[Multiverse]Voyage Through The Worlds

"""""WHAT"""""

Chaos suddenly erupted within the meeting. The atmosphere of the meeting changed in just an instant.

The Twelve Kizuki were divided into two groups. The 6 Lower Moons and 6 Upper Moons.

From these two, the Lower Moons were considered the weaker group. While they are not as strong as the Upper Moons, the strength they possess far exceeds that of even high-ranked slayers, and typically require someone as strong as a Hashira to kill them.

All requirements to ascend to the position of Hashira could be ignored as long as a person killed a Lower Moon on their own. Theoretically, even a swordsman not a part of the Demon Slayer Corps would be granted the title of a Hashira as long as the proof of killing was presented.

Not to mention, even though the Lower Moons are not as strong as Upper Moons, they are unbelievably arrogant and narcissistic to the point where even an Upper Moon might blush.

The reason for this is that, compared to the centuries of fighting and life-and-death battles, Lower Moons usually only ascend to their position after the death of another Lower Moon.

Not to mention, most Lower Moons don't even fight in Blood Battles. 

Blood battles refer to when two demons fight to the death to either settle differences or move up a rank. As the name suggests, this is a battle to the death. However, due o the fluctuation of Lower Moons, blood battles have become something exclusive to Upper Moons.

As such, while Lower Moons are certainly powerful, they are not almighty. Every now and then, the Slayers Corps is able to find the location of a Lower Moon. This makes it so the positions of the Lower Moons are constantly rotating, and the demons are constantly being replaced. Even Tanjiro, someone who hadn't mastered Total Concentration Constant, was able to defeat a Lower Moon, though in the end it was Giyu who killed him.

Former Lower Ranks One (Ubume) and Two (Hairo) were killed by Sanemi Shinazugawa and Kyojuro Rengoku, respectively, their deaths instantly promoting the swordsmen to Hashira.

However, the Upper Moons are a ridiculously big deal.

Strength, speed, durability, endurance, stamina, experience, mastery over Blood Demon Arts, and combat mastery. Upper Moons exceed Lower Moons in pretty much every category possible.

While the Lower Moons kept on changing, the Upper Moons haven't changed once in hundreds of years. These demons are so powerful that Shinobu once stated that one Upper Moon contained power equal to three Hashira.

There is no information regarding the whereabouts, abilities, or even the appearances of Upper Rank Demons. These demons are so strong that even if a Hashira were sent in as a messenger, it would end up in the Hashira's death.

'So naturally, when information about the Upper Moons appeared.'

Sanemi and Tengen immediately got up in shock. Gyomei stopped praying. Giyuu's unfocused eyes locked onto my face, and Shinobu Kocho's face displayed seriousness.

"Hey, kid." Tengen said, his face serious, "Are you sure of what you're saying?"

'The Hashira were unable to believe it.'

It wasn't just Tengen that was tense. Every Hashira present had an inquisitive look on their face.

Information about Upper Moons was almost impossible to obtain, so naturally, every Hashira and even the Corps Leader, Ubayashiki Kagaya, had their doubts. It didn't help that the one who delivered this news was a Mizunoto, the lowest rank signifying a complete newbie.

"Aoyama-San," Shinobu said, her eyes fully locked onto mine, "I hope you have a way to prove this information."

"Naturally, um?"

As if she understood my question, she nodded before getting up on both legs.

Shinobu Kocho was unique.

Her eyes were completely purple, lacking any sort of distinction for a pupil. Not to mention, those unblinking eyes betrayed any form of emotion, except for a tiny glimmer of rage radiating within them.

She was pretty.

I'm scared of pretty women. I much prefer fighting man-eating monsters.

"My name is Shinobu Kocho. I am the insect Hashira."

[Shinobu Kocho- Insect Hashira]

"Since Oyakata-Sama has been calling you using your first name, feel free to call me by my first name as well."

"I see," I said, nodding. " But first, what do you mean when you say Insect Hashira?"

