Disclaimer:

I do not own nor claim all the rights to 鬼滅の刃 | Kimetsu no Yaiba | Demon Slayer; all rights are reserved to its respective creator, Koyoharu Gotōge. This is purely a work of fiction; names, characters, businesses, events, localities, and occurrences are all extrapolated from the author's writings and imagination or utilized in a fictitious manner. As such, any direct or indirect references to actual entities, dead or alive, or events do not, in any shape or form, resemble the opinions of the author.

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"..." = Dialogue

'...' = Internal monologues

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"Every day I shall kill one thousand people in the lands we created."

"Every day I shall create one thousand five hundred people."

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*Splash* *Splash*

The blemished, mucky water reached up to their knees, forcing the two slayers to rely on the support of the other as they trudged through this network of natural caves and dilapidated sewage structures.

The somber hues of these concrete tunnels elicited a correspondingly subdued atmosphere; the caliginous conduit had no color to ostentatiously display, nor any vibrancy to lighten the burden on the spirit.

Thus, the Hashiras had only each other to find solace in this dreary setting.

This, though, was something they found no issue with whatsoever, and, in fact, it was something they actually preferred under any given circumstances—regardless of the time or place.

"Are you holding up okay?" Shinobu asked, slightly breathless from the onerous strides she had to make.

"More or less," Giyuu answered with curt, similarly worn out from the monotony of this trek.

With one arm wrapped around the other, the wounded—but determined—demon slayers forged ahead into the void; into the darkness, they were to confront their greatest enemy thus far, even as they logically stood no chance in their current states.

But, even as impending doom awaited them, they did not stop: for upholding their duties, for safeguarding the lives of the born and the unborn, and for the undying faith—engendered by their pure, palpable love—they had in each other, there was no question about the road they would partake in.

They will continue marching into that very darkness.

"And you?" Giyuu returns the gesture.

"I'm fine, don't worry about me," said Shinobu.

Giyuu raised an eyebrow.

"But you're worried about me," he observes.

"Yes, and?" Shinobu replied.

Giyuu is left perplexed, "... That's odd."

"What is?"

"You're allowed to be worried about me, but I'm not allowed to do the same for you?" Giyuu inquires gently, the tone of his voice evincing a light cadence and innocent intent.

The conveyance of this message was almost akin to that of a naive child asking a simple question—which, given the Water Hashira's lack of experience in terms of a proper childhood in the first place, is not a bewildering notion to entertain for this instance.

Shinobu, in her everlasting affection and tenderness towards her companion, felt a warm, giddy feeling blossoming in her chest upon hearing this sincere airhead say something with such genuineness.

Amid all the confusion and chaos that transpired, she often forgets that they had only recently professed their love for each other—that, not too long ago, her wildest dreams and imaginations were all nearly fulfilled within a matter of seconds.

How quaint it all feels now, the time before their confession—how their relationship has changed almost everything.

Shinobu smiled instinctively, "That's because you're hopeless without me."

"... Huh?" Giyuu gave off a dumbfounded look.

"Airhead as always," she giggled, invariably finding amusement in her partner's naivete.

The Water Hashira could only gaze at her jovial countenance with admiration, as he relished in carefully scrutinizing the charming expression manifesting before him.

Years of witnessing a fabricated expression on her lineaments had made him easily susceptible to the unfeigned bearing she had now adorned herself with.

In truth, he had always sought that side of Shinobu: the hopeful, confident girl whom he irritated with his dumb antics, whose cheeky grin presaged an impish comment, and whose smile exuded a natural joy.

This is what he had always wanted—what he had always needed.

The Insect Hashria, taking notice of his stare, spoke, "What is it?"

"You're beautiful," the Water Hashira answered instantly.

Tints of crimson flushed her face, while the rhythm of the heart kept apace to this heightened emotional sense.

"Blunt as always..." she murmured sheepishly, averting her eyes.

While Water Hashira never had a way with words, his simple and candid compliments were enough for her to fall for him over again.

