Fanficbased on Naruto (by Masashi Kishimoto) and Bleach (by Tite Kubo). This is a fan-made story with no official affiliation. The content is shared as part of the creative rewards on my Patreon.
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Previous chapter:
Mini Renjis running all over the place.
And the risks:
Renji dying alone… extinction of future Mini Renjis… mutant Renji emerging from the sewers—risk level: 80%.
"I'm gonna get you a girlfriend, Renji. Don't worry—I've got this."
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Renji let out a heavy sigh, feeling like he was the center of every uncomfortable stare.
"Come on already, just leave me alone!" he snapped, rubbing his forehead in frustration. "Why am I suddenly the center of all the gossip?"
Killer B, clearly uncomfortable with the direction of the conversation, jumped in quickly, trying to steer things in a different direction with his usual bluntness.
"Yo, yo—what about the meeting? Weren't we here to talk about something serious?"
The Raikage's expression turned stern again as he gave a small nod.
"You're right, B. But first, I want to assign a special mission." He turned his gaze toward Yoruichi, whose curious eyes were locked on him. "Yoruichi, I'm giving you an S-rank mission—probably the hardest of your career: find Renji a girlfriend. Will you accept?"
Yoruichi's eyes lit up with barely contained excitement. After weeks of inactivity, stuck in a child's body with nothing to do, the idea of a mission—ridiculous as it was—was exactly what she needed.
Without hesitation, she dropped dramatically to one knee and raised her arm like she was taking an oath.
"I accept the mission, Raikage-sama! I won't fail!"
She tried to make a flashy exit using body flicker, only to remember she still couldn't use that jutsu. Improvising, she tossed a small homemade smoke bomb and sprinted down the hallway on her toes.
Everyone tried to hold in their laughter, though Killer B couldn't resist and followed her to keep an eye on things.
Renji stood frozen, awkwardly laughing while the stares started to fall back on him.
"Okay, now why are you all still looking at me?"
The Raikage pointed at him without hesitation, his tone cutting through the room.
"Renji, you have a mission too: follow the kids. Don't come back until there's progress."
"But Raikage-sama...!" Renji began to protest, incredulous.
One firm look was all it took to silence him. With a resigned sigh, he turned on his heel and headed out after them, closing the door behind him.
Once they were alone, the Raikage settled back into his chair and turned to Denji.
"Good. Now that only the people who matter are here—what was that urgent thing you needed to share?"
Denji stood up, carrying a stack of notes, diagrams, and charts.
"It's about my daughter's brain. There's something... unusual."
A-JR raised an eyebrow, intrigued.
"Your daughter's brain? What's so unusual about it?"
Denji nodded and began spreading the papers across the table.
"It's extraordinary. Her neurological development is far beyond what we'd expect for her age. But that's not all. We believe her brain has undergone a kind of forced adaptation—like it was pushed past its natural limits."
The Raikage looked at him with renewed focus.
"Adaptation? Explain."
"Yes. According to the studies Yuna conducted, her brain seems to have evolved under unknown circumstances that forced her to surpass her own limits. These are the main characteristics we've found:
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Report on Yoruichi's Brain Development
Author: Denji And Yuna
Subject: Analysis of Advanced Neurological Features and Their Implications
Summary:
Yoruichi displays a neurological profile that falls well outside the parameters of normal human development—even among highly trained individuals. Her brain exhibits a combination of traits typically seen in advanced adult cognitive stages, with performance levels in some areas exceeding known records. This points to an extreme case of forced neuroadaptation.
Key Features
1. Balanced Cerebral Hemispheres
Function: Neural activity is evenly distributed between both hemispheres, allowing her to blend analytical logic with creative thinking seamlessly.
Potential Consequences:
Advantages:
High adaptability in complex scenarios requiring both logic and creativity
Innovative problem-solving approaches
Risks:
Tendency to overanalyze every aspect of reality, which may slow down decision-making in emergencies
Risk of "analysis paralysis," where evaluating every variable takes longer than the situation allows
2. Extreme Neuroplasticity
Function: Her brain forms new neural connections at an abnormally high speed and can restructure existing ones with ease.
