"Ding! Searching for world!"
"Ding! Matching host's strength!"
"Ding! Matching world!"
"Match successful!"
"Demon Slayer World loading! Loading successful!"
"Loading initial template!"
Mitsuru watched the data fluctuate across his vision, the system interface pulsing with light as it processed. The familiar thrill was already building in his chest. Then the panel paused, displaying his destination.
---
World: Demon Slayer
Level: Tier 7
[A|N : The tier of the world is decided based on the strongest character in the verse, taken from VS Battle Wiki]
Synopsis: A world where man-eating demons plague humanity under the cover of night. The Demon Slayer Corps, a secret organization not recognized by the government, has fought these creatures for centuries using specialized breathing techniques that enhance human capabilities beyond normal limits. At the center of it all stands Muzan Kibutsuji, the progenitor of all demons, and the legendary demon slayers who seek to end his thousand-year reign of terror.
The world operates on a power system built around Total Concentration Breathing—techniques that amplify physical abilities by optimizing oxygen intake and blood flow. The strongest demon slayers, known as Hashira (Pillars), have mastered these techniques to superhuman levels. Demons possess regenerative abilities, inhuman strength, and unique blood demon arts, but are vulnerable to sunlight and Nichirin blades forged from a special ore that absorbs sunlight.
Loaded Character: Mitsuru
Initial Template Assignable Points: 10
Body: 7 (+)
Soul: 15 (+)
Energy: 0 (+)
Available temporary talents are as follows, please choose one:
1. [Best Talent of the Verse] : Your talent is of the highest caliber. You can quickly learn any technique, rapidly achieve mastery, and surpass even your teachers given sufficient time and practice.
2. [Demon King's Body] : You are a newly born Demon King. Your body is immortal, your power is extraordinary, and your blood can turn other humans into demons.
3. [Swordmaster]: Your swordsmanship is supernaturally gifted. From the start, you will be at the peak of swordsmanship in this verse, matching the strongest blade masters.
---
"Demon Slayer, huh?" Mitsuru couldn't help the grin spreading across his face. "Well, at least now I won't have to worry about zombies when I get back. And there's a lot I can learn here."
He absently ran his hand along the katana leaning against his leg, his mind already racing through possibilities.
"Demon Slayer primarily focuses on Breathing Methods," he muttered, thinking through what he remembered from the anime. "They use breathing to amplify the body, supplementing physical capabilities. If that's the case, then maximizing my Body stats should cover most of what I need."
The gamer part of his brain screamed to distribute points evenly, maintain balance, play it safe. But this wasn't a game where he could respawn after death. This was real, and playing it safe had never been his style anyway.
"Allocate 8 points to Body and 2 to Energy."
The numbers shifted.
Body: 15 (+)
Soul: 15 (+)
Energy: 2 (+)
Seeing those balanced 15s made him feel oddly satisfied, and the small energy pool might help with learning breathing techniques faster—at least, that was his theory. His current Soul stat should be more than sufficient for advanced techniques like Transparent World or the Mark. Not to mention he'd have a temporary talent to compensate for any weaknesses. With this extreme allocation strategy, he should be able to maximize his gains.
Now for the temporary talent.
[Demon King's Body] was immediately off the table. Sure, it was practically a "win" button—he could theoretically fight Muzan to a stalemate, a clash where neither could kill the other. The classic solution, if you can't beat them then be them. But he'd be limited to nighttime activities, and even if the system somehow protected him from sunlight, there was still the Demon Slayer Corps to consider. They'd hunt him relentlessly, and he didn't need that headache.
More importantly, it would yield exactly zero benefits after leaving Demon Slayer, since temporary talents disappeared upon world departure. What was the point of immortality if it only lasted for one adventure?
[Swordmaster] was tempting—incredibly tempting. It would instantly catapult him to this world's combat ceiling, essentially making him the new Yoriichi Tsugikuni. One-shotting demons left and right, being an absolute badass from day one.
