[Seiji's POV]
(Flashback)
"pLeasE KilL mE!!!~"
The pieces of flesh trembled and vibrated to create the sound of a scream.
"kiLL mEEEEEEE!!!!~"
"I haven't quite found it yet," I said to the demon, "Please try to survive until sunrise."
After I learned the basis for my new technique, I began experimenting. I already discovered the Demon's key, which allowed me to easily cut demon flesh or anything made from demon cells.
But that doesn't matter since a demon could regenerate almost infinitely during a fight. I could cut them again and again, but it won't matter if I cannot inflict lasting wounds like a Nichirin blade could.
I travelled all across Japan, experimenting with my new techniques on the demons. I was not just slaughtering them anymore, I was torturing them in the name of innovation and I didn't feel sorry at all.
I would cut them up for as long as they could regenerate and leave them to die by sunrise. Even when I finally figured out, I still used then as training dummies.
I think I've lost part of my humanity as well during my journey, the part that could empathise with another living being. Demons were a danger to humanity, most of them were an enemy.
But there were also victims among the demons like Nezuko in the canon or Rengoku, but I couldn't feel sorry for them anymore. I didn't hesitate to slay a demon just because of them.
I've turned myself into the bane of demons. I became their sole executioner.
The next technique I created only affirmed my status as annihilator of demons. I became the ultimate Demon Slayer.
"Frequency of Death," I named the technique.
I could create a vibration on my sword so precise and lethal that when I cut demons, they could no longer regenerate. I mutilated their existence with each cut inflicted.
It was the next evolution of the Demon's key.
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*BOOOOOOOM!!!!!!*
The world of Demon Slayer did not scale high in terms of raw power compared to other fictional worlds.
But when two pinnacles clash, even the mountain has to give respect and buckle under the weight of the clash.
Well, it was mostly Kokushibo who was responsible for the catastrophe. Meanwhile, I was only responsible for splitting the forest horizontally. I was faster than destruction, so while the environment suffered, I was unharmed behind Kokushibo.
"Phaaaaa~" I released a huge breath, and my body ached at the sheer strain of the technique.
I saw the cracks on my sword before I branded it to the side. The blade was masterfully crafted with the best quality, but it was not meant to persist under the pressure of precise vibrations.
It had lasted me for so long, I wouldn't complain even if it broke now.
My arm felt numb as well. My body had partially adapted to my new form, and I could maintain the frequency of vibration, but it was still yet to be perfected.
In the meantime, I turned around and gazed at the back of Kokushibo.
He remained frozen in place, his back turned on me. The raw destruction in front of him was slowly settling. The world hung in broken strings in front of him.
"You know, it's quite rude to turn your back on your opponent," I said while standing still.
In truth, I would love to take advantage of his opening and launch another attack but my body was frozen from the strain.
He slowly turned to me but even then his eyes never looked at me. All six orbs were focused on the place where he used to have a hand. His wrist released a copious amount of blood but strangely enough, he was not regenerating.
"What did you do to me?" he asked and finally looked at me. He held out his hand as if to show me.
A flicker of smoke came off as he healed his injury. But his hand never came back, it remained a stump. His arm ended at his wrist like it were its perfect natural state.
I smiled seeing that the technique also worked on a demon of his calibre. I was almost certain it would work but demons were supernatural beings and could always pull bullshit out of their ass.
"Try as you might, but you will never grow your hand again. After all, your own body is convinced that it has healed perfectly," I said.
His eyes glowed red, infinitely curious, "What do you mean?"
I contemplated whether I should answer his question or not. I was not the villain, so explaining the nature of my technique to the enemy was not my job.
At the same time, the fight between us was more like a battle between two warriors than a human and a demon. In the end, I decided to entertain his curiosity,
"I don't know if you keep up with modern science, but basically, every living being, be it demons or humans, are made of cells. And these cells listen to something for instructions." I began my explanation.
I discovered the technique before I realised how it works. After I had invented the frequency of death, I went to the city and studied to learn how it works.
"Mechanotransduction. It's a new term that humans discovered recently. It simply means that cells can change their behaviour based on physical forces like tension or vibrations."
Kokushibo tilted his head, clearly he did not know what I was talking about. All those science terms were unknown to him, heck he didn't even know what cells were.
I continued anyway and made it easier this time.
"Fighting is a conversation to me. Actions are words. I did not simply cut off your hand, I convinced your body through physical language. I tell your body, 'This is how you should be,' and they believe it," I said.
Kokushibo stayed silent but there was more understanding in his eyes this time. He nodded curtly, as if to pay respect.
"A fearsome technique," he said.
"Well, it's only the first method," I said and then the faint mark on my forehead glowed bright and expanded.
All this time, I hadn't activated my Demon Slayer Mark and when I did, the change was immediate. The wind that blew at me paused before they ran away and changed direction.
Not just outside but internally, my perception of the situation changed. When filled with such power, it changed my whole mentality.
A beat of silence.
A pause of realization.
"Here's the thing Kokushibo," I said while taking a rigid stance. I felt unimaginable power coursing through my body. It had been a year since I activated my mark so it almost felt overwhelming.
"As much as I wanted this to be a great battle, I can no longer cling to a delusion. I don't think I'll ever have a real battle again. This fight has truly opened my eyes since I considered you my greatest opponent," I said while taking in huge volumes of air.
A small hurricane came alive around me.
"This war is over. The rest is just... ceremony."
Kokushibo burst out fast. He was a lightning wrapped in fury. My words cut deep into his heart, partly because he knew I was telling the truth. His attack was him testing my words.
So he gave his best.
"Moon Breathing: Sixteenth Form!!!"
The night exploded and darkness was torn away by sheer destruction.
"Moon-Dragon Ringtail,"
My eyes flashed purple as I beheld the might of the attack. Ones, tens, hundreds, no thousands upon thousands of crescent blades bloomed from his sword. They spiralled outward like demonic halos.
Each slash bent space, cutting through stone, wind, and even light. They curled, twisted, and collided in a storm of lunatic destruction. The world itself seemed to fracture under the barrage.
For a moment, darkness was chased away by the light of these energy blades and everything the light touched ceased to exist. Dust rose, trees screamed, the air bled silver.
In that moment, regret swallowed my heart. I wished I could fight this. I wished I could win against this.
But I was forced to cut them away and disregard them with one casual swing. As if the power in front of me was not a masterpiece refined over centuries of dedication and sacrifice.
It's like a game of chess. My opponent played beautifully, without flaw, without making a single mistake. But unfortunately, I've figured out I could just kill the player without playing the limited pieces.
I disappeared. I was already one of the fastest beings in the world one year ago. I could contend with Kokushibo in terms of speed even during the first fight where I was injured.
But after learning flashsteps and activating my mark, I was simply too fast for any attack to hit.
"Demon Slaying Art: First Method,"
Only now did I realize how cold the style I invented was. It did not even try to fight the demons, it just ends them with the ultimate efficiency.
My eyes saw the vibrations in the air, I saw the patterns in the attack and I created an imaginary path which was void of disruption. It was an opening.
I followed that path at lightning speed. The world turned black and white, as if light itself was now struggling to catch up to my speed. For the first time, my speed matched my perception of time.
Even before he realized, I sliced off his leg in one casual swing. I blurred past him and went around the area to turn. My eyes locked on his form as he buckled. His leg healed quickly but never regrew the limb.
His leg now ends at his knee.
He moved.
But I moved master.
I blurred past him again, this time I took his arm. His sword fell on the ground and after he healed his injury, his arm stopped at his elbow.
I went around the area again to attack him from another direction. This time I took his other arm. When he healed he was left armless. With the vibration on my sword, I convinced his body, I mutilated his existence.
Again and again. I blurred past a dozen times until my body protested and told me to stop.
And so I did. I stopped in front of him.
But by that point my opponent lay in pieces.
...
...
"I'm sorry," I apologized sincerely.
In a way, I had disappointed him, just in a different way. I was not too weak, I was too strong.
Demon Slaying Arts had seven forms, seven methods.
Against the strongest demon in existence, six remained unspoken.
...
...
[IMAGE]
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Author : That's it for the fight. Thanks for sticking so far.