Hiru retreated swiftly, watching as Akaza fixed a grave stare toward the area slightly behind him. He straightened his chest.
"Stunned, huh? We've got reinforcements!"
But the moment the words left his mouth, Hiru realized Akaza was looking at him the same way one would look at an idiot.
That all-too-obvious look made Hiru uneasy. Yet he didn't turn around to confirm it. He hadn't sensed anyone approaching, and there were very few people capable of unleashing a slash that powerful—his brother among them. More importantly, aside from his brother, no one would come to save him.
So yes. Right now, he should still be the one tying Akaza down.
Just as Hiru prepared to rush forward again, a hand settled on his shoulder, effortlessly suppressing his movement. A familiar voice came from behind him.
"Don't go."
"Why? Brother—" Hiru turned around, then froze. "…Brother?"
"Unexpected."
The newcomer's appearance was nearly identical to Tsugikuni Yoriichi's, except that along the right side of his face and neck spread an additional flame-like mark. He slightly lowered his head, looking down at Hiru. "You still call me that?"
Rengoku, who had charged after them, froze as well. The shock, fury, and grief from moments before had not yet faded, and combined with his current blankness, made his expression look almost comical.
Rengoku was one of the few within the Demon Slayer Corps who had seen Yoriichi's true face. The young man standing beside Hiru, dressed in a purple snake-patterned kimono, appeared only slightly older than Yoriichi, with over ninety percent similarity in their features.
Rengoku was certain that if Yoriichi dyed his hair black and aged a few more years, he would look exactly like the man before him. And yet, everything about this man screamed danger to his instincts.
There was no doubt about it—this youth, who looked almost identical to Yoriichi, was a demon. And an extremely powerful one.
[But…] Rengoku's gaze shifted to the stunned Hiru.
[I've never heard of Hiru having an older brother. No—Gyomei and Urokodaki did mention something… But this strong?]
"So the traitor shows himself at last." Akaza's gaze locked onto the man, fists clenched. "Is this frail little brat the reason you betrayed the Lord?"
"I've already spoken with Muzan," Kokushibo withdrew his hand, his eyes calmly meeting Akaza's. "It seems we failed to reach an agreement."
"You despicable traitor!" Veins bulged across Akaza's face. "It was the Lord who gave you the chance to live, and yet you betrayed him! Can someone like you still call himself a warrior?!"
"It is precisely because I acknowledge his favor that I repeatedly chose restraint." Kokushibo lowered his eyes. "This is my final warning. Convey it to Muzan: before I achieve my objective, do not interfere again. Do not attempt anything further. Next time, I will not hold back."
"You—"
[Akaza, return.]
The voice echoing from the depths of his mind halted Akaza mid-charge. He glared at Kokushibo with hatred.
"You shameless traitor… Next time we meet, I'll crush your skull."
Kokushibo watched as an ornate paper sliding door manifested out of thin air behind Akaza.
"I'll be waiting. But you won't have any chance of winning."
Akaza clenched his teeth, shot Kokushibo one last look, and stepped through the door. As it closed, his figure vanished from the battlefield.
The forest fell into a heavier silence.
Rengoku kept gesturing urgently, signaling for Hiru to leave Kokushibo's side, but Hiru never looked away. From beginning to end, his eyes remained fixed on Kokushibo.
After Akaza's departure, Kokushibo stood quietly in place, head lowered, gazing down at Hiru.
Rengoku couldn't even find an opening to intervene—let alone pull Hiru away.
After an unknown stretch of silence, Hiru finally spoke, his voice hoarse.
"How dare you do this…"
Kokushibo remained motionless, offering no response.
That very calmness seemed to snap something inside Hiru.
Under Rengoku's horrified gaze, Hiru reached out, seized Kokushibo by the collar, and yanked him close, shouting in accusation.
"How dare you appear like this! What right do you have to show yourself with that face! Don't you feel even a shred of shame for what you've done?!"
Rengoku gripped his sword hilt tightly and moved closer, step by careful step. He didn't understand the full situation, but judging by how Akaza had been driven off with mere words, they were clearly no match.
He could only hope to find a chance to save Hiru.
Kokushibo glanced once at Rengoku, who was quietly repositioning himself, then lowered his gaze to the hand clutching his collar. After a long silence, he finally looked Hiru in the eyes.