Indeed, she had always been quite fond of their conversations and interactions; from their very first meeting, Shinobu had grown to adore his awkward honesty, his understanding and caring nature, and his strange ability to somehow lift her spirits whenever she was at her lowest.

Perhaps that was why the years since Kanae's death had been so torturous without end, because she did not seek him out when she needed it the most—he was not there to console, to guide, and to share.

Nor was she there for him.

She still could not fathom why she allowed herself to become distant, why she permitted herself to drift apart from his warmth—even if the desire to embrace him dwelled in the depths of her broken heart.

Shinobu knows she cannot compensate for the lost years, but she can endeavor to change whatever prospect holds for the two of them.

Because, now, the future is no longer bleak nor bereft of life. They are going to make sure of that. Together.

She turned to face him again, grinning from ear to ear, "But thank you..."

Seeing this, the corners of Giyuu's mouth curved upwards without forethought, "Don't mention it."

Perhaps this was what she desired—what she needed all along.

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He did not know who he was.

Or why he was born.

All he can remember was a void.

An infinite sea of nothingness; nothing to see, nothing to hear, and nothing to touch.

But this seemingly empty vacuum belied a more divine function.

Although he still couldn't discern any physical elements within this barren environment, he felt a sensation within his soul: it was a calling, beseeching him for his unconditional service to a higher being.

It was an order from his Creator, and the contents of such espoused a tremendously vulgar and coarse language.

Like a knife doused in the blood of its victim, the individual words of this tongue evoked a vicious and nauseating image—much like how the source of this directive herself bore an abhorrent appearance.

In what little he could sense, he felt the pure, unadulterated rage of his Creator.

She was spiteful and full of hate.

She sought to destroy all that was created—even if it was her creation.

And he was instructed to become the conveyor of her wrath, the messenger of her absolute fury to the world above.

She demanded blood. And he was to deliver her the blood of the mortals.

It was then that he finally realized his true purpose: to kill.

The illuminating clarity of this objective and the meaning of this existence brought him consolation.

So I do have a purpose, he thought.

So I am not disposable, it took comfort.

I am not a hollow existence, the being relished.

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*Splash* *Splash*

The resonance of each footstep echoed deeply throughout these barren chambers.

A shade of green and yellow now tinged the environment, while the stench of squalor permeated every corner, both of which attested to the gross decay that has long beleaguered this reticulum of pipes and shafts.

As the Hashiras waded through the channel, recollections of their mission came flowing like memories of a distant past; it all felt like a lifetime ago, especially after everything they'd been through.

It was under the auspices of these chambers that they experienced everything from pain, loss, fear, grief, shame, and guilt—all in the past, present, and future simultaneously.

Yet, it was also here where they found salvation, forgiveness, and love.

"It's funny," Shinobu suddenly says, breaking the transient silence that was hitherto present.

"Hm?" Giyuu queries.

"Walking through this place, it almost feels nostalgic now..." she remarks.

The Water Hashira momentarily tilted his head in confusion, unable to comprehend her words.

"But it's just water," he plainly points out, completely oblivious to what his companion was alluding to.

"I know that," Shinobu sighed. "But... don't you remember?"

"Remember?"

"Before we fought Osore, we were exploring a similar area," she clarifies.

"Right... I suppose it does hold a resemblance..." Giyuu's memories were finally jogging.

"Remember when you were walking directly behind me? And you said it because you liked watching my back," Shinobu teased.

"I was worried about your safety..." Giyuu mumbled, reeling from the embarrassment.

"Which was why it was so cute," she grinned.

"You certainly didn't think so at the time," he slightly turned his head, trying his best to hide the blush.

"That's not true," Shinobu lightly protested. "I've always found you cute, Giyuu—like a huggable teddy bear."

"Didn't you swing your katana at me soon after?" Giyuu suddenly recalled, as if Shinobu's comments went in from one ear and out through the other.

"That's your response to someone complimenting you?" Shinobu retorted with exasperation, a small vein protruding from the corner of her temple.

"I'm just pointing out a logical contradiction...?" Giyuu said with perplexity.

