Kokushibo stood on the roof, his six eyes watching the endless river of death below. Zombies, both normal and mutated, were all moving together like a dark tide towards the human camp. It was a terrifying sight, but to him, it was just background noise. His mind was stuck on those bottles of blood.
He had gained so much Muzan's Blood from them. It was a huge amount, more than he got from hunting for nights. But what made that blood so special? It smelled like the mutated zombies.
Thinking of Ariya, he remembered how strong she had gotten. It had only been a few weeks, but she was much more powerful. How many people had she eaten to get that strong so fast?
Then his thoughts went to a part. When he turned her into a demon, he saw her memories. That wasn't supposed to happen. From what he knew, Muzan could only see a demon's memories when they were about to die. So how did he see Ariya's past while she was still new and alive?
He remembered her memories clearly. Her father had injected her with a strange virus long before the apocalypse. Her body couldn't handle it. The virus made her blind, erased her memory, and put her in a coma.
When he found her, a zombie was eating her stomach. She should have been dead from those wounds. Any normal human would have died. But she was still clinging to life. It wasn't just her potential or will to live. He realizedt it was the virus. The same virus that broke her was also keeping her alive all those years.
When he turned her into a demon, he was able to see the memories of the girl who was lost.
But this made him think of her sisters. They were different from normal too. He remembered something from that night.
Flashback
Right before he killed them, Kokushibo noticed their bodies were acting strange. He used his Transparent World to look closer.
Deep inside their bodies, he could see the virus. It was different kind of virus that was in Ariya when she's "human". And this virus was reacting to the blood from the smashed bottles. It was like the blood or the contents of the bottle was calling to the virus inside them.
At that moment, he also sensed Ariya nearby. She was leaking killing intent. He was impressed she could already do that after just a few weeks. She had improved a lot.
Looking at the two sisters shaking and the virus going crazy inside them, he understood. These girls were already dead in a way. The virus was what kept them moving and thinking. They were like a special kind of mutated zombie.
"I guess these girls won't survive tonight even if I let them live," he thought. "Ariya would probably kill them."
He decided to test his theory. If they were a new kind of mutant.
After he killed them with his sword, his system notified him. [ABSORPTION PROTOCOL AVAILABLE]. He was right. His guess was correct. The two sisters were a type of mutated zombie, different from the others.
Then he sensed Ariya again. He could feel she was staring at her sisters' dead bodies. Was she... drooling? The girl was actually drooling over her own sisters' corpses.
"I guess this girl is a real food lover," he thought with some amusement.
Flashback End
Now, standing on the roof, it all made more sense. The special contents in the bottles was connected to this virus. The virus that Ariya and her sisters had was different from the normal zombie virus. It was stronger, and it reacted to the bottles.
It was pure, concentrated version of whatever this special virus was. And that's why it attracted all the mutants.
He looked toward the camp again. With all those mutants gathered there, drawn by the scent of that bottle's blood, it would be a perfect hunting ground for him. He could absorb many of them and grow his power even more.
The system screen appeared in his vision.
[KOKUSHIBO TEMPLATE: 100% SYNCHRONIZATION]
[NEW TEMPLATE DOWNLOADING: 88.9%]
[MUZAN'S BLOOD: .40.1%]
The progress was still slow, but with so many mutants gathered in one place, he could speed it up.
He also wondered about Ariya. Was she heading to the camp too? Probably. She might already be there.
He gripped his flesh katana. Without another thought, he stepped off the building and began moving toward the camp, his six eyes glowing in the dark. The hunt was on, and this time, the prey had gathered themselves in one place for him.
---
Dr. Crenil sat in his lab. He was thinking about the bottles. The ones the two girls stole. A small smile was on his face. Everything was going how he wanted.
He had let the girls steal the bottles on purpose. He knew they would take them. He left the door unlocked. He made sure the guards were not looking. It was all his plan.
He had lied to General Roberts. He told the General the bottles had special blood from mutated zombies. He said it was for finding a cure. That was not true.
The real truth was... those bottles is special. A trigger. The two girls, Kaily and Xxya, already had a virus inside them. He gave that virus to their father, his friend Klov, years ago. He told Klov it was medicine to make his sick daughter strong.
It was a lie.
