Over the past few centuries, Kokushibo had faced no shortage of enemies. Their reactions varied. Some were angry, some were afraid, and some were wary. But among today's opponents, there was one especially remarkable person.
The moment he saw Kokushibo, he smiled brightly and said,
"Long time no see, Aniue."
Kokushibo glanced at the Demon Slayer Corps members standing alert around that person and finally confirmed that he had not come to the wrong place. The other party's reaction was simply unexpected.
Under normal circumstances, no one would call a man with six eyes "Aniue," would they?
"I... have never... seen you."
Hiru paused, then sighed.
"Never seen me, huh... How cold. When you and Muzan came to wipe out the clan, I was the clan leader."
Hearing this, Kokushibo seriously searched his memories. But no matter how hard he tried to recall, he was certain he had never seen the person before him.
"I... have... only... one... younger brother."
Now it was Hiru's turn to doubt himself.
"In that case... do you remember a mother and son coming to your house when you were four or five? The mother should have been Akeno's mother. No, no, a distant younger sister of Lady Akeno."
"I do not recall... However... there was indeed a funeral... held at that time."
After getting his answer, Hiru began muttering under his breath.
"No way. Even if she died hundreds of years ago, isn't that a bit too early? Is this thing messing with me?"
Watching Hiru start muttering to himself again, the Demon Slayer Corps members silently shifted aside and faced off against Kokushibo.
They did not expect Hiru to help. As long as he did not turn around and help the other side, that was good enough.
But just as the two sides were about to clash, Hiru spoke again.
"You at least remember Tsugikuni Yoriichi, right?"
Kokushibo lowered his eyes slightly, unable to understand why this person, who seemed to know him well, would bring up Yoriichi.
"Back then, Muzan was dismembered by Yoriichi-nii in an instant, then got so scared that he split himself into more than eighteen hundred pieces, you know?"
Hiru laughed.
"And Yoriichi-nii slashed nearly eight hundred times in an instant, cutting apart fifteen hundred scattered pieces of flesh. He was only a little short of killing Muzan. At that time, Yoriichi-nii was still human, you know?"
An irritation he had not felt in a long time crawled back into Kokushibo's heart. His hand, which had been resting on his sheath, drew back slightly and rubbed against the hilt. Before he could speak, however, Hiru spoke again.
"I know that little gesture, Aniue. I mean, Yoriichi-nii used to do that whenever he was thinking. Said it made it easier to stay calm?"
Hiru rubbed his chin.
"If you want to surpass Muzan, then at the very least, you'd need to scare him into eighteen hundred pieces in an instant, right? The way you are now, bound by Muzan's blood, you can't possibly surpass him. After all, that coward would never let a demon under him become stronger than he is.
"And Muzan killed the only known person who could learn Moon Breathing. Aniue, aren't you going to do something about that? I know a way to break free of those restraints. Want to try it?"
Kokushibo: ...Is he trying to turn me against him right out in the open?
The Hashira: ...What exactly is this guy trying to do?
Kokushibo and the Hashira silently looked at each other. Then, with perfect tacit agreement, they drew their swords and unanimously decided to ignore Hiru's existence.
"You're ignoring me already? How cruel. But since none of you are paying attention to me..."
Hiru's gaze swept toward the open shoji door behind Kokushibo.
"Then I'll go pay the Infinity Castle a visit, all right?"
Kokushibo slashed toward Hiru almost immediately. But as the blade light passed through, all that came was the sound of shattering crystal. At the same time, Hiru's voice sounded from behind him.
"Look at this fine true gray. What a delightful color~ I wonder if Muzan is in the Infinity Castle right now?"
Tengen looked at the door and house that had been transformed into gray crystal the moment Hiru touched them, then lowered his voice slightly.
"Hey, Kyojuro. Is that the crystal you were talking about?"
"That's right! Though it wasn't this color at the time! It seems Hiru-san can also turn Blood Demon Arts into crystal! I'm not sure whether it works on humans, but he can control these crystals, so everyone, please be careful!"
Kokushibo: ...A troublesome Blood Demon Art.
The corner of Hiru's mouth twitched. After sweeping a glance over Tengen's speechless expression, he said,
"Hey, Kyojuro. Could you keep your voice down when you're plotting? When you say it that loudly, it makes me feel like I'd be letting your words down if I didn't do something to you."
"Is that so! Then I apologize!"
Hiru curled his lip and looked at the gray crystal gradually spreading into the depths of the Infinity Castle. The corner of his mouth lifted into another smile. But this time, before he could say anything, a clear, brilliant blade light slashed straight toward his neck.
Crystal fragments scattered through the air. Hiru staggered back with a hand over the thin line of blood on his neck. Yet his eyes, now completely gray, stared at Kokushibo's body, pierced through by crystal spikes, full of amusement.
"Hey, hey, Aniue. A true samurai doesn't launch surprise attacks, does he?"
Kokushibo's expression did not change. Countless blades abruptly grew from his body, cutting through every crystal spike that had pierced him. Immediately afterward, he swung his sword at Hiru again.
Hiru knew exactly how capable he was in close combat, so he turned without the slightest hesitation and ran into the Infinity Castle. Dense clusters of crystal spikes shot toward Kokushibo one after another.
And just as Hiru expected, after cutting down the spikes, Kokushibo chased after him without hesitation.
As the two of them rushed into the Infinity Castle, the Hashira could not help turning their attention to the jar that had appeared from the doorway alongside Kokushibo not long ago.
After exchanging glances, Tengen was the first to speak.
"This should be that pickle jar Hiru mentioned, right?"
"Are you blind, you bastard?! How dare you call my perfect pot a pickle jar?!"
Seeing Gyokko crawl out of the jar, the Hashira exchanged another glance. In the end, Tengen and Muichiro spoke almost at the same time.
"Sorry, I saw wrong. You're a chamber pot, right?"
"A perfect work? That jar isn't even symmetrical. It's crooked."
Gyokko: ...
Damn it! All of you can die!