"Why are you angry?"
"You ask me why I'm angry?!" Hiru bared his teeth, his voice turning sharp. "You abandoned your wife and child for that so-called pursuit of strength! You destroyed our clan! You betrayed your vows! And you dare ask me why I'm angry?!"
Rengoku could clearly see Hiru trembling from head to toe. His eyes were red, his fury reaching its peak—yet his expression was one of such profound sorrow that he couldn't even cry.
Kokushibo, by contrast, remained utterly calm, not a single ripple of emotion crossing his face.
Kokushibo lowered his eyes, reached out, and grasped Hiru's wrist, forcing him to release his grip.
"In what capacity are you questioning me?"
"…What capacity?" Hiru shook his hand free. After a brief moment of stunned silence, his anger surged even higher. "At a time like this, you still ask what capacity?! I'm questioning you as the head of the Tsugikuni family!
You chose to leave the family to grow stronger—I can understand that! I can even understand your resentment at being surpassed by your younger brother, and your growing distance from him! But how could you ever answer to a family that loved you and trusted you?!"
Kokushibo lowered his gaze, looking down at the enraged Hiru in silence.
"After you left, I could learn things I'd never touched before. I could even go to my death calmly, out of gratitude for being raised—so long as it supported the family!
So Mother wouldn't be disappointed. So you'd have no worries. So my brother wouldn't lose his place to return to! Otherwise, why would I protect a clan that only taught me to sacrifice for others, a clan that wouldn't even record my name?!"
Hiru roared, fists clenched.
"But what did you do?!
You abandoned everything! You slaughtered our kin and devoured their bodies! Do you know what I thought when I saw those mutilated corpses?!
I wondered why the brother I had always respected and trusted had become that monster! I wondered whether I'd failed Mother's expectations! I wondered whether we had no home left from that point on! I even wondered why you didn't kill me—why you left me behind to face that hellish sight alone!
After becoming a demon, did you ever feel even a moment of remorse for those who trusted you completely—who believed you would return to lead them, only to be slaughtered and devoured by you?!
You threw everything away, so why do you still wear that face?! How shameless do you intend to be, with not a trace of repentance?!
Kokushibo—answer me! Say something!"
"…As you said, from the moment I stepped out of that house, there has only ever been Kokushibo in this world. Tsugikuni Michikatsu no longer exists."
Kokushibo's hand tightened unconsciously around the scabbard, yet he merely lowered his gaze calmly, looking at Hiru, whose eyes were split wide with fury.
"I am only using my original appearance again."
[Tsugikuni? Is that his and Yoriichi's surname? I've never heard that name before…]
Rengoku paused in his advance and glanced at the enraged Hiru.
[And would a large clan really appoint someone so young as its head?]
While Rengoku was still puzzling over this, Hiru suddenly shouted and lunged toward Kokushibo.
Rengoku suppressed his thoughts and was about to move in to assist—but the sudden clash had already ended.
Kokushibo remained standing where he was. His long blade had been drawn, forcing Hiru to his knees before piercing straight through his right shoulder, pinning him firmly to the tree trunk behind him.
Yet Hiru seemed utterly unaware of the pain. Both hands clamped tightly around the blade as he glared viciously at Kokushibo.
"Didn't you say that if we ever met again, you'd kill me on the spot?! Come on! Kill me! Why aren't you doing it?! Who are you trying to put on a show for by holding back now?!"
"…Not yet." Veins rose along the back of Kokushibo's hand, his voice slowing further. "I still need you to witness certain things."
"Witness?"
Hiru could feel the crimson blade devouring his flesh, but the pain did nothing to quell the rage burning in his chest. "Haven't I witnessed enough already?! Just how far do you intend to trample the name of the Tsugikuni clan before you're satisfied?!"
"I have never—"
"Breath of Flame, Fifth Form: Flame Tiger!"
Kokushibo withdrew his blade and narrowly evaded the roaring vortex of flames that surged forward like a ferocious tiger. He frowned and looked at Rengoku, who had positioned himself in front of Hiru.
"…Utterly lacking in decorum."
Rengoku raised his voice without hesitation.