But it was too narrow, too specialized. He wanted to learn more than just swordsmanship from this world. There were poison techniques, ninja skills—hell, Uzui Tengen was a full-blown ninja. If this were a world like Akame ga Kill, he would have taken it and focused on collecting Teigus.
Besides, where was the fun in starting at the peak? Half the thrill was in the climb, in pushing himself to the edge and clawing his way higher. He wanted to feel that rush again.
[Best Talent of the Verse] was the clear winner. It would let him master swordsmanship at an accelerated pace, learn multiple Breathing Styles, acquire techniques like Transparent World, and pick up skills completely unrelated to combat. The versatility was perfect for someone who needed to prepare for an increasingly chaotic home world.
His main world already had dragons, potential zombies, and who knew what else lurking in the shadows. Future enemies would require a diverse skill set, not just excellence in one area.
Decision made, Mitsuru stood and moved to his closet, digging through for something more appropriate than a hoodie and tracksuit. He couldn't exactly show up in a world inspired by Taisho-era Japan looking like a modern high schooler. After some searching, he found an old hakama and gi from a cultural festival—not perfect, but it would do. He changed quickly, securing his katana at his side.
He gathered his supplies one more time: the backpack with food and essentials, the katana, a few other tools that might prove useful. Everything was ready.
"System, I choose [Best Talent of the Verse]."
"Selection complete! Beginning world hopping!"
"10, 9, 8..."
Mitsuru took one last look at his room—at the photo of him and Akane, at his normal life that he'd return to in the same instant he left. He felt a moment of trance, his surroundings gradually consumed by white light.
Then his vision went black.
---
When Mitsuru opened his eyes again, he was standing in a forest.
Lush greenery surrounded him on all sides, trees towering overhead. The lingering glow of the setting sun cast long shadows on the ground, filtering through the canopy in golden rays. In the distance, he could see faint wisps of smoke rising.
The first thing he noticed was his body. It felt... different. Better. He flexed his hands, rolled his shoulders, stretched his arms. The muscles were more defined, the movements more fluid. His body had been toned before from all his crazy training, but now it felt optimized, like a machine fine-tuned to peak efficiency.
Then he felt it—something ethereal flowing through him like a second bloodstream. Energy. He couldn't control it yet, had no idea how to actually use it, but he could sense it circulating through his muscles, his bones, his very cells. Each place it touched seemed to strengthen incrementally.
"So that's what two points in Energy feels like," he murmured.
Then he looked down and cursed. His backpack was gone. The supplies, the food, everything except the clothes on his back and the—wait. He patted his side. No katana either.
"Seriously? I can't bring anything with me?" He sighed, running a hand through his hair. "Great. No inventory system either. I'll need to figure out a storage solution fast."
Well, no use complaining about it. Time to adapt.
"Let's head toward the smoke. Should be a village. I need to figure out where and when in the timeline I've appeared."
Mitsuru started walking, testing his new body's limits as he went. His stride was longer, his balance perfect, his stamina seemingly endless. The two points in Energy were already paying dividends—he could feel his body slowly, continuously adapting and strengthening even as he walked.
Soon, he approached the village. It wasn't large, maybe a dozen households scattered around a central area. Mostly elderly people, children, and women going about their evening routines. The men were probably still out in the fields.
He spotted a middle-aged man splitting firewood in front of his house and decided to approach. The man looked up warily as Mitsuru drew near—understandable, given he was a stranger arriving at sunset.
"Excuse me, sir," Mitsuru called out. "I'm sorry to bother you, but I was traveling to the city with my family and got separated. Could you tell me where this is?"
The man's expression softened slightly, though he remained cautious. He set down his axe and pointed in two different directions, muttering as he did.
"You youngsters, always so careless these days. Listen carefully—further in that direction is the famous Entertainment District. That way leads to the county town. How'd you manage to get this lost, boy?"
Entertainment District.
Mitsuru's mind immediately went into overdrive. The Entertainment District meant Tengen Uzui's arc. Upper Rank Six. Daki and Gyutaro. That was well into the series timeline, after the Mugen Train arc where Rengoku...
He couldn't help the bewildered expression that crossed his face—half genuine shock, half strategic performance.