"In any case, the katana thing was your fault anyway," Shinobu huffed, disappointed that her partner didn't seem to fully appreciate her doting.

"Wait, how?"

"Figure it out yourself," she pouted petulantly.

"I did call you pretty, but I don't recall any reason for you to get angry at me," the Water Hashira contemplated with great effort.

The Insect Hashira, however, felt more provoked by this display of ignorance: "Gosh, are you actually this dense??"

"I suppose I am a little slow when it comes to these things..." Giyuu admitted.

"A little?"

Giyuu briefly eyed his partner, delaying his reply in order to ponder the implications of her words. He felt a faint ache as he glimpsed at her.

He looked back down, ".... Sorry."

Shinobu reciprocated with a look of incredulity.

"Why are you apologizing, Giyuu?" She inquires, knowing from past experience that Giyuu's apologies were often done at his own expense—regardless of whether they were merited or not.

"Because I can't pick things up quickly... I constantly annoy you with my stupidity."

Shinobu felt a weight pulling down on her heart. She hated seeing him like this.

If there's one thing about Giyuu she intensely disliked, it was his self-effacing tendencies; his propensity to be too hard on himself in every way imaginable.

While he is no longer questioning the value of his very life, he is still hesitant to fully embrace himself—to free himself from the shackles of self-doubt.

Shinobu frowned, "Don't say that."

"Don't speak ill of yourself..." she added softly.

"It's true though," Giyuu demurs.

"No, it's not," Shinobu swiftly rejected. "You may be dense at times, but that doesn't mean you are stupid."

Giyuu, however, retained his modestly downcast eyes, unable to either look at the Insect Hashira or compose a response.

But she continued to press on, "I enjoy talking with you, Giyuu. Because I feel like I can speak freely around you, and I know that you will return the favor with your awkward honesty as well."

"..."

She continued, "And I genuinely love how you always try your best when socializing, even if it doesn't turn out the way you want it to."

It was at this point when the Water Hashira finally shifted his eyes back to her, moved by her words and utmost sincerity.

"Also, you being dense is adorable more than anything else. It's one of the reasons I fell in love with you," Shinobu quipped, letting out a small smile.

Giyuu returned the smile, "I enjoy our conversations as well, Shinobu. Thank you for putting up with me."

Spotting his expression, Shinobu beamed radiantly, "Besides, how can you be stupid if you're good with numbers—that's the literal definition of being smart!"

"Mathematics?"

"Mhm!"

'So she remembers...' The Water Hashira felt elation within the spirit.

Seldom had he revealed much about his personality to anyone beyond Urokodaki, but he has always had an academic side that complemented his logical outlook.

For him, this underlying characteristic is reminiscent of a simpler time: a time before a raging, sullen spirit hollowed out his soul and left nothing in its wake—eschewing any passion or flame in his heart.

So, to have someone acknowledge this side of him—the traits and passions he supposedly suppressed out of duty, self-punishment, or a combination of both following his induction into the Demon Slayer Corps—was a pleasant surprise.

To have his beloved Shinobu, the woman who saved him from this terrible storm of despondency and desolation, acknowledge this made it all the more impactful.

Perhaps that is why she is a perfect fit for his airheadedness.

Unlike him, she's able to hark back to the smallest and most insignificant of details, even ones seemingly irrelevant at the time—Giyuu could have sworn he only succinctly mentioned this particular quality once or twice to her.

He admired her for her incredible intelligence and dedication.

His love for the petite, kind woman beside him continues to grow evermore.

"You're more impressive, with your medicinal and pharmaceutical knowledge," Giyuu added with levity, seeking to downplay his own interests and probe Shinobu's instead.

"Not at all," Shinobu answered gently, "both of my parents were experts in the field, so it was only a given that I would inherit that."

"Do you enjoy it?"

"Enjoy?"

"Do you enjoy studying it?" Giyuu elucidates.

"Well..." Shinobu excogitated deeply. "I do like running the medical infirmary and taking care of patients, and I do find enjoyment in researching different chemical concoctions..."

