fuck. Now this is just plain unfair. Though he is right, I'm not yet satisfied. I need more' The anger past me would've felt was replaced completely by an insatiable thirst for power. Once I'd gotten a taste for combat, I just couldn't go back.

"No sir!" I shouted 

"Good" He nodded