The virus did not make them strong. It broke them. It made Ariya blind and put her in a coma. It made Kaily and Xxya crazy and violent. It was a failure.
But this new serum in the bottles… this was different. It was made to wake up the sleeping virus inside the two girls. If they drank it, or if it got in their blood, it would change them. It would turn them into real monsters. Not just crazy zombies. True mutated zombies. That was what he wanted now.
Flashback – Five Years Ago
Dr. Crenil was not always like this. He had a son. His name was Eli. Eli was a good boy, but he was sick. His body was weak and frail. He got sick very often. Because of this, the other kids at school bullied him. They called him names. They pushed him. They took his things.
Dr. Crenil worked long hours. He was a scientist for a big company. He was not home much. He did not see how sad and depressed his son was.
One day, he came home early. He found Eli in his room. Eli had killed himself.
Dr. Crenil broke. His heart shattered. He went to the police. He wanted the boys who bullied Eli to be punished. But the boys were all underage. Their parents were rich. Nothing happened to them. They did not go to jail. They did not even say sorry.
Dr. Crenil's sadness turned to anger. Then his anger turned to hate. He hated the bullies. He hated their parents. He hated the world that let this happen.
He was a scientist. He decided to use his skills. He would make a serum. A virus. Something that could make a weak body strong. Make it powerful. Make it aggressive. So no one could ever bully again. He would fix the weak.
But he needed to test it. He could not test it on himself. It was too dangerous. He needed someone else.
He remembered his old friend, Klov. Klov also worked in science. Klov had a daughter. Her name was Ariya. She was born very sick. Her body was weak. She was frail, just like Eli.
Dr. Crenil went to Klov. He lied. He said their company had made a new serum. He said it could cure weak bodies. Make them strong and healthy. He said it was a miracle.
Klov did not believe him at first. It sounded too good to be true. But Dr. Crenil kept asking. He kept lying. He said it would save Ariya. After many weeks, Klov finally agreed. He was desperate to help his daughter.
Dr. Crenil gave Klov the first virus. Klov injected it into Ariya.
It was a disaster. Ariya's body could not handle the virus. It was too strong. her body couldn't adapt to it. It made her blind and erased her memories. It put her into a deep coma.
Klov was furious. He yelled at Dr. Crenil. He said he ruined his daughter.
But Dr. Crenil did not stop. He was obsessed. He said it was just the first try. He said he could fix it. He needed to adjust the formula. He asked Klov to let him try again. This time, on the other two daughters, Kaily and Xxya. They were healthier. Maybe their bodies could handle it.
Klov was angry and scared. But he was also a scientist. He wanted to fix his mistake. He wanted to believe a cure was possible. So, he agreed.
Dr. Crenil made a new version of the virus. Klov injected Kaily and Xxya.
This time, it was different. The girls did not go blind. They did not go into a coma. Instead, the virus twisted their minds. It made them angry and violent. A few days after the injection, in a rage, they attacked their own father. They killed and ate him.
Dr. Crenil arrived too late. He saw what happened. He had to clean up the mess.
He knew his creation was a failure. It did not make people strong and safe. It made them into monsters.
His hate grew. He thought of the boys who bullied Eli. They were still out there. Living their lives. Happy.
He found them. There were three of them. They were teenagers now. He kidnapped them. He took them to a secret lab. He injected them with new versions of his virus. He experimented on them. He wanted to see if he could control it.
One of the boys, the one who was the ringleader of the bullies, was stronger than the others. His body fought the virus hard. One night, he broke free and escaped from the lab.
He ran into the middle of the big city. He collapsed in a crowded street. People gathered around him, trying to help.
The boy's body changed. His eyes turned blank. He stood up. He was not human anymore. He attacked the person closest to him. He bit them.
The virus spread. From that one bite, to another, and another. It moved faster than anyone thought possible. Within hours, the city was in chaos. That was when the zombie apocalypse begun.
When the outbreak started, Dr. Crenil was in his lab. He was scared. He saw the news. He knew it was his fault. The virus he made had escaped. It was killing everyone.
He tried to hide. He tried to survive. After a few weeks, he was found by soldiers. General Roberts and his men rescued him. They brought him to their camp.