"But," she added wistfully, a great weariness drawn onto her countenance, "there are times when I get tired..."

"I see..." Giyuu acknowledges quietly.

"I suppose I've grown to become indifferent to working with Wisteria compounds," Shinobu reveals with ambivalence, as she did not wish to dampen the mood with her grievances.

Even though the weaponization of Wisteria mixtures is her defining characteristic as a Hashira and demon slayer, she feels a great indifference concerning her research.

While she is learning to take pride in this prodigious feat, it still leaves a bitter taste in her mouth; after all, her efforts in inoculating herself with the substance were both a painful and regretful course of action—cementing a streak of adverse consequences into the future, especially in relation to Giyuu.

If not for those visions—those ugly, tragic premonitions—of that future, she would have never thought to reconsider her actions.

It also directly led to the single worst and most painful moment between the two lovers: that godforsaken night when Giyuu revealed that he knew about her secret, and their subsequent—albeit, temporary—estrangement.

She has utilized her findings for selfish reasons, and it hurt her far more than the needle ever could.

She didn't want either herself or Giyuu to be reminded of this distressing memory.

"..." Giyuu was silent.

Not wanting to prolong this uncomfortable topic of discussion, Shinobu attempted to deftly transition the subject, "I'm sorry, let's move on—"

"Do you regret it?" Giyuu interjects.

"... I regret deceiving you," she answers dolefully.

"Don't blame yourself for that," the Water Hashira affirms. "I simply wasn't trustworthy enough."

"T-That's not true!" Shinobu exclaimed.

"Maybe. Maybe not. But I do know that Wisteria research has never been the same to you ever since your sister's death. You could've thrown it all away right then and there, yet you managed to retain that critical component of yourself—even if you changed everything else."

The Insect Hashira's eyes widened with astonishment; the Water Hashira was praising her for persisting, even if she didn't exactly know why—after all, he was hurt by her actions more than anyone.

"I think it's amazing how you managed to keep that part of your identity alive, Shinobu, even if it became unbearable at times because of how it reminded you of your past life—a life before all the pain, hate, and grief," Giyuu explained solemnly, easily being able to convey the essence of such nuanced feelings, ones that both had the experience to grasp completely.

"But I tried to conceal everything behind the veil of Nee-san's personality... I wasn't strong enough to stand on my own two feet—I still needed her help then," Shinobu contended pensively.

"Even if mistakes were made, even if you struggled to bear that burden alone, I think your passion for medicine has outweighed the hurt you endured. And I think that's an admirable quality..." Giyuu praised softly.

He continued, hints of melancholy beginning to manifest in his voice, "I wasn't strong enough to do that for myself. I made myself a mindless machine because I was too weak to keep a part of my humanity."

Shinobu shook her head, "You're wrong."

"How?"

"You have always kept your humanity, Giyuu," she started.

"..."

"You say I bore that burden alone, but I was ready to give it all up—I was ready to sacrifice everything for nothing. But you came to visit that day, remember? After Nee-san's death? Your words of guidance, understanding, and kindness helped me more than you think. If you hadn't chosen to visit me, I don't know where I would be right now..." Shinobu spoke emphatically, directly from the heart, as she was expressing her long-held gratitude for saving her all those years ago.

"Shinobu..."

"Also, your willingness to spare the Kamado siblings, in spite of the sister being a demon, is proof that you are far more than just a mindless machine," she tenaciously defended her lover—he deserved more than what he gives himself credit for.

"You give me more credit than what I deserve," Giyuu opined.

"Then why do you stand up for me then? Are you less worthy of praise than I am? I have made a great many mistakes, Giyuu. You should know that; I..." she struggled with the next few words.

Her brows furrowed as recollections of that agonizing time streamed into her head like pollutants into a river, "I know I hurt you deeply when you figured out my plan... And I am so, so sorry for not telling you—for abandoning you."

This, however, had the effect of reminding Giyuu of something else entirely: "No, I have to apologize for abandoning YOU. I left you behind after your sister's death; even as I watched from afar how you suffered and anguished, I didn't do a single thing... I'm sorry for that. I really am."