Potential Consequences:
Advantages:
Accelerated learning and rapid acquisition of complex skills
Greater mental resilience in the face of trauma, thanks to rapid adjustment to new conditions
Risks:
Potential for obsessive behavior, as the constant pursuit of new challenges, may become a compulsive need
Susceptibility to sensory overload without adequate rest periods
3. Hyperintense Myelination
Function: The axons in her nervous system are coated with an unusually dense layer of myelin, drastically boosting synaptic transmission speed.
Potential Consequences:
Advantages:
Near-instantaneous reactions to external stimuli, highly beneficial in combat or high-pressure situations
Competitive edge in tasks requiring fast processing, such as rapid strategy or complex calculations
Risks:
High energy consumption; prone to neurological fatigue if unregulated
Difficulty adjusting to environments that require slowing down, potentially causing frustration or impatience
4. Advanced Information Processing
Function: Able to filter, organize, and store data with extreme efficiency.
Potential Consequences:
Advantages:
Excellent focus on relevant information, minimizing distractions in critical tasks
Lower stress levels when handling large volumes of input
Risks:
Possible emotional detachment, as less "relevant" human interactions may be filtered out
Emotional wear in personal relationships, prioritizing logic over empathy
Struggles to relate to individuals with slower mental rhythms
Psychological and Physiological Implications
Sudden Mood Swings
Peaks in brain activity can disrupt emotional balance, leading to bursts of enthusiasm or apathy without a clear cause.
Chronic Insomnia Due to Neural Hyperactivity
Her mind remains active even at rest, impairing sleep and potentially reducing long-term performance if left unchecked.
Risk of Emotional Detachment
Excessive logic in decision-making may lead her to devalue personal bonds, functioning more like a results-driven machine than a human being.
Collapse from Overload
Although she can process vast amounts of information, the system has limits. Without adequate rest, she may experience temporary memory lapses, emotional shutdowns, or anxiety episodes.
Constant Need for Intellectual Stimulation
Without challenges, she experiences severe boredom, which may trigger impulsive, reckless, or erratic behavior.
Initial Recommendations
Guided meditation and impulse control: Daily training to stabilize brain activity
Balanced stimulation: Constant but measured challenges to avoid burnout
Emotional training: Activities that promote empathy, patience, and frustration tolerance
Mandatory rest routines: Non-negotiable rest periods tied to art, music, or nature exposure
Regular neurological monitoring: Monthly scans and evaluations to detect early signs of overload
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Denji paused, letting the data sink in for everyone present. Then, he looked up.
"This is what we know so far," he said, his voice deep but restrained. "But her evolution hasn't stopped. In fact, it's likely we're only seeing the tip of the iceberg. Her development is ongoing, and if we're not careful, what now seems like a gift could become a burden. We have to guide her precisely—not just to unlock her abilities, but to protect her from them."
The Raikage nodded slowly, thoughtfully. He brought a hand to his chin, tapping his fingers in a quiet rhythm as he processed the information.
"It's fascinating… but also deeply concerning. We're not just dealing with talent here—this could be a potential anomaly. We need to make sure she receives the right kind of support: physical, emotional, and tactical." He paused. "How advanced is her sensory processing? Can she already read her surroundings beyond visual input?"
Denji nodded, crossing his arms.
"It's remarkable. The first time I tried testing her reflexes, I used Body Flicker. She didn't follow me with her eyes… but the moment I stopped moving, even with just the faintest sound, she locked onto me instantly. She didn't look—she sensed me, directly."
The Raikage raised his brows, intrigued.
"You're saying her other senses are just as developed?"
"Yes," Denji confirmed. "When I asked her how she found me, she said it was two things: the subtle sound of my movement… and my scent."
"Her sense of smell too?" said the Raikage, raising an eyebrow. He couldn't help but recall how Yoruichi sometimes curled up like a cat or made feline-like expressions when she was comfortable—or bored.
Denji gave a faint smile, clearly thinking the same.
"Yeah. Her sense of smell is incredibly sharp. She can recognize me by scent even when I'm out of sight. The only limit is that if I move too fast, the scent trail doesn't follow fast enough. But the moment I stop, she finds me immediately."
The Raikage let out a low whistle, impressed.
"So we're talking about someone who, without formal sensory training, already shows capabilities on par with several clans. Would you say it's like… a convergence of mental abilities?"
Denji nodded firmly.
"Exactly. She exhibits traits similar to the Inuzuka's sense of smell, the Uchiha's refined visual perception—though without a dōjutsu—and the mental speed of a Yamanaka. But the key difference is that, in her case, all of it is happening without genetic enhancements or inherited techniques. It's her brain doing all the work."
