[Multiverse]Voyage Through The Worlds: Starting with Demon Slayer

Hello everyone, before we start I would like to clarify this story will be posted on both Wattpad and Fanfiction

"Person speaking"

"Person thinking"

"Other Entity speech"

"Other Entity thoughts"

"Attacks"

If you read on sites without Bold, Italic, or Underline available

"Person/Entity speaking"

'Person/Entity thinking'

[{Chapter Start}]

The ex-Water Hashira said nothing, taking off his sword and placing it on the table. He then knelt down, giving me a bowl of soup. Dazed, I took the bowl. He handed me some chopsticks and a spoon as he took off the logs on his back, adding them to a small fireplace and using them to heat up the room high up in the mountains.

I said nothing as I watched Urokodaki do his daily chores. I sipped on my bowl of soup without chopsticks or spoons, uncaring for my image. All I needed right now was some food. However, most Anime teachers usually have some super-hidden testing method, so just in case, I memorized everything he did, burning the orders and methods in my brain.

Once I finished the bowl of soup, Urokodaki picked it up, setting it aside. He then sat in front of me, addressing me directly.

"What is your name boy?" Jeez, I know the anime portrayed him as a strict person, but this intensity is something else in real life

"My name is very long; you can just call me AYD." A moment after saying that I cringed. Was that the right thing to do? Should I have just told him my real name?

'I'm still socially awkward huh' I thought with dismay as I clenched my fists.'If only I was normal'

"Very well, AYD. I washed the clothes you were wearing earlier. I've never seen such fine stitching before, and the material—it's of much higher quality than what we're used to around here. I can't help but wonder... are you a noble, or perhaps someone of high status?"

I blinked at the question, caught off guard. High quality? To me, it was just basic denim. But I guess, given the era, what I considered normal could be seen as luxurious here. This wasn't some time period where denim was even a common fabric, let alone the quality of mine. Not to mention, I had the appearance of someone healthier than most, less worn down by the rough life of the average person here.

"I'm not a noble, but I can be called a person of high status" I'm a member of UA High, and I think that at least brings up my status somehow right? God, I sound like those Harvard students boasting about their college.

"I see, then I must ask what someone of your status is doing in a remote location like Mt. Sagiri, and why you were extremely malnourished when I found you unconscious"

"I-I come from a faraway land. My friends and teachers were attacked and they nearly died. I heard there is a method to make me stronger, and I heard you were one of the few people who could help me" I'm impressed by myself, somehow lying despite everything I said being the truth, I wasn't aware I could do something like that.

"Heard of me? I'm not sure who you heard about me from, not many people in this era know of me." Urokodaki said, closely scrutinizing my face. "I'm not sure why you're lying, are you a spy sent by the emperor so he can monopolize breathing techniques in his army? If that is so, then tell him the Demon Slayer Corps have already refused, and our techniques will not be used to kill humans"

The emperor? Oh, the current emperor of Japan, I forgot Japan wasn't always a Democracy. Still, weren't Demon Slayers not recognized by the emperor as an official organization? I always thought the emperor was just unaware of demons, but it looks like that wasn't the case.

'It does make sense, a person ruling over the entirety of Japan should be aware of the existence of demons and the slayer corps. Still, the Slayer Corps must be immensely powerful if they can refuse someone like the Emperor'

Nevertheless, that's not what I care about right now.

"No, no, you've got it all wrong," I said, raising my hands defensively. "I don't work for the Emperor, nor do I care for his goals. I only seek strength—nothing more, nothing less. Strength to protect the ones I care about. There's no hidden agenda, no ulterior motive. Just that."

"Hm, and where exactly do these friends of yours live?" Urokodaki asked, his voice calm yet firm, as if testing the truth behind my words.

"They… live really far away, not in Japan," I said, glancing down at my bowl. "You saw my clothes, right? They're American. I've traveled a long way to learn your techniques." My voice held steady, but inside, I prayed he'd believe me.

Urokodaki sighed, shaking his head. "What you are saying will only make a normal person distrust you even further."

I bit my cheek, frustration boiling inside me. Was I seriously going to miss out on learning a breathing technique just because I looked healthier than the average wanderer? This was utter bullshit. Seven days of grueling travel, only to get rejected like this?

"On that note," Urokodaki continued, his voice calm but decisive, "I am not an ordinary person. I accept you as my disciple."

"Wa-wait, what?" I stammered, my thoughts grinding to a halt as I tried to process his words.

Urokodaki got up, heading toward the door without a word. Just as he stepped outside, he paused. "Your scent… it's of someone telling the truth," he said, then closed the door behind him and sprinted off into the darkness, leaving me completely dumbfounded.

Scent? Right, I remembered—Urokodaki and Tanjiro had an absurdly strong sense of smell. They could sniff out lies, emotions, and apparently… even people from other dimensions? I never understood how it worked in the show, and now that I'm living it, it still doesn't make any damn sense, But I was able to gather that this guy was just fucking with me the entire time, he knew my motives from the start

Maybe this was some kind of test. Did Urokodaki want to see how I'd react under pressure? Or was he just confirming what he already suspected? Hell, maybe he just enjoyed messing with me a little before giving me what I came for. I had no idea, and I wasn't sure I'd ever know. What I did know was that the end result didn't change.

Though, I do wonder, where exactly in the timeline am I? And didn't Tanjiro have to go through an obstacle course for an entire night straight? Why did I just get accepted so easily?

I shook my head. That wasn't very important at this moment. The more I explore the world, the more knowledge I'll naturally receive. What matters for now is getting a good night's rest to prepare for the training.

—--------

As dawn broke, I was jolted awake by a firm yet strangely gentle shake. Groggily opening my eyes, I was greeted by the sight of a red demonic mask inches from my face. My heart nearly leapt out of my chest, and for a moment, I thought I was under attack. Then it hit me—this was Urokodaki-Sensei. Right. Demon Slayer world. Water breathing training. I wasn't going to die. Yet.

Without a word, Urokodaki dropped a neatly folded set of clothes on me. The weight of the fabric forced me to sit up as I scrambled to catch it. "Get ready in five minutes, boy. Training starts today." His deep voice carried the weight of authority, leaving no room for argument.

Still half-asleep, I winced as I stood, the soreness in my abdomen reminding me of the seven-day trek it took to get here. "Already? But I…I mean, yes, Urokodaki-Sa—uh, Sensei!" I stammered, bowing awkwardly as he walked out of the room without another glance.

Urokodaki left the room, as I scrambled to take off my clothes and put these clothes on. It was difficult to wear old school clothes, with too many strings, and knots as compared to modern clothes where you can just put them on. After three minutes, I ran out of the room, only to see Urokodaki-Sensei waiting outside, looking at a bamboo almost filled with water. Was this some form of hourglass?

Urokodaki-Sensei looked over at me, analyzing my uniform. "You've worn it backward" He grunted, turning around and walking into the woods. I paused looking over at my uniform. I couldn't tell the difference between forward and reverse for this uniform, still, I'll try putting it on correctly tomorrow.

Hastily jogging after Urokodaki-Sensei I arrived near a waterfall.

"Your physical condition" Urokodaki stated looking at my sluggish condition "Is terrible, probably one of the worst I've ever seen. It doesn't help that you hurt your body even more, pushing it to the limits without proper sustenance. For this week, we will focus on some light training, focusing on the theoretical aspects of breathing techniques, and the proper stances on how to hold a sword"

I beamed, I'm glad my teacher was sensible enough to not put a physically unfit child in intensive physical training.

"Go sit under the waterfall"

My smile vanished. Nevermind.

I looked down at the waterfall. It went down endlessly. The force of the water rushing down could easily crush rocks. "S-sensei, are you sure this is safe? Won't my body break from this?"

"Stop complaining and go already" Urokodaki-Sensei grumbled, lifting his leg and kicking me off the ledge towards the waterfall. I am not proud to admit it, but I did scream like a girl as I plunged down towards the waterfall. Urokodaki-Sensei did not comment on my scream, as he just shouted instructions at me.

"Sit under the waterfall, and concentrate on the feeling of water splashing down at you" This guy, did he just tell me to focus on water after nearly kicking me to my death?

"WHAT THE HELL OLD MAN? WHAT IF I DIED OR DIDN'T KNOW HOW TO SWIM?"

"If you died from something like this, you're not fit to face demons, as for swimming, do you really believe you'll be able to master water breathing if you don't even know how to swim? Now, less talking and more training brat"

—--------

Urokodaki-Sensei handed me a wooden sword, as he held one up by himself."We'll begin with fundamental sword swings. Watch closely."

I gripped my sword tightly, my gaze locked on Urokodaki-Sensei's form, determined not to miss a single movement. "Yes, Sensei!" I responded, my voice steady despite the nerves bubbling inside me.

Without another word, Urokodaki began his demonstration. Despite his age, his movements were anything but frail. Each swing of his blade was deliberate, precise, and fluid, as though the sword was an extension of his very being.

The air seemed to hum with every strike, and a sharp whoosh followed in its wake. The sheer force of his swings generated small shockwaves, ruffling my clothes and blowing my hair back. I stood frozen, unable to tear my eyes away, mesmerized by the sheer elegance of his technique.

"Now you try. One hundred swings to start"

my eyes widen "One…one hundred? Alright fine, I can do this" I picked up my sword, as I started swinging my sword relentlessly. My form, initially enthusiastic quickly became sloppy as fatigue settled in.

Urokodaki-Sensei looked at my swings with complete focus."Focus, boy. Each swing should be as precise as the last"

"Right…precision. Like…support item designs. Every detail matters"

"...I do not know what that means, but you are correct, every detail matters"

Hours pass, as the sun starts to set while I continue to practice my basic sword swings. As the sun completely set, and night began, Urokodaki finally signaled me to stop my swings, and I let my trembling arms down with a groan.

"How did I do?"

Urokodaki stood still, silently contemplating my performance for a while. He finally nodded his head as he turned towards me. Maybe he wanted to find something inspiring to say to cheer me up for doing terribly.

"That was absolutely terrible"

Never mind

"I see"

Urokodaki-Sensei stepped forward, his voice softening slightly. "We have much work to do if you ever hope to become a Demon Slayer. Your resolve is admirable, but your body is weak, your technique non-existent"

While I expected this answer, it still stung a bit, reminding me of my last life. Nevertheless, I would rather face a hundred demons than go back to my old self. "I understand Sensei, I'm ready to work harder"

"Good, then follow me. Your training ends today. Get some food, we will start endurance training tomorrow. It might take a long while to train up your body to become acceptable as a demon slayer."

—--------

"It appears I was wrong"

Both I and Urokodaki-Sensei assumed that it would take months for me to be able to complete the workouts, what with me having terrible physical parameters and all that.

And yet, three days later, I was crushing it. Running laps like it was nothing, swinging a sword hundreds of times with no fatigue, and sitting still, not being affected by the waterfall whatsoever.

Urokodaki-Sensei suspected of me becoming a demon, however, upon seeing me in the sun he dispelled such thoughts.

"Your rate of progress, it's…the fastest I've ever seen. Were you born with a special body AYD?"

"i-I don't know Sensei"

I, in fact, did know.

From what the void told me, every time I enter a world I gain that world's physique. Since I come from the MHA world, I possess a ridiculous physique. I'm not sure if it's because of Quirks or because of the increased danger, but the people from my world can train their physical bodies to insane standards, being able to break walls and run faster than cars with just their physical abilities alone.

It's probably because of this physique that I can progress so fast in this training.

"Regardless of your physical circumstances, I believe you are fit enough to start learning Total Concentration breathing"

My eyes narrowed. Finally, the main thing I wanted to master in this world.

—-----

"No, that's wrong"

Urokodaki-Sensei screamed at me, striking a specific place on my abdomen, and making me breathe out with a pained gasp.

"Remember which area is hurting, and how you exhaled the air when i punched that area. Imitate that way of breathing. Remember, Total Concentration isn't just a technique, it's your only defense against a demon, don't half-ass this"

Gritting my teeth, I breathe in again, only to be struck on the abdomen yet again.

—------------

During nighttime, I put boulders on my back as I started running through the obstacle course that Tanjiro went through in the first episode. During the entire course, I was instructed to maintain Total Concentration while watching out for traps.

Not only did my lungs hurt from the constant use of Total Concentration, but the pain from my back and lungs, and lack of air made it hard for me to focus on my surroundings, often triggering traps like swinging logs or falling in deep pits.

Regardless of whatever trap came in front of me, I had to overcome them. If I can't even master a normal breathing technique, what chance do I have to survive in worlds far more dangerous than this world?

So all I need to do now is shut up and move it.

—------

"Faster, more power, don't swing too far"

Urokodaki-Sensei shouted instructions at me as he parried my sword strikes with ease, using only one hand. His movements were unpredictable and fluid, able to fit in gaps and turn in weird shapes with extreme fluidity.

"Your movements are too stiff. You must understand water and flow with it, not stand in one place and flail your arms around"

His swords struck my arms, the pain almost making me drop my sword. But I held on it tight as I continued my relentless assault of strikes on him.

—------------

"Water breathing: First form- Water Surface Slash"

A stream of water emerged from the katana I was holding, as I easily cut down the stack of bamboo in front of me.

"Not bad, it takes most people a year to master water breathing, but you did it in just 3 months"

Urokodaki-Sensei looked at the clean slash on the bamboo sticks. As Urokodaki-Sensei began to say something, the cry of a crow echoed throughout the forest. A crow flew in, handing Urokodaki-Sensei a letter.

He took the message, unrolling it as he read the contents. A while later, Urokodaki-Sensei took out a paper and quill as he wrote a letter. He handed it to the crow as the crow cawed and flew away.

Urokodaki-Sensei looked back at me "It looks like another student is on his way here."

Another? Wait.

"This new student, what's his name?"

"Tanjiro Kamado"