"That was my fault too! I should be the one apologizing! I didn't reach out when I should have, and you must've needed me more than I needed you!" Shinobu cried out, not wanting her beloved to denigrate himself even more than he already has.

"... I can't just absolve myself, Shinobu," a dispirited Giyuu replied.

"And neither can I, Giyuu," she said shakily.

The Hashiras were at an emotional impasse. Their minds and spirits were throbbing with the sharp release of unwanted memories.

They were, essentially, both trying to do the same thing: to vindicate their partners while disparaging their own records—both were of the same mindset, just from slightly different angles.

Because, fundamentally, they were two broken individuals seeking to right the supposed wrongs of a woeful past inundated with mistakes, regrets, and dire repercussions.

But, more importantly, something in the back of their heads told them they were still not worthy of the other—worthy as a moral individual, a capable warrior, or a loving partner.

That scourge of that self-doubt has lingered, even if it has been tempered throughout the course of this mission and with their relationship.

There is no definite resolution for such a condition; who you are as a person does not change overnight.

Nevertheless, the slow progression of time along with time around loved ones may gradually alleviate the core issue.

One simple conversation at a time.

And so, they continued plodding through the underground system in a deafening silence.

Yet, their hearts were collectively pouring out more than ever before.

Perhaps it was the fact that their long mission was finally coming to an end.

Perhaps it was the fact that they were practically marching to their deaths, and this one-on-one will probably be the last they will ever have.

Perhaps they didn't want to leave this Earth without any loose ends, whether that be the serious or unserious, the trivial or non-trivial, and the romantic or emotional.

One last time, they will learn more about each other—and, maybe, along the way, more about themselves.

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The first man he killed was a traveling merchant.

The slaying was almost instantaneous; the merchant was dead the moment he walked past the being—who was seated along the fringes of the dirt road.

The being didn't know the man's name or identity, but he did not care.

He was tasked with a mission, and he felt obligated—either by design or by choice, he does not know—to uphold this prerogative.

And so, the merchant was slain, and that was the end of it.

Nothing more, nothing less.

More humans had to die.

Still, a strange thought traversed the being's head: did the merchant have a hollow soul? A purpose?

It was most unexpected, as the being had not anticipated such an aberration to occur in his cognitive processes—one that had been preordained to do the biddings of his creator.

Was the merchant without a purpose?

Was the merchant doubting his own existence?

No, that doesn't matter.

Besides, a merchant is a merchant: his only purpose in life is to sell and buy stuff.

Nothing more, nothing less.

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*Splash* *Splash*

For a while now, the Hashiras did not utter a single word to one another—even as they clung on to each other, tightening their grips as well.

This uneasy atmosphere, one daresay, was even more suffocating than the foul odor of their surroundings.

But they longed to break this stillness; they longed to communicate with each once more, because they truly valued what remaining time they had together.

Because, sooner or later, they will have to encounter their enemy. And this conversation may not continue subsequent to that debacle.

Everything was on the line right now.

Surprisingly, it was the reticent Giyuu who took the leap of faith: "Shinobu."

Shinobu, somewhat taken aback by this abrupt maneuver, answered, "Yes, Giyuu?"

"Do you know where we are going?"

"Of course I do," Shinobu replied blankly, as if she was stating the obvious. "I was studying the blueprints for the city's old sewage system at Akihiro-san's place during our convalescence, and I managed to memorize the general outline of it. So, not only do I have a rough idea of where we are right now, but I also pinpointed some key locations where I think the demon might be."

"I see... That's good..."

"..."

"..."

"Giyuu, do YOU know where we're going?"

"..."

"..."

"..."

Shinobu then came to a striking revelation: "You have to be joking."

"What?"

"So you were originally thinking about going down there alone... without even knowing where you were heading in the first place?!" she yelled.

"I would've managed."

"Seriously Giyuu, that was actually stupid of you! Thank Kami-sama that I came along, otherwise you would've never found the enemy at all!" Shinobu was ruthless in her criticisms.