Of course, I knew what it meant, but for the sake of appearances. I had to ask. Shinobu Kocho used Insect Breathing, a derivative of Water Breathing.

"I understand your confusion. My breathing style is called Insect Breathing," she paused for a bit after saying that. To put it simply, it is a derivative of Water Breathing.

As you can see, my body is quite short, which makes it extremely hard for me to decapitate demons due to the insufficient leg length and leg strength I possess. To make up for that, I developed a Breathing Style completely tailored to stabbing demons instead."

"Wait, but aren't you a Hashira now? I asked in confusion, "Shouldn't you have enough physical strength to behead a demon by now?"

This is a question that bugged me in the old world. Even if her body type wasn't strength-oriented, the boost from Total Concentration Constant should have been more than enough to grant her superhuman strength.

"Of course I do now," Shinobu nodded. "However, I have gotten used to Insect Breathing, and my equipment is centered around my specialization as well. Switching breathing styles at this point would be inconvenient."

She then withdrew her sword before holding it in front of me.

"As you can see, the blade is thin and fragile, making it unfit for decapitation or defending myself. However, the blade is excellent for stabbing." She said, twirling her sword, " It is coated in Wisteria poison, which is deadly to demons. Each stab injects a tiny amount of poison within the Demon I face."

"So you specialize in poison?" I asked as she nodded, "Well, that's perfect, considering Upper Moon 6 also specializes in poison."

"Is that so?" Shinobu replied, her eyes narrowing.

However, it looks as if Sanemi has gotten tired of this little charade.

"Hey, brat," Sanemi shouted, clearly agitated. "How about we stop this little Q&A session, kill the suspense, and give us some actual information we can use? And don't you dare call me by my first name, it's Hashira-Sama to you, got it?"

"Sure, whatever."

"Grr"

"...Can we please get the details already?"

Looks like even Giyuu was getting restless.

"I agree with Giyuu." Ubayashiki nodded, chiming in, "The location of an Upper Moon is a matter of great importance."

"Of course." I said, nodding, "To start off with, how many of you are familiar with Yoshiwara's Entertainment District?"

"The Entertainment District..." Giyuu trailed off, "It is a place where people attempt to fill their hollow hearts, devoid of love, with lust. It is a place I utterly loathe."

The hell? What's with that description?

"It's a place for losers," Sanemi scoffed. "Old men who can't find a wife try to make themselves feel better by sleeping with some pretty woman."

"A place where cowards sell off helpless women because they weren't capable enough of earning money on their own." Shinobu scoffed.

"Namu Amida Butsu," Gyomei replied with his hands in a prayer position. "It is a place where helpless women must indulge in the cruel desires of men. It is a place filled with the sorrows of hundreds of innocent maidens."

It's amazing how someone with basic human empathy is so hard to find, that when you find one, you can't help but be amazed.

"A place that sleeps during the day, and is awake during the night." Tengen chimed in, "It is a perfect place for a Demon to hide."

Looks like his title as a Shinobi isn't for nothing, huh? Immediately analyzing and dismantling scenarios based on the given information.

Yoshiawara Entertainment District was exactly as it sounded. It was basically a big legal brothel of this era. It was a place filled with many houses that had prostitutes of different ranks within them, and as is with most brothels, they're especially crowded during nighttime.

(Yoshiwara is a real place. If you're interested, you can Google it.)

"Moreover," Tengen continued, "Since most women working in the Entertainment District don't do so of their own free will, they often run away as well. I believe it's become so common that they have a term for it. I believe it's called Ashi-something?"

"Ashinuke," I supplied, "It's a term to refer to a worker who ran away without earning enough money to pay off their debt. Since it's considered a forbidden taboo, people don't discuss it and generally try to avoid the women who have run away."

"A place that's only active during the night, where people immediately stop talking about a person if they disappear," Shinobu murmured. "That's a perfect place for a demon to grow."

As soon as the words left her mouth, every Hashira once again had a tense look appear on their face.

