"Then is there a possibility… that a demon could retain its source blood while offering the blood gained through feeding and accumulation to the Demon King?"
At Ubuyashiki's words, both Hiru and Yoriichi froze.
"You mean Kokushibo gave his blood to Muzan?" Hiru frowned. "But blood is directly tied to strength. He shouldn't do something like that… especially given his obsession with power."
"I'm only asking whether such a possibility exists," Ubuyashiki said, his brow furrowing. "As Hiru mentioned earlier, Kokushibo is a demon capable of breaking free from bonds. If he can do that, then perhaps blood is no longer essential to him."
Hiru's frown deepened. After a long silence, he finally looked at Yoriichi.
"Brother… can you separate your blood?"
Yoriichi closed his eyes. After a brief moment, he nodded slightly.
"I can."
"How much?"
"If I do it right now, about one-tenth. To separate all of it without affecting my strength would take time."
"Could it be that Kokushibo struck some kind of deal with Muzan after breaking free?" Hiru muttered, his expression heavy with confusion. "That doesn't make sense… any deal between them shouldn't involve me. I can't beat anyone—there's no reason to make me the centerpiece of it all…"
Yoriichi watched him silently. In his hand, a sphere of blood formed, roughly the size of an adult man's fist.
"Come to think of it, I hadn't considered this before," Yoriichi said. "Hiru, you've been expending a great deal lately, haven't you? Take this blood. It will help you recover faster and give you more assurance when facing Muzan and Kokushibo."
"Will you be all right, brother?"
"Yes. It won't affect me," Yoriichi replied as he watched Hiru take the blood sphere. "I'll gradually separate more blood for you later. To do so while continuing to grow stronger will probably take one or two years. As for the source blood… separating that would take even longer, and since I need it to locate you, I won't touch that part."
Hiru stared at the blood sphere with a deeply aggrieved expression.
"Hey, brother. I was the one who turned you into a demon, right?"
"That's right."
"Then why is it that you don't weaken when you separate blood, but I do?"
Yoriichi pondered seriously for a moment.
"Perhaps… because I don't rely on blood to grow stronger?"
Hiru went blank for two full seconds. Then, without another word, he absorbed the blood into his body and began refining it.
Watching the brothers' exchange, Ubuyashiki couldn't help but laugh.
"You two truly have a close bond."
Yoriichi looked at Hiru, who was concentrating on absorbing the blood, and smiled.
"Yes. I'm very fortunate that Hiru is my younger brother."
"If you don't mind, Yoriichi-sama, could you tell me about your early experiences?"
"Of course. Though I left home rather early, so there are things I don't know in full."
"Please, only share what you feel is appropriate."
As Yoriichi spoke, Ubuyashiki gradually came to understand more of their past, and his thoughts began to take clearer shape.
"So it was Hiru who overcame sunlight?"
"Yes," Yoriichi said. "Hiru is remarkable. If he hadn't come to our family, perhaps he could have carved out his own path and lived a healthy, peaceful life to its natural end."
He turned his gaze to Hiru again, his expression gentle.
"But I'm also grateful that he became my brother. After Uta's death, the destruction of our family, and my elder brother becoming a demon, Hiru was the only thing that kept me going."
"Even so, I sometimes feel guilty for my weakness… and for achieving nothing."
"You are far too self-critical," Ubuyashiki said, shaking his head. "If you are someone who achieved nothing, then what does that make the rest of us?"
"My abilities were a gift from heaven," Yoriichi said softly, lowering his eyes. "Yet I failed to use that power to protect anything. In the end, I even broke the vow I made after Uta died, choosing to live on as a demon. Someone as unworthy as me—how could I deserve your praise?"
"Brother, you really should dial back your world-weariness a bit," Hiru said as he opened his eyes. "I honestly can't listen to this anymore."
Yoriichi smiled and let the topic pass.
"So? Is the blood fully absorbed?"
"Yes. The quantity is less than mine, but the quality is extremely high, and it carries a warm, comforting sensation," Hiru said, clenching his fist. "My condition right now is as good as when I first left the mountain. Most importantly… my stomach finally isn't hungry anymore."
"That's good," Yoriichi said, reaching out to ruffle Hiru's hair. "I can rest a little easier now."
Ubuyashiki heard Hiru mutter something under his breath, though it was too quiet to make out. Yoriichi's smile, however, grew even gentler.
[Perhaps my worries were unnecessary after all.]
Ubuyashiki smiled faintly to himself.
"Ah, right. This is for you."
Ubuyashiki accepted the medicine pouch Hiru handed over, his expression puzzled.
"Is this something I'm supposed to take?"
"No. It's for you to use against us."
Ubuyashiki: …?
"Is this the same medicine that left me weakened for three days last time?" Yoriichi frowned. After Hiru nodded, he seemed to recall something unpleasant, but his expression soon relaxed again. "Mm. Giving it to Oyakata-sama is indeed a good choice."
Holding the medicine pouch, Ubuyashiki stiffened completely.
"T-this is…"
"Just like I said—something for you to use to ambush us," Hiru said casually. "You know how unpredictable demons can be. Who's to say we won't change our minds after killing Muzan? It never hurts to keep a backup plan."
Ubuyashiki: ...
"You weren't seriously thinking of trusting us completely just now, were you?" Hiru frowned at the silent Ubuyashiki. "Never trust demons. Do you understand? Even if they don't show hostility, you must stay alert. Keep your guard up."
Yoriichi nodded calmly.
"That's right. If things ultimately spiral out of control, we'll have to rely on you, Oyakata-sama, to find a way to kill the two of us."
Hiru glanced at Ubuyashiki, who had begun clutching his stomach again.
"Another stomachache? Didn't I have Mikazuki help adjust your diet? There was nothing wrong when I took your pulse earlier."
Ubuyashiki was silent for a moment.
"It's nothing—just my own issue. But Hiru, don't you find it strange to say such things given your current position?"
"No," Hiru replied evenly. "In the end, demons are beings that shouldn't exist. If I hadn't overcome wisteria and then unexpectedly overcome sunlight, I would have killed myself back then. Demons are pitiful creatures, unworthy even of redemption."
Ubuyashiki lowered his hand, his expression filled with confusion.
"Why do you think that?"
"Because demons find it difficult to empathize with human emotions," Hiru said, lowering his gaze. "And in the initial stages of becoming a demon, it's hard for them to retain their reason. In that state, they may not even understand what they've done. Even if they later regain clarity and recall their lives as humans, those memories no longer stir anything within them."
"In other words, those memories are nothing more than scenes they can't truly place themselves into. For such pitiful beings… should they even be allowed to exist?"