"I'm... good at improvisation..." Giyuu said indecisively.

"Gosh Giyuu, you really are hopeless without me," Shinobu muttered, finding amusement in Giyuu's comment—but not wanting to admit it.

Giyuu let out a small grin, "I guess I am."

Seeing this sweet expression from her beloved, Shinobu's stern attitude finally relented—she really is overly doting on him.

"And I'm hopeless without you..." she whispered abashedly.

"Is that so...?" The Water Hashira looked up, feeling delighted beyond words.

"Giyuu, I'm sorry about earlier," Shinobu offered an olive branch.

"I'm sorry too. I can be stubborn," Giyuu accepted.

"Then that makes two of us," she smiled.

"We may not see eye-to-eye on a few things, perhaps we never will. But I will always stand by your side, Shinobu, no matter what. Just know that," Giyuu returned with his staple, earnest conviction and wholehearted resolve.

"I know," Shinobu replied with graciousness. "And always remember that I will love you no matter what."

Giyuu's smile was now on full display, "I know."

Alas, one conversation at a time.

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Many have died at his hands.

All because of an ancient directive built into the very fiber of his being, delivered from a divinity that he can't even recall.

The clarity he once cherished was beginning to fade: each successive kill made less sense and felt more off.

What was his purpose? To kill.

But why? Because my creator said so.

Does that matter? Of course, it's the creator.

With no other reliable or reasonably credible pathway, he continued to journey down this life of wanton destruction and murder.

Despite his growing inner conflict, he realized that it was best to just ignore it; after all, his life has been given a purpose, a mission, and a reason to continue. What more does he need for his current state of existence?

That, however, changed on one fateful night.

He entered an old abode, hoping to find people to kill.

Instead, all he found was some old, feeble lady on her deathbed.

She's dying anyway, might as well finish the job.

Before he could proceed, however, something unexpected occurred.

"You're him, aren't you?" the lady suddenly asked in a strained and coarse voice.

"..."

"The bloodthirsty 'demon' everyone is afraid of," she slowly lifts her eyelids, looking straight into the being's eyes.

"..."

"Huh... You look quite normal actually, not like the depictions they have of you."

"..."

"Ah, I was hoping to die in peace. But I suppose I'll have to go out like his," she sighed.

This was odd.

In all his years of rampaging, the victims would always have a look of fear or disgust in their eyes as they fell by his blade.

They would scream for mercy, cry out of anguish, hurl insults with vulgar language, or a combination of any of them.

They would always become pitiful beings in the end. And even when they were alive, they were hollow beings: unlike him, they weren't preordained to fulfill a specific duty, so their lives were meaningless and without purpose or sense.

Yet this unextraordinary woman did not exhibit any of the aforementioned characteristics.

She was strangely insouciant.

She did not agonize over the prospect of death; she seemed content with whatever situation she found herself in right now.

This mystified him.

"Woman," his scratchy voice rang in the ears, "is your soul hollow."

"..." she did not respond.

"You serve no apparent purpose. So why do you not feel discontented? Why aren't you crying for help or begging for mercy like the rest of your species?"

The lady instead smirked, "It must be hard. To never be able to feel the bliss of contentment. The satisfaction that you've lived your life to the fullest—lived it on your own terms."

"What?"

"You ask what my purpose is. This is exactly my purpose: to live this life without regret," she illustrates clearly.

"Lies. You serve no apparent purpose. You humans were made with no purpose, therefore your soul is hollow and automatically without any meaning," the being snapped, refusing to accept the lady's delineation.

"Is that truly the extent of your understanding of purpose?" The lady posits.

"I have lived a life equivalent to three of yours, I am wiser and more all-knowing than you could ever be," the being rejoined.

"And even after living all those years, you still have not noticed? I pity you, demon. For, you are truly the one without a defining purpose."

Provoked at such outlandish notions, the being fired back: "Nonsense! I speak from the authority of a higher spirit! I am the primordial being to which the task of eliminating 1000 humans in these lands per day has been delegated!"