"A perfect place for demons to grow?" Giyu repeated, "...Maybe there are other demons there as well?"

"No way," Sanemi dismissed with a scoff. "Demons are territorial creatures. There's no way an Upper Moon would tolerate another demon's presence in their turf."

"He's not wrong," Tengen chimed in unhelpfully. "Even normal demons can detect demons much more easily than the Slayer Corps, let alone an Upper Moon. If one truly resides there, then we can be sure there are no more demons residing in that place."

"If that's true in the first place," Sanemi said, "How do we know if this brat isn't just making this stuff up?"

"My disciple is not a liar. Gyomei firmly stated

"Gyomei," Sanemi turned towards him, "Are you sure about tha-"

*thud*

Out of nowhere, Sanemi fell to his knees, gasping for air.

"You-"

"I am sure," Gyomei once again repeated.

Sanemi glared at Gyomei for a moment, before drawing in a quick breath.

"Tch," Sanemi scoffed, getting up. "You sure are violent for a former monk."

"Oyakata-Sama," Gyomei said, ignoring Sanemi, "Perhaps we should send some informants to the Entertainment District. Even if the information turns out to be false, it is simply too convenient a place for demons to grow."

"Unfortunately, that is not possible," Ubayashiki shook his head. "The Demon Slayer Corps does not have many females trained in the art of combat or espionage, and even then, most women would not wish to voluntarily join the Entertainment District."

Of course, that much is obvious.

The Yoshiwara Entertainment District is a gathering place for prostitutes. If a female truly wishes to infiltrate one of the houses, they must maintain their disguise by actively participating in sexual activities.

Not many women, even including the ones in the Slayer Corps with a profound hatred for demonkind, would wish to sell their bodies.

"I see," Gyomei whispered, "A fair point."

Even though Gyomei wished to see the destruction demons, he did not want to put innocent lives at stake, much less the chastity of the young maidens within the Slayer Corps.

After all, that is the only remaining possession many of them have left.

As for men...of course, no house is going to hire them. Even the workers and cleaners working there are women.

It can't be helped, the intention of men joining a prostitute house is clearly visible after all. Even if one did not wish to join for sexual reasons and purely because they required money, how long could they stay sane after hearing the grunts and moans of women and men?

Definitely not the men during 1912's I'll tell you that much.

"But man, what a coincidence," Tengen murmured, scratching his chin. "I was just about to send my wives there to gather some information."

"Yeah," I nodded, "...A coincidence."

"Why the unnecessary pause?"

"Brat, you got any information regarding the demon?" Sanemi asked, "Any abilities or something?"

"Yeah." I nodded. "Honestly, it's a bit of a weird situation."

"Weird how?" Ubayashiki asked

"Well, starting off, there's a major house called the Kyogoku house. The Warabihime Oiran of that house is called Daki, whose eyes have Upper Moon 6 imprinted on them."

There are ranks in the Entertainment District. The Oiran is considered the highest rank in a house. Oirans don't just do sexual favors, but also spend time with the customer, much like a modern date, doing things like tea ceremonies or artistic crafts as well. However, to rise to the rank of Oiran, one must inevitably rank up from the lower positions, which include sexual activities.

"So this Daki is the Upper Moon?"

"No," I shook my head. "While Daki is extremely strong, she mainly has her rank thanks to her brother."

"Huh?" Sanemi shouted, "So we have to fight two members of the Twelve Kizuki instead of one?"

Frankly, the Upper Moons have every advantage over Hashira. Physical differences aside, the Upper Moons have been alive for thousands of years, constantly fighting and eating as compared to Hashira, who rarely live past 30. The sheer experience they possess can allow them to overwhelm a Hashira even in pure combat.

Even if a Hashira possessed the Slayer Mark, Transparent World, and the Red Blade, they would only be able to match the weaker 3 of the 6 Upper Moons. The top 3 Upper Ranks would require multiple Hashira possessing this skill to match them.