The General questioned him. Dr. Crenil was a famous scientist. The General asked if he knew about the virus. If he could make a cure.
Dr. Crenil saw a chance. He lied again. He said yes, he could study the virus. He could find a cure. But he needed time. He needed a lab. He needed test subjects.
The General agreed. He gave Dr. Crenil everything. He gave him safety, soldiers to protect him, and captured mutated zombies to experiment on. The General's plan was simple: find the cure, and then control it. Sell it. Be the most powerful man in the new world.
Dr. Crenil's own goal was gone. His dream of making a serum to make the weak strong was dead. His son was dead. The world was dead. He had destroyed it.
Looking at the ruined world, he felt nothing. No sadness. No guilt. Only a cold emptiness. If the world was already destroyed, he thought, why not destroy it even more? Why should anyone get to live in a world that let his son die?
He stopped trying to find a cure. He started a new project. He remembered the first virus he ever made. The one he gave to Klov for Ariya. That virus was different from all the zombies. It slept inside the host. It did not turn people into mindless zombies right away.
That virus was still inside Ariya. And it was inside her sisters, Kaily and Xxya. It was sleeping. What if he could wake it up? Not to make them strong. But to make them perfect destroyers.
He worked day and night in his new lab. He experimented on the captured mutants. He studied their blood. He needed to make a trigger. A key to unlock the sleeping virus in the two girls.
But to make the trigger serum, he needed a special ingredient. A blood that resisted the normal zombie virus. He found it in the camp.
Captain Mark Reynolds had a daughter. She had been bitten early in the outbreak. But she did not turn into a full zombie. Her body fought the virus. It could not fully adapt. She was in a coma, but she was not dead. She was not a zombie. She was immune.
Dr. Crenil took her blood. He told the Captain it was for research to save her. Another lie.
Using her unique immune blood, he finally made it. The trigger serum. He put it in three bottles. It was a red, glowing liquid. It smelled like power. It would call to any zombie. But most importantly, it would scream to the specific, sleeping virus inside Kaily and Xxya.
He just needed to get it to them.
He did not have to wait long. The two girls were in the camp. They were survivors. They hated the soldiers here. Especially Captain Lee, who had hurt them. They were looking for a way to get revenge.
Dr. Crenil made it easy. He let them hear rumors about his special blood samples. He left his lab door open. He watched them sneak in and take the box with the bottles. He did nothing to stop them.
He knew what they would do. They would try to use the bottles to get the six-eyed monster to help them. Ofcourse they would fail. The monster would kill them. But before they died, they would probably drink a bottle. The serum would get on them. It would soak into their skin. It would enter their bodies.
And it would wake up the sleeping virus.
His plan was almost perfect. The two girls would turn into powerful, new kinds of mutants. The General, who was going after them, would be their first meal. The six-eyed mutated zombie that had consciousness would be the second. And the scent of the spilled serum would draw every zombie for miles to this camp.
He looked at the clock. It had been hours since the girls stole the bottles. It was almost time.
He walked to the window of his lab. He could hear the normal sounds of the camp.
Then, he heard it. A low, distant rumble. It was not thunder. It was a sound he knew. The sound of many, many feet. The sound of moaning, growing louder.
He smiled. It was starting.
A young soldier ran into the lab, his face white. "Doctor! Something's wrong at the south wall! The guards are reporting movement!"
Dr. Crenil nodded calmly. "I see."
More noise erupted outside the lab. Shouting. Running. The camp's alarm started to blare—a loud, screeching sound.
BOOM!
An explosion rocked the building. The wall of the lab cracked. Dust fell from the ceiling. The lights flickered.
Dr. Crenil did not move. He just stood by the window.
A huge crash came from the direction of the main gate. The sound of tearing metal. Then, the screams got louder. Closer. They were not just scared screams now. They were pain screams. Dying screams.
He looked out.
Chaos. Pure chaos.
People were running in all directions. Soldiers were trying to form lines, firing their rifles. But the zombies were coming from too many directions. The fences were down in three places. They poured into the camp like a flood.
He saw a normal zombie grab a woman and bite into her neck. He saw a mutated zombie, with long arms, vault over a truck and land on two soldiers. He saw the camp's lights start to go out, one by one, as generators were overrun.
The banquet had begun.
This camp had 6,000 people. Soldiers, families, survivors. In a few hours, they would all be dead. Or they would be part of the horde. This place would be a graveyard.
One of the higher-ups was yelling at his men, trying to organize a retreat. He did not see the dark shape drop from the roof above him.
It was not a normal zombie. It was big. Its skin was tough like leather. It had long, sharp fingers. It was one of the mutants drawn by the bottle's scent.
Dr. Crenil watched.
He turned and went back into his lab. He closed the door. The sounds of the camp being destroyed were muffled now. But he could still hear them.
He sat down at his desk. He looked at a small, framed picture he kept in a drawer. It was a photo of his son, Eli. Smiling. A smile that was gone forever.
"The world that failed you is ending, Eli," he whispered to the photo. "Soon, no one will be left."
He put the picture down. He listened to the screams.
Outside, the horde grew larger. More zombies came, attracted by the noise, the blood, and the last fading scent contents of the bottle. The camp was a beacon of death.
And on the edge of the chaos, unseen by the dying humans, a tall figure with six eyes watched. Kokushibo saw the feast and saw his own opportunity. And high on a broken wall, another figure with white hair and a blindfold watched too, her stomach growling. Ariya had followed the scent as well.
---
Kokushibo stood on the roof of a tall building near the camp. Below him, chaos reigned. The military camp was being destroyed. Zombies and mutated zombies were everywhere. They were killing people, breaking down walls, and eating everything. It was a perfect hunting ground for him. There were so many mutated zombies here, all in one place. He could gain a lot of Muzan's Blood.
He was about to jump down and start hunting. He was about to farm the mutants for power.
But then, something happened.
A blue screen popped up in front of his face. It was his system. It made a loud, alarming sound in his mind that he had never heard before. It immediately grabbed all of his attention.
[NEW TEMPLATE DOWNLOAD COMPLETE]
[INTEGRATION READY]
[WOULD YOU LIKE TO ACTIVATE THE NEW TEMPLATE? YES/NO]
Kokushibo stopped. He was completely still. The noise and chaos below him seemed to fade away. He just stared at the blue words.
The download was finally done. It had taken so long. He had almost forgotten about it.
He focused on the notification. The system showed him the name of the new template. He read it.
And he was shocked.
He knew this template. He knew this character. From his old world, from the animes and mangas. This character is more terrifying than Kokushibo in completely different way.
Without any hesitation, he made his choice.
"Yes," he said.
The change began instantly.
His six golden eyes, the marks of his demonic power, began to fade. Not just change—they vanished. One by one, they closed and disappeared into his skin, as if they had never been there at all. Where six glowing eyes had been, now there was only smooth, unmarked skin.
Next was his hair. His long, dark hair with the blood-red tips lost its shine. It became dull and lifeless.
His clothes melted away. The fine, dark purple kimono and samurai pants dissolved. In their place, new fabric formed. A modern, dark suit appeared on his body. A white dress shirt and a black tie.
Then the real changes started. The changes to his flesh.
In the center of his forehead, the bone began to split. It cracked open cleanly. But no blood came out. Instead, cold, gray steel pushed through. It grew out of his forehead, pointing forward. It was installed into his skull.
From the back of his head, more metal formed. A hammer jutted out, fused to his bone.
His left arm was next. The arm that once held his flesh katana began to harden. The muscles locked and changed shape. They turned into mechanical parts. His fingers fused together. His forearm stretched and elongated. The skin turned to dark metal.
In a few seconds, his entire left arm was gone. In its place was an M4 carbine assault rifle. The barrel, the receiver, the grip—it was all one piece, grown directly from his shoulder. It was now a part of his body.
The transformation finished.
What stood on the rooftop now was something new.
He was tall and wore a sharp black suit. His hair was messy and black, falling over his face. His face was now featureless except for the pistol gun barrel sticking out of his forehead.
His left arm was a fully-formed rifle.
The feeling coming from him was completely changed. The heavy, cold, moonlit terror of Upper Moon One was gone.
Now, the air around him felt colder in a different way.
A blue screen appeared in his vision.
[NEW TEMPLATE TRANSFORMATION WAS COMPLETE]
[THE GUN DEVIL.]
"So this is the gun devil's power" Aki hayakawa said.