"Yet, despite all that, you still have not come to the fairly simple revelation that people are free to define their own purposes—they chart their own fates and destiny. That is the beauty about being a mortal human, much unlike an immortal spirit such as yourself," the lady astutely deconstructs his arguments.

The being grits his teeth, "How could a mortal being like you understand the weight of the task bequeathed to me? My Creator is of a higher class, of higher spiritual integrity—!"

"And?" she interrupts.

"I HAVE A PURPOSE! I KNOW WHAT MY DESTINY IS!"

"That's it? You know your purpose because someone else told you so? Who is this higher being you speak of?"

"It... The Being... It's..." The demon struggled to compose a coherent sentence, because he did not know the exact nature of his creator—only that it exists and it inculcated a goal within him.

Nothing more.

"See? You don't even know yourself," the lady comments.

"Argh!" The being growled at her in his anger.

"You don't know who deferred to you this task, nor why it did in the first place. If your whole idea of purpose is built around such unsteady foundations, then where does that leave you?"

"I know I have a purpose... I know my soul is not hollow... I have a purpose... A purpose..." The being repeated to himself, trying his best to weather this storm of mental tribulations.

"Quite the opposite, in fact," the lady intercedes.

"What did you say??" The being snarled.

"You are the one with a hollow purpose, or no purpose at all. You are the one mindlessly traveling through life with nothing but an unspoken obligation to fulfill—one you don't even know why you have to satisfy in the first place. Indeed, you are the one who has practically concluded that the entire value of your life is equal to the faceless directives of some higher power you don't even understand," she begins.

"You're wrong!"

"You are the one with a hollow soul, Utsuro."

"No... No...! No! NO!!" The being shouted in panic. "You're wrong! YOU CAN'T BE RIGHT!! I NEED A PURPOSE!! MY SOUL CAN'T BE HOLLOW!!"

He could've ignored the lady's soliloquy, he could've easily ended her life far earlier, but something deep within him had been whispering the same exact words to him.

He had already known, he just didn't want to acknowledge it.

He had tried to jettison those notions, but they were always there—always hiding beneath the surface, waiting to envelop him when he was most exposed.

And it worked.

He had always known perhaps.

His life was essentially meaningless, because, in spite of having free will, he was blindly following something even he didn't understand in its totality.

Why did he have to kill? Why is the crux of his existence merely to kill humans? Is that all his life will be?

If he faces death in the eyes, will he beg for mercy? Because he will then realize that everything had been for naught, that he had the capacity to change his destiny all along but blindly chose not to out of procedure.

Or will he face death like this lady: look straight into its soul, mock it, and even give it a name to further denigrate its existence?

Utsuro had always known that he was hollow inside.

The lady died in her sleep later that night. She died with no existential crisis to trouble her in those final moments.

Utsuro didn't kill her, nor did he seek to spare her—he gave into the machinations of the world.

As for himself, he had lost what little clarity he had left.

Now he just wandered the world.

Hoping to find what that lady found—hoping to die a peaceful and well-earned death.

..

..

..

..

*Splash* *Splash*

"Ne Giyuu?" Shinobu spoke.

"Hm?" Giyuu hummed in response.

"Why do you like math?"

"... Sorry?"

"I'm just curious, because you're awfully good at it," she replied plainly, with no dither or vacillation in her voice.

"Oh..." Giyuu acknowledges, giving it some thought.

"For the same reason I dislike philosophy or the humanities," he answered sardonically, specifically throwing flak at other fields.

This made Shinobu giggle, her expression now exuding a smile of sorts, "And why's that?"

"In school, I barely understood the texts we read, which included philosophy, literature, and the like," he expounded. "I especially disliked the Confucian readings we had."

"Oh my, those were quite gruesome. I myself could barely understand what each sentence was trying to say," Shinobu chipped in, providing her own personal tale in conjunction with Giyuu's.

Giyuu nodded, "Exactly. I would often reread the same sentence five times and still not know what it was saying."