Upper Rank 3 Akaza was able to defeat Tanjiro Kamado and Giyu Tomioka, even though both of them possessed the Slayer Mark. Even cutting off Akaza's neck did not kill him, as he could regenerate his head. However, after suffering the fatal injury, he remembered his past life as well as his wife, whom he loved so deeply, that even as a demon, he instinctively refused to eat women. In the end, he did not wish to live on longer as a man-eating demon, so he killed himself and rejoined his wife in the afterlife.

Upper Rank 1 Kokushibou was able to fight off Tokito, Sanemi, and Gyomei, even with the three of them possessing the Slayer Mark and the See Through World, and a demonified Genya who could use Kokushibou's BDA. In the end, Kokushibou, who used to be a Samurai, grew disgusted upon seeing his horrific demonified face. He remembered his human life along with his brother Yoriichi. After seeing his state and remarking that he is still nowhere close to his brother's strength, even after thousands of years of training, he just gave up his regeneration, killing himself.

In the end, the Hashira only won against the Upper Ranks because of Sheer Luck, and even then. Only Giyu and Sanemi survived the fights, with the rest of the Hashira dead. Giyu and Sanemi used the Slayer Mark against the Upper Moons, so both of them died before 25 as well, which, considering their age, was barely a year or two more.

So for the Hashira, having to fight two Upper Moons was a disaster.

"Mm, basically," I nodded. "Gyutaro hides within Daki's body. If the situation ever gets out of her control, Gyutaro will come out of her."

"He hides inside his sister?" Sanemi murmured, "Freaky bitch."

I could insert a Sweet Home Alabama joke here, but I doubt they would get it.

"Aoyama-San," Ubayashiki gently asked, "How strong would you estimate her to be?"

Daki is a unique case. She's not as strong as an Upper Moon, but she is dozens of times stronger than a Lower Moon even in her weakened state. After merging with all her cognitive obi slashes, her hair turns white, allowing her to fully unleash her strength.

"Hm," I hummed, "Definitely stronger than any Lower Moon, that's for sure. From what I know, she has devoured at least 7 Hashira."

"Seven Hashira," Ubayashiki murmured. "Seven children."

For a moment, a look of rage appeared in his otherwise tranquil eyes before disappearing instantly.

"Oyakata-Sama" 

"It's fine, Gyomei. If nothing, at least killing this demon will grant some peace to departed souls."

What a kind man.

Anyways.

"Right, so," I continued, "Daki's Blood Demon Art lets her create flower-patterned obi sashes from her own flesh. She can control them freely, and because they're so soft and flexible, they're a pain to cut through, though considering you guys are Hashira, I'm sure you won't have any problems.

The sashes also have a weird ability. She can trap people inside them by flattening them into two-dimensional forms, like paper. It's how she stores humans until she's ready to eat. To free someone, you have to slice through the sashes without hitting the person inside. Do it right, and they pop back to normal instantly.

Also, she has the ability to create obi sashes with cognitive functions as well, which she does to guard and protect her "storehouse," where she keeps her food. By the way, these cognitive slashes require her to give up a portion of her strength."

"I see," Tengen nodded. "Do you know where this storehouse is located? Before we attack the demon, we must save the civilians and try to contain her sentient obi slashes."

"Um, I think it's somewhere inside the Tokito house, in between tiny cracks? I'm not entirely sure, you're gonna have to do a bit of investigation."

"I see," Tengen nodded. "I will send some mice to scout that location."

"As for Gyutaro," I continued, "He actually possesses multiple abilities.

The first lets him completely control and manipulate his own blood. He can use it to create solid weapons, whips, or long-range projectiles.

The second ability lets him generate extremely lethal poison. Keep in mind, he can coat his body and blood with poison, so even a small wound is deadly. Combine that with his long-range projectiles, and it's deadly."

"What exactly do you mean by projectiles?" Kyojuro asked

"Hey flame brat, shut it, this is Hashira business," Sanemi snapped before turning to me. "That said, answer the question."

"It's complete manipulation of blood," I shrugged. "Arrows, bullets, whips, cages. The only limit is his imagination."

