The moment Yamada shifted his stance, Ichirō's eyes changed. All trace of emotion vanished, and every muscle in his body tightened like drawn steel.
Whoosh!
In one swift step, Ichirō lunged forward — his fist driving straight toward Yamada's face.
'That look… what's with those eyes? And that power—!' Yamada thought, shocked by the sudden surge of killing intent. The man before him felt entirely different from the student who had been quietly standing there moments ago.
But because of that, Yamada grew even more cautious. People like this — the ones who could suppress all emotion — were the most dangerous of all.
---
Absolute Rationality — a state of self-induced hypnosis Ichirō had once developed during his years as a State Alchemist.
It was a forbidden mental technique drawn from the darkest corners of alchemical knowledge.
Entering this state meant attaining pure, unclouded logic. The user retained only a single driving thought — one objective — and every other emotion, person, or consideration became irrelevant. Because of this, some called it the One Thought State.
It was both a blessing and a curse. History held many accounts of those who, under the influence of similar forbidden arts, completed missions flawlessly but ended up slaughtering friends, family — or themselves — in the process.
A forbidden art among forbidden arts.
And yet, the reason this technique was never truly erased was simple—
It was terrifyingly effective.
---
The human body typically uses only thirty to forty percent of its muscular potential; exceeding that limit risks tearing tendons and shattering bones. Through proper training, this ratio could be improved slightly — but only slightly.
Absolute Rationality removed that limiter entirely.
The user could unleash 100% of their body's physical strength.
For alchemists proficient in Flesh Transmutation (focused solely on the body), it was a perfect match.
Ichirō had never specialized in that field, but he'd found a workaround: in this world, he could reinforce his body using spiritual energy as a buffer. It wouldn't last long — but long enough.
—
Shhk!
Yamada blocked Ichirō's right punch — but the moment contact was made, Ichirō's left hand flashed like a blade. His knife-hand strike sliced cleanly through Yamada's shihakushō, leaving a tear across the chest and exposing the white underlayer beneath.
Yamada barely had time to react before Ichirō's next attack came. Twisting his body in a fluid spin, Ichirō drove his right elbow forward with crushing momentum.
"Good follow-through," Yamada noted instinctively. "But your motion's too wide—"
Crack!
His words died in his throat as a sharp snap echoed through the room. His expression froze, and he instantly flash-stepped backward, clutching his trembling right forearm.
Fractured.
The bone in his lower arm had cracked from the impact.
"Did… did I see that right? Did Yamada-sensei just—get injured?"
"No way… he's joking, right? A first-year student injured a teacher?!"
"..."
Yoruichi and Urahara both stared, eyes narrowing in disbelief.
"That technique…" Urahara muttered, frowning.
Yoruichi nodded. "He focused his reiryoku into a single point at his elbow — maximizing destructive force. That knife-hand earlier, and the follow-up he didn't even finish… they're all lethal combat techniques. Designed for killing."
Her voice carried both surprise and respect.
Those moves were even more vicious than the Shihōin clan's secret Hakuda forms — pure offense, using one's own body as a weapon, utterly disregarding self-preservation.
Yamada understood it too. Frowning, he immediately raised a hand to stop the spar. Not because of his own injury — his skill wasn't so low that a student could truly harm him if he had been serious.
He was worried about Ichirō.
With the strain he was putting on his body, continuing the fight could cause irreversible damage.
...
As soon as Yamada's order reached him, Ichirō's gaze softened. Emotion seeped back into his expression. Reason relinquished its hold to feeling once more.
Seeing the teacher's trembling arm, Ichirō's heart sank. He bowed deeply, a full ninety degrees.
"Sensei, I'm sorry! I didn't mean to!"
Yamada shook his head. "I'm fine. But do you realize how dangerous your combat style is? Spiritual energy isn't a cure-all. You can endure the strain now, but someday your body won't."
Ichirō forced a smile. "Don't worry, Sensei. I know my limits."
Yamada studied him quietly, then sighed. "Alright. Just… be careful. You're dismissed."
He turned and left the dojo, hiding the pain in his arm. A fight against someone in that state — someone who had entered true Absolute Rationality — was not something one escaped unscathed from.
"Are you alright?" Urahara and Yoruichi approached him as Yamada left.
Ichirō nodded. "Yeah, don't worry. The state wasn't complete, and my reiryoku shielded most of the damage."
"Good," Urahara grinned. "Come on — time for lunch."
"Mm."
In truth, Ichirō wasn't fine. Every muscle in his body was screaming. Microtears burned beneath his skin.
Under Absolute Rationality, every ounce of his physical power had been unleashed — and every strike, no matter how effective, exacted a toll. His spiritual energy hadn't been enough to fully protect him.
In his previous life, this hadn't been an issue. He'd mastered Iron Transmutation, and after becoming a State Alchemist, he'd even delved into limited Body Transmutation. Combined, they allowed him to temporarily achieve the legendary "Iron Body" — a defense so durable it could withstand the harshest of military martial arts.
But here, in the Soul Society, he was far from that level. Not only could he no longer perform human transmutation — he couldn't even refine ordinary metal.
The problem lay in the nature of this world:
everything in the Soul Society was made of reishi, not matter.
His old transmutation circles were useless here. He would need to rewrite them from scratch.
For an alchemist, the transmutation circle was the foundation of every technique — each material, each practitioner required their own unique formula.
In other words, Ichirō's alchemy had evolved into something entirely new — Reishi Alchemy.
To reconstruct his "Iron Body," he'd need to incorporate reishi-based formulas into the equation.
The difficulty of that task had increased exponentially.
Still, it was necessary.
---
The Soul Society's power ceiling was far higher than the world of alchemists — and that meant his fighting style could reach new heights as well.
All he had to do was merge the two worlds' principles:
the science of alchemy and the spiritual power of a Shinigami.
When that day came, he was certain his strength would transcend both worlds.
But one thing was clear — he could never again open a fight in Absolute Rationality.
The toll was too great.
Ahead of him, Urahara and Yoruichi exchanged a glance. Seeing Ichirō's occasional twitch of pain, they said nothing. If he didn't want to talk about it, they wouldn't pry.
---
The Next Day
The first swordsmanship class brought Ichirō a pleasant surprise —
Asauchi had been issued.
The Asauchi — the nameless Zanpakutō forged by Ōetsu Nimaiya, the Blade God — formed the very foundation of Shinigami power. It was the blank from which every Zanpakutō was born.
Among all the arts of the Shinigami, nothing captured the imagination quite like the Zanpakutō — elegant, lethal, and deeply personal.
Ichirō had heard of them during his decades in Rukongai, but they were impossibly rare outside Seireitei, especially in the stable districts. To receive one this early in the term was beyond his expectations.
The reason was simple: the Academy wanted its students to bond with their blades as soon as possible.
Even if they couldn't awaken the sword's true name, there was always a chance.
Because somewhere among these new recruits, there might be one whose soul resonated powerfully enough—
to awaken their Zanpakutō ahead of all others.
Whether they caught such a prodigy or not was secondary.
After all—before you can catch fish, you first have to cast the net.