"Right? They made no sense!" The Insect Hashira sympathized with this age-old predicament.

Excitement brewed within Giyuu, as the sharing of school experiences is something he often couldn't do for reasons ranging from having no school friends to joining the Demon Slayer Corps—thereby cutting his education short, like many other slayers.

He felt a faint grin forming, "And even when I eventually deciphered them, they speak as if they know the answer to everything, that it's somehow all logically sound. However, I would often find contradictions or fallacious statements in the texts, so I grew to hate anything related."

"But math was a logically sound field that made sense to you," Shinobu surmised, finishing for the Water Hashira.

"Indeed. It's like a formalized language, where it's easy to identify contradictions and prove or disprove claims. Also, numbers don't lie," he jested.

"That's quite impressive, Giyuu," Shinobu almost felt like a proud mother hearing her son give an overview of the school day.

"Well, it's not too incredible. Obviously, there's really abstract subtopics such as set theory, cardinalities, metric spaces, measure theory, topology, complex analysis, real analysis, and— Ah, my bad, I went on a tangent," Giyuu quickly comports himself.

"It's alright, Giyuu. I really like it when you get passionate about something; it's a nice change of pace," Shinobu winked.

"Be careful what you ask for, I could go on for hours," Giyuu winked back.

"If you do that, I will make you sit through one of my lectures on the anatomical structure of the human body—I'm quite strict, you know," Shinobu quipped.

"I wouldn't have it any other way," Giyuu smirked.

"Oh, you!" Shinobu laughed.

As on every occasion, the two Hashiras found time to enjoy each other's company, even in the most tenuous of circumstances.

..

..

..

..

Hundreds of years.

How much time has passed, he did not know.

He felt like going mad.

He has been doing nothing but killing for hundreds of years. And to what end? What is he trying to achieve?

Utsuro was but a lost soul in a sea of madness.

Slowly, he concealed himself within human society. Apparently, his outward appearance does not immediately indicate a demonic presence.

However, even as he assimilated himself, he did not let go of the blade.

If he stopped fighting, then he would be useless; all he can do is kill, that's all he knows what to do.

Many have found him useful for their services, especially in war-related matters.

Utsuro quickly learned that the human desire to kill each other carries more blood lust than even the most demonic creatures of hell, especially given how he's a demon himself.

Thus, he continues to slash his foes. This time with legal sanction.

But he still feels hollow.

He's been fighting, killing, and maiming for hundreds of years, but he cannot find the answers to his questions.

He is still lost in this vast red sea, one that is saturated with the blood of his victims, both past and present.

And perhaps the future too.

..

..

..

..

*Splash* *Splash*

The Hashiras were fast approaching their destination.

It was only a matter of time before they faced their greatest foe yet.

Shinobu unexpectedly stopped marching, forcing her partner to comply with this sudden halt in their movements—as their arms were wrapped around each other.

"What is it?" Giyuu inquires, rotating his head in her direction.

"Giyuu... before we go any further... I just want you to know one thing."

Giyuu turned his entire body to face her.

Shinobu continued, "No matter what happens... No matter if we survive this or not... Or if we even survive this war against Kibutsuji Muzan..."

The Water Hashira leaned in closer.

"I will always be glad and grateful for the fact that I met you," the Insect Hashira pulled her head up, staring at her partner eye-to-eye. "Thank you. Thank you for everything."

Giyuu's eyes dilate with surprise, before he finally recomposes himself.

*Tug*

He pulls her in for a hug, embracing her with all the warmth he can provide.

"I'm glad you came with me. I'm glad you're here with me now. I'm glad you're willing to stay with me. You are my light at the end of the tunnel; I will always cherish you now and forever," the Water Hashira spoke with all the emotion, love, and care he could muster.

"I love you, Tomioka Giyuu."

"I love you too, Kocho Shinobu."

With hands clasped together, with their resolve stronger than ever, with their spirits brighter than ever, and with their ardent love for one another everpresent, they proceeded into the darkness.

Into the designated chamber where Utsuro awaited...