"Fan-fucking-tasting."

"Also, he is extremely skilled with a Kama. After using one for hundreds of years, I'd say he's probably the best user of that weapon on the planet."

"What a pain," Tengen murmured. "Close range and short range?"

"You think that's bad? The final ability lets him detach his "core," so as to speak, and implant it within his sister's forehead. Not only does this make Daki stronger and let them communicate psychically, but it makes it so even if you cut off Gyutaro's head, he won't die."

A demon that won't die even if its head is cut off.

Every Hashira's face tensed the moment they heard of that.

Such a terrifying possibility was never even thought of before, yet now it has turned into reality. Not only do they have to fight off an Upper Moon, but they have to fight one that can't be decapitated?

For the first time, the Hashira felt a sense of helplessness. Why were the demons, the incarnation of evil, so much stronger than the humans?

"Just to be clear," Shinobu asked, "This is the weakest Upper Moon, right?"

"Unfortunately, yes" I nodded,

"Namu Amida Butsu, the forces of evil have started solidifying themselves on this pure world. If we do not make haste, we shall lose all we know."

"Lose all we know..."

Technically speaking, that's both wrong and right at the same time.

While demons are superior to humans, the bombing of Japan during WW2 will display the unmistakable might of human intelligence and technology. Even a human hater like Muzan Kibutsuji will not be able to deny humanity's potential after that.

After that, there are two choices. Either Muzan continues on normally, but instead of sticking to Japan, he might go on towards the rest of the world and turn a larger portion of humanity into demons.

However, doing that risks the fact that a stronger demon than Muzan may show up.

The second option is that Muzan goes about it the smart way. Spreading his influence and turning the leaders of the countries into demons. If something like that is done, then Muzan will truly have control over the entire world.

In the first choice, humanity will inevitably put their differences aside and band together. In the end, it will turn into one of those apocalypse Shonen where the entire world is filled with some enemy that humanity must defeat, like Kobaneri of the dead.

This option is still viable. While humanity might go extinct, in the end, their rate of development, their strength, everything will grow at a terrifying rate. Humanity might have a chance at winning, even if a very minuscule one.

The second option is far more terrifying. Muzan Kibutsuji does not care about the development of humanity in the slightest, instead maintaining control over every influential person.

If we follow the second one, then humanity will slowly deteriorate without even knowing the truth. Protests, rallies, wars, Muzan would find such concepts entertaining. In the end, humanity will die off none the wiser while blaming other humans.

'Come to think of it, wasn't that pretty much the situation in my original world before I died?'

Something to think about.

"Won't die?" Shinobu asked, "Then how do we kill him?"

"We have to decapitate them both at the same time," I said as if stating the obvious.

"Seriously?" Tengen gawked, "Not only do we have to face two Upper Moons, but we somehow have to magically communicate with each other to kill them at the same time?"

"It sounds tedious," Giyu noted, "From the provided information. Not only do we have to emerge without a single injury, which is impossible against an Upper Moon, but we have to time our attacks as well."

"It sounds difficult as hell," Sanemi frowned. "The twins have the upper Hand in everything. Speed, strength, regeneration, experience, long-ranged combat, short-ranged combat, and, if what this guy said is true, even communication. Unlike us, they will have no delay in communication, and most simultaneous attempts at decapitation will probably end in failure."

"Decapitation isn't the first thing we should be concerned about," I countered. "The first thing we need to do is rescue the civilians trapped within her sashes and find a way to counter their poisons."

"I propose we rescue the civilians during daytime," Shinobu interjected, "While it is risky to send in members during daytime, it is far more dangerous to rescue civilians while fighting an Upper Moon who can control their fates with just a flick of her wrist. Should she feel threatened, she might use them as hostages."

"Aoyama-San," Ubayashiki asked, "Could you tell us the approximate strength of the Obi slashes guarding the civilians?"

"Let's see."