'I just arrived and I'm already in the middle of a major arc? What happened to starting with the Final Selection at Mount Fujikasane? No stop! I'm thinking too much, maybe I'm just near Entertainment district that's all,'
The man seemed to take his expression as simple confusion and embarrassment. He sighed, shaking his head like he'd seen this too many times before, and waved his hand in a gesture that was both welcoming and resigned.
"There's been a lot of lost travelers lately. Listen, it's getting dark, and the wilderness isn't safe at night. You can stay here tonight, get your bearings. My wife will make extra for dinner."
"I couldn't possibly impose—"
"Nonsense. In the house next door lives someone named Frieren, and she's always bringing home strays too. We're used to it around here."
Frieren. Frieren.
A bead of cold sweat appeared on Mitsuru's forehead. The immortal elf mage from a completely different anime was living _next door_? In the Demon Slayer world?
What kind of insane crossover chaos was this? If Frieren the Slayer was here, would there even be any demons left for the Demon Slayer Corps to slay? Could Muzan even survive in a world where beings like her existed?
He wanted to ask a thousand questions but forced himself to stay quiet. Maybe it was just a dumb cliche. The sun was setting fast. The man was right—night in demon-infested territory was dangerous, especially for someone without a weapon.
"Thank you so much for your kindness," Mitsuru said with a respectful bow. "I'm deeply grateful."
"Don't mention it. Come on, let's get you inside."
Mitsuru followed the man into the house. The dwelling was a typical Japanese rural home from the Taisho era—wooden construction, sliding doors, modest but well-maintained. Inside, he was greeted by two little girls and a woman, presumably the man's daughters and wife.
"We have a guest for dinner," the man announced. "This young man got separated from his family."
"Oh, you poor thing!" The wife immediately bustled over, maternal concern evident in her expression. "Are you hurt? When did you last eat?"
"I'm fine, thank you. I ate this morning." That was technically true, though "this morning" had been in a different universe that too in night.
The two little girls peeked at him curiously from behind their mother. They looked to be about six and eight years old, with bright eyes and round faces. Seeing them reminded him of Akane.
He smiled at them gently, and the younger one giggled before hiding again.
As the wife went to prepare extra food, Mitsuru's gaze fell upon a katana hanging on the wall. It was old, clearly not maintained for actual use, but the craftsmanship was evident even from a distance. A family heirloom, probably.
The man noticed his interest and grunted. "Don't let the rural setting fool you. My ancestors were samurai, proper ones. That blade's been hanging there for generations now, though. Hasn't seen use in decades. Just a decoration at this point."
"Sir..." Mitsuru turned to face him directly. "Would you consider selling me that blade when I leave tomorrow? I can trade for it."
He reached into his pockets and pulled out everything of value he had—A old style watch and luckily he was smart enough to bring some taisho era coins with him. He held them all out to the man.
The man's eyes widened. "That's... those are clearly valuable items. What's a young man like you doing wanting an old sword? This is dangerous business, boy."
"Sir, I've been separated from my family in unfamiliar territory. The roads aren't safe, and I need something for self-defense. Please—I wouldn't ask if it wasn't important."
The man studied him for a long moment, weighing his words. Finally, he nodded slowly. "Alright. You can take the blade tomorrow morning."
"Thank you. Truly."
Mitsuru was led to a small guest room with a futon already laid out. As he set down his few possessions, he couldn't help but think about how smoothly things had gone. He'd arrived, immediately found shelter, secured a weapon, and got near a key location all within an hour of arrival.
"Maybe high Soul stats affect luck?" he mused. "Or maybe the system does give you a 'starting village' advantage. Wonder if I'll wake up tomorrow to someone saying 'Hey, you, you're finally awake.'"
He chuckled at his own joke, then sobered. Luck or not, he needed to stay sharp.
During dinner with the family, Mitsuru carefully steered conversation toward recent events, trying to gather more information without seeming too curious. The wife was happy to chat, and between her gossip and the man's grumbling about "youth problems," Mitsuru pieced together the timeline.
"Such a tragedy, that train incident," the wife said, shaking her head. "They say it hit a log on the track, luckily there was no causality."
"Terrible business." The man took a swig of tea. "I knew those new-fangled trains weren't reliable. Give me a good horse any day."
The Mugen Train incident. Rengoku's death. That placed him firmly after that arc. Since the incident was recent news he should have three month in minimum before Tanjiro and others came to entertainment district. That should give him plenty of time to try some things.
It's a pity he couldn't stop a victim of donut treatment but he have to manage.
Later that night, Mitsuru lay on the futon, but sleep wouldn't come. Not from anxiety—from excitement. His body was practically humming with energy.
He used the time productively, carefully testing his enhanced physique. He could feel the energy flowing through his body. Every cycle seemed to strengthen his muscles incrementally, even without conscious effort.
"The two points in Energy were definitely the right call," he thought, flexing his hand and watching the play of muscle beneath skin. "Even without knowing how to use Breathing Styles yet, I can feel myself getting stronger. This is like passive experience gain."
He spent the night alternating between meditation and careful physical tests—how high could he jump, how fast could he move, how much could he lift using just the guest room's furniture. Each test revealed capabilities well beyond what his old body could achieve.
By the time dawn broke, painting the sky in shades of pink and gold, Mitsuru hadn't slept at all. But he felt energized, ready. His new body apparently didn't tire as easily as his old one.
A light mist hung over the village as he emerged from the house. The man was already up, preparing for the day's work, and he retrieved the katana from the wall when he saw Mitsuru.
"You sure about this, boy?" he asked one more time. "The path you're walking seems dangerous."
"I'm sure." Mitsuru bowed deeply. "Thank you for your hospitality. Your family's kindness won't be forgotten."
He handed over all the valuables he'd offered the night before. The man accepted them with a nod and passed him the katana. It was heavier than modern practice blades, with real weight and balance meant for actual combat. Not a Nichirin blade, but it would serve until he could obtain one.
As Mitsuru secured the sword at his waist, the two little girls ran out to see him off.
"Bye, Mister!" The younger one waved enthusiastically. "Stay safe!"
"Come back and visit if you can!" the older one added. "And bring more of those chocolate!"
the previous night he couldn't help but spoil them a little as they reminded him of Akane.
Mitsuru couldn't help but laugh. "I'll try. You two stay safe too, alright? Listen to your parents."
He waved goodbye as he left the village, the family watching from their doorway.
As he walked, Mitsuru began experimenting with his breathing. He tried different patterns, different rhythms, paying attention to how each one affected his body.
'What the first generation of demon slayers could do, I can do too,' he thought, feeling that thrill of challenge rising. 'They developed Breathing Styles from scratch, adapted them to their needs. With [Best Talent of the Verse], I should be able to learn by observation and experimentation both.'
Of course, the fastest method would be to find someone actually using a Breathing Style and learn from them directly. But even without that, he could feel progress happening.
After an hour of walking, he reached a small train station. The Mugen Train incident clearly hadn't stopped rail service—people still needed to travel, and life went on despite the dangers.
Mitsuru approached the ticket counter, suddenly realizing a problem. "I gave away all my money last night."
The clerk looked at him expectantly. "Destination?"
"Ah..." Mitsuru glanced at the katana at his side, then made a split-second decision. He removed the watch he'd kept (The man saying it won't be necessary) and placed it on the counter. "I need passage near the Entertainment District. Will this cover it?"
The clerk examined it carefully, then nodded. "This will more than cover it, young man. I can give you change."
"Okay," Mitsuru said. It's better to get some money or else he would face the same problem after reaching Entertainment district.
As he boarded the train—moving carefully past the other passengers, all of whom gave the sword-carrying young man a wide berth—Mitsuru felt that familiar anticipation building to a crescendo.
His first real test in another world. Demons, Breathing Styles, potentially fighting alongside Tanjiro and his gang.
And somewhere in the Entertainment District, Upper Rank Six waited.
Mitsuru smiled, that reckless grin that meant he was about to do something dangerous and stupid.
"Entertainment District, here I come."