"I see no reason to show you any decorum! And I've never heard of holding a conversation while leaving your sword stuck in someone's body!"
Kokushibo tightened his grip on the blade, thick white vapor spilling from his mouth.
"The ravings of the weak…"
"Rengoku-san, please leave…"
Hiru remained slumped against the tree, blood continuing to pour from his chest wound. His breathing was unsteady, but his voice had lowered considerably. "This is a matter between brothers."
"As a senior, how could I abandon my junior and flee on my own in a situation like this?"
Rengoku kept his eyes locked on Kokushibo's movements, standing firmly in front of Hiru. "How is it? Can you still stand? If we hold out together until dawn, it should be manageable. We—"
"I said—get away!"
Rengoku instinctively turned his head, only to meet a pair of gray-tinged eyes staring straight at him, marked by strange cross-shaped pupils.
In that instant, it felt as though he had been plunged into the depths of winter.
"Hiru, you—"
Hiru lowered his gaze, his voice dropping even further.
"…Please leave."
Rengoku's eyes fell on the wound in Hiru's right shoulder. After a brief silence, he tightened his grip on his sword and turned back toward Kokushibo.
"Endure it, Hiru. Do not lose to your own desires. I will guard you here until dawn. I swear by the name of the Flame Hashira—I will not allow you to die as a demon, nor will I let this man take you away."
Hiru: …?
[What is he talking about? He doesn't think I was turned into a demon by Kokushibo and am suppressing the urge to eat people, does he?]
Hiru's emotions instantly short-circuited.
[He doesn't actually think I turned Hiru into a demon, does he? He never suspected it at all?]
Kokushibo's hand on the hilt trembled as well.
[The Rengoku family truly hasn't changed in hundreds of years—still this blunt.]
The hostile brothers found their thoughts unexpectedly aligned.
The confrontation that had been on the verge of erupting was, surprisingly, subdued by a single sentence from Rengoku.
The awkward silence didn't last long.
Measured footsteps approached from afar, and a white-haired swordsman wearing a mask emerged from the forest.
"Rengoku-san, please leave."
"Yoriichi!"
Rengoku brightened at the arrival of powerful reinforcements. "I'll stay and support you! And Hiru—"
"Please leave. This is a matter between us brothers."
Yoriichi removed his mask. "Leave it to me."
"But Hiru was—"
"I will handle it."
As he passed Hiru, Yoriichi placed the mask over his head and lowered his gaze.
"I'm sorry I came so late."
Hiru raised a hand to steady the mask, saying nothing.
Rengoku tried one last time. "But Yoriichi, I—"
"Rengoku-san," Yoriichi said softly. "Please don't ask any further."
Seeing the sorrow on Yoriichi's face, Rengoku finally lowered his sword.
"…I understand. I'll wait for you at the Wisteria House. Please make sure you return."
No reply came.
Rengoku only saw Yoriichi staring intently in Kokushibo's direction, veins bulging on the hand gripping his scabbard. Nearby, Hiru sat silently against the tree, mask pressed to his face, his expression hidden.
Rengoku knew this was no longer a situation he could—or should—take part in. Beyond offering prayers and blessings, there was nothing he could do.
After engraving Kokushibo's appearance firmly into his memory, Rengoku withdrew swiftly, remaining vigilant.
…
Once Rengoku had gone, Yoriichi finally broke the silence.
"It has been a long time, elder brother."
"…So you're still alive."
Kokushibo had recovered from his initial shock, though the tight grip on his scabbard betrayed his inner unrest. "That truly was unexpected."
"…Yes."
Yoriichi lowered his head. "Because of my own incompetence, I chose to become a demon."
"Even now, you still say such things…"
Kokushibo raised his long blade. "Tsugikuni Yoriichi—you are as revolting as ever."
Yoriichi did not respond. He simply raised his own sword.
In an instant, the two collided.
The earth and trees around them were torn free and hurled aside as blazing flames and razor-sharp crescent arcs intertwined, erupting with terrifying force.
Hiru raised his arm to shield himself from the flying debris. He stared blankly at the two sword forms as they merged and tore at one another.
After a long moment, he sat quietly in place, leaning against the tree, calmly watching the battlefield in silence.
No matter the outcome, he would witness it, record it, and accept it.