In the anime, when Inosuke discovered the hideout, he was able to pierce the slashes pretty easily, wasn't he? At that time, Inosuke had been using Total Concentration Constant for a while.

"They're not stronger than someone who can use Total Concentration: Constant."

"Oh wow, that's it?" Tengen mocked, "That's a really low bar, right? I mean it's just Total Concentration: Constant isn't it?"

"Listen, that's pretty much all the information I have," I said, shrugging my shoulders. "I can't exactly find out every single thing about an Upper Moon, can I?"

At that answer, Tengen sighed.

"That's reasonable, I guess," Tengen shrugged. "I can first-hand attest to the effort it requires to gather information."

However, as Tengen reached the end of his sentence, his speech devolved into slow murmurs as he squinted his eyes in doubt.

"Speaking of gathering information," Tengen said, "How exactly did you gain such exact information?"

'...Ah.'

While I appeared calm, at that question, I internally panicked. Instantly, every Hashira's gaze fixed onto me, full of wariness and suspicion. 

Honestly, I shouldn't be surprised at this turn of events. It was only natural for the Hashira to suspect me of something after providing such a detailed explanation.

'Which is why I prepared an alibi.'

However, if this story of mine failed to be adequate enough, I could only imagine the consequences. At best, they might just think of me as providing false information, which will have dire consequences.

But, in the worst-case scenario, they may think of me as someone working under the Upper Moons. If the Hashira reached that conclusion, I don't think I need to explain what will happen to me next.

"I saw it."

"Saw it?"

"Yes, before I joined the Slayer Corps, I was in a desperate search across Japan." I nodded while lying, "That's when I encountered the Yoshiwara district, so I entered the place with the disguise of a customer to gain basic information. It was then that I happened to come across a rumour."

"A rumour?" Sanemi asked.

"Yes," I nodded, "It's said that there existed multiple beautiful and cruel Oiran with the suffix of hime at the end. These Oiran would slant their head when angered. I got a bit curious about that rumour, so I wanted to find out more."

"Hm, I see," Tengen nodded. "So you wanted to get laid, and happened to come across an interesting rumour?"

"I wouldn't have minded getting laid," I sighed, shaking my head with a smile, "But I don't want my first to be a prostitute."

"How noble," Sanemi muttered with a scowl. "Tough luck, dipshit, that was probably your only chance to get some. Now that you've entered the Slayer Corps, the only way you're getting out is either dying or becoming a senile old man with a limp dick."

"There are ladies here," Shinobu remarked

"Where?"

"I for one think it's quite flamboyant," Tengen said with a smile. "But that still begs the question, why did you enter the Yoshiwara district in disguise in the first place?"

"Hm, I can't exactly give you a reason," I said. "If I can chalk it up to anything, I guess it would be instinct?"

"Your instinct?" Shinobu asked, "I'm sorry, Aoyama-San, but that is a bit hard to believe. Even we Hashira don't possess the instinct that honed, so it is a bit unbelievable for a non-combatant to possess such."

A valid question. Atleast, that's what a normal person would believe.

However, thanks to my eyes, I could see the barest twitching of her arm and the twitching of her facial muscles. While her face may be blank, it's almost impossible to control your facial twitches unless you somehow get rid of those muscles.

From the way her facial muscles twitch and the way her eyes narrow, there is only one conclusion I can come to.

'I see,' I internally thought, 'She's already made up her mind about me.'

But why?

I racked my brains as I reviewed my actions throughout the entire meeting, revising all the conversations I had, but none of them indicated anything that would make her suspicious of me.

"I can assure you, Lady Shinobu," I said, nodding, "I possess unnatural instincts. You can even ask my cultivator, the former Water Hashira, Urokodaki Sakonji, or my current teacher, who is the Stone Hashira."

"I can attest to that," Gyomei replied. "His instincts are the best I have seen. His body can detect threats and act on its own without sending signals to the brain to ask for commands, as if his body is completely separate from his brain."

"I understand that you're gifted in this stuff," Tengen remarked, "But going off on a gut feeling is a bit too..."

"Let's do it" Sanemi remarked

"Huh?"

Tengen let out a startled cry as he heard Sanemi.

"Think about it," Sanemi continued on ignoring Tengen's cry. "The information provided is too detailed, even if the reason for obtaining such information is

"Enough about that," I said, shaking my head as I moved my hand towards my sheath. "Do not worry, this information is authentic. As for how to deal with their decapitation, I also have something for that."

*creak*

The creaking of metal echoed throughout the surroundings as I unsheathed my blade. Taking in a deep breath, I focused on the blade within my hand.

*ssssss*

"I recently learned a neat trick, you see."

'Martial Union: Hinokami Kagura'

The red blade sparked once, then caught fire. Within seconds, it combusted entirely, flames trailing along the steel and rising into the air.

"This is," Ubayashiki gasped, "User of the original breath, you have already mastered this?"

Indeed.

The red blade.

Normally, Nichirin Swords can turn into virtually any color, dependent on the user and their Breathing Style. However, there is one color that cannot be normally accessed: a shining bright red.

A red blade is considered to be a Sun Breather's trump card, considering other swordsmen utilizing other breaths can only awaken their own red blade by clashing their swords with a user of Sun Breathing, or by sacrificing their own life force in times of sheer desperation.

Normally, there are two ways to awaken the red blade.

Friction: Clashing two swords together with enough force that the friction generated between them produces a substantial heat buildup, causing both blades to illuminate in a bright red hue.

Pressure: Gripping a sword with an unwavering strength to exert immense pressure onto the metal surface. This focused pressure produces a localized heating effect, causing the blade to turn bright red.

Other than that, exceptions like Nezuko's BDA can also heat up a Nichirin blade to turn it into a red sword.

I first used this against the sound demoness, though it was completely unintentional and only lasted for a second or two. Ever since then, I have never tried to re-create it as I was already preoccupied with Transparent World. However, Martial Union with Flame Breathing naturally unlocked the Red Blade.

Yes, Flame Breathing, not Hinokami Kagura.

Martial Union with Hinokami Kagura was more of a combination of everything. Considering I can only use one breathing technique at a time, my passive Martial Union only strengthens one aspect at a time. So, it was either use Water Breathing all the time or use Stone Breathing

Combining the two breathing styles would have made a completely different breathing style with completely different effects.

However, with Hinokami Kagura, I could passively gain the benefits of all 5 breathing styles at once, even including breathing I haven't mastered like Thunder and Wind.

From Hinokami Kagura, I could deduce the effects of all the breathing techniques even without mastering them.

[ Water: Increased comprehension and brain speed. ]

[ Stone: Overall strengthening of the body, including internal organs. ]

[ Flame: Red Blade ]

[ Thunder: Increased nerve reaction speed, increased leg strength, as well as limited manipulation of lightning to stun enemies (Similar to Kaigaku's Blood Demon Art) ]

[ Wind: Overall speed increase. ]

However, unlike using just Water or Stone breathing, the effects provided by Hinokami Kagura are diminished. That is, my body will not get as strong with Stone Breathing, and my brain will not get as fast with Water Breathing, but in return, I will get all the effects at the same time. The only exception to this is Flame Breathing, with the Red Blade being of a higher quality with Hinokami Kagura.

'I wonder if this problem will be resolved when I evolve Hinokami Kagura to Sun Breathing?'

"Oh!" Tengen remarked, breaking me out of my thoughts, staring at my sword. "How flashy...I approve!"

"This is called the red blade," I remarked, "And its function is simple. It can hamper a demon's regeneration."

Yes, the ability of the Red Hot Nichrin blade is that it can stop or even nullify a demon's regeneration. Against the battle against Upper Moon 5 Hantengu, when Tanjiro struck him with his red blade, Hantengu was unable to regenerate for at least a dozen seconds. While that may not sound like much, Upper Moons can regenerate entire limbs in less than a second, and the top 3 ones can even regenerate their heads.

Furthermore, the red blade possessed by Yoriichi Tsukiguni was so potent that Muzan was unable to heal his injuries even after a thousand years.

"I see," Giyuu remarked, removing his eyes from my blade. "Even if they won't die from decapitation, this blade can at least stop them from regenerating their head, is what you're saying, right?"

"A ray of light for a hopeless situation," Gyomei said as tears fell from his eyes. "Truly, the Buddha is merciful."

"Not bad, brat." Sanemi said grudgingly, " Though, the question is how long it can stop regeneration for?"

"I'll be honest, it won't be long, barely around 10 seconds." I said, "Not only is the demon we face an Upper Moon, but I haven't even been in possession of such an ability for even a day. As a matter of fact, this is my second activation ever."

"10 seconds is a lot," Sanemi said. "Don't beat yourself up over it, especially against an Upper Moon."

Well, this guy is surprisingly not an asshole.

Weird huh? In almost every fanfiction I've read of this guy, he was always the one to butt his head against the MC and always the one who lost. 

'Looks like those guys just butchered up his character.'

"But there's no way a Mizunoto like you is fighting an Upper Moon."

Damn.

"I won't have to," I said, shaking my head.

"Hinokami Kagura: Dance"

Drawing in a deep breath, I surged forward without hesitation. My blade came down in a clean, blazing arc aimed straight at Sanemi.

"Wind Breathing second Form: Claws-Purifying Wind"

'Wind Breathing, acquired.'

*TING*

Which was swiftly countered by Sanemi's own blade. Unleashing four vertical slashes at once to counter my dance. Almost immediately, Sanemi dashed back.

"The hell are you doing?" Sanemi barked back, "And what the hell is that strength? Are you shitting me? Wait, why the hell did I use a technique on a newbie?"

"Look at your blade."

"The hell do you mea-"

Sanemi's words got stuck in his mouth as he gazed at his glowing red blade.

"All I need to do is clash swords with yours to make it red," I said with a smug face.

"That's why you attacked me?' Sanemi barked, "Dumbass, what if I accidentally killed you, huh? Do you think of us, Hashira, as a joke?"

"It is because I respect you that I attacked you," I countered. "If a Hashira cannot control their strength, they aren't fit for the title."

"Who the hell do you think you are deciding the requirements for being a Hashira, huh?"

*ting*

The sound of metal ringing broke Sanemi out of his yelling as he looked downwards.

"What?"

Only to find Giyuu hovering his sword above Sanemi's Red Blade.

"It really turned red," Giyuu remarked, watching his blade slowly turn red from Sanemi's blade.

I could make an STD joke here.

A man's blade turning red from another man's blade.

'Wait,' I thought for a moment as my eyes slowly widened, 'what if a man's blade gets red from a woman's red blade?'

"The hell do you think you're doing, Tomioka?!" Sanemi shouted.

"I wanted to see if my blade would turn red too." Giyuu remarked, "I was a bit worried it wouldn't."

"Why the hell would it not turn red?" Sanemi asked in confusion

"I use Water Breathing," Giyuu countered. "I thought maybe my Water Breathing would extinguish the Red Blade."

"...Are you serious, Tomioka?"

"HAHAHA" Tengen laughed, "I love seeing those two bicker, it's the only entertainment I get."

"Are you saying the Hashira meetings are only a source of entertainment for you, Tengen?" Shinobu remarked

"No, Kocho, wait, don't start any misunderstandings. I get plenty of entertainment with my wives."

"On the topic of the Twelve Moons." Ubayashiki interrupted, "I have acquired some information as well."

Instantly, everyone became silent.

'Another one?' I thought with a frown, before realization struck me 'Wait, isn't this the plot from Rengoku's story?'

"Oyakata-Sama, please share it with us," Shinobu asked

"Of course, my dear," Ubayashiki gently replied. "It appears there have been sightings of yet another demon part of the Twelve Moons."

~~~~

Author here, who's hyped up for Infinity Castle??