A-JR, who had remained silent until then, sat up slightly in his seat, clearly surprised.
"So it's like she has some kind of base version of all those abilities—still unrefined, but already active…"
"Yes," Denji replied, serious. "And once she begins channeling chakra regularly, her affinity with Yin release is going to skyrocket. Her brain is perfectly suited to manipulate that kind of energy. In fact, I'd say she's almost exclusively geared toward it."
The Raikage crossed his arms, a faint, reflective smile forming on his face.
Kumogakure... our tradition is to hone the body to its limit. We train in kenjutsu, taijutsu, speed, and strength. We're close-range shinobi. But Yoruichi... she's built differently. She's mind, not muscle. Yin, not Yang. Spirit, not flesh…
Denji gave a small nod of agreement, but his expression quickly turned serious again.
"Yes. While here the body is trained as the primary weapon, in her case, development has been almost entirely mental. Her evolution leans toward Yin. That makes her powerful… but also vulnerable."
A.JR frowned, thoughtful, recalling how his father always warned him that pushing physical development to the extreme wasn't necessarily a good thing.
"Like our father used to say—having extreme physical development isn't always a good thing. I guess the same goes for the mind."
Denji looked directly at the Raikage, knowing he would instantly grasp the deeper meaning behind what he was about to say. The Raikage answered for him.
"An excess of Yang energy, without the counterbalance of Yin, can lead to a dangerous imbalance. A jinchūriki with a purely Yang-tailed beast, for example, could become physically unstoppable… but their chakra control would fall apart. The brain couldn't keep up with the body. A genius would turn clumsy, and an average person could end up acting almost… idiotic."
A.JR nodded solemnly, understanding the scale of the imbalance Denji was warning about.
"And if there's too much Yin energy instead…" he added, completing the thought, "the body weakens. It can lead to physical illness, muscle loss, and constant fatigue. If her brain keeps evolving at this rate, her body won't be able to keep up."
Denji nodded, this time more gravely.
"Exactly. Yoruichi is walking a razor-thin line. Right now she's in balance… but it's an unstable one."
"Can it be corrected?" A.JR asked, clearly concerned.
"Yes," Denji replied, turning to him. "And honestly, it's easier than it sounds. She just needs physical training. Nothing extreme—just enough to strengthen her Yang energy and maintain the balance with Yin."
The Raikage watched him closely.
"And?"
"And," Denji said with firm resolve, "I need you to teach her the Lightning Method."
The atmosphere grew tense.
"That training is too intense for someone without prior conditioning," A.JR said, uncertainty in his voice.
Denji shook his head gently.
"I know. But I also know it's the best path. I don't want to turn her into a combat beast—just give her the physical foundation she needs to sustain her mental growth. The Lightning Method reinforces the nervous system, strengthens the muscles, and trains the body to endure a constant flow of chakra. It's the only way to stop her Yin from consuming her from the inside."
The Raikage fell silent, pensive. He knew exactly what it meant to share that method.
The Lightning Method wasn't just a physical regimen. It was a clan technique, refined over generations. It allowed the body to reach a physical state comparable to the First Gate of the Eight Gates but without the self-damaging strain. Its practice strengthened the body's electrical impulses, preparing it for high-speed techniques and to withstand Raiton Chakra Mode—the Raikage's signature.
To share it… was a high-level decision.
After a long pause, the Raikage sighed and spoke.
"Alright. I'll allow it."
Denji stared at him, surprised.
"Seriously?"
Without hesitation, he stepped forward and gave a deep 90-degree bow, voice filled with gratitude.
"Thank you so much, Raikage-sama!"
The Raikage raised a hand to wave it off.
"No need for that. I'm doing it for her… and because I trust you."
But Denji didn't rise immediately. He knew exactly what that meant: the Raikage was willing to share a lineage technique with a girl who wasn't even born into the clan.
When he finally looked up, he heard the Raikage continue:
"You know, Denji… I've actually thought about teaching Yoruichi my technique for a while now."
Denji looked at him in surprise.
"What do you mean?"
"I can feel it. Your daughter has a natural affinity for Raiton. She doesn't even use chakra yet, and it's already noticeable."
Silence filled the room.
"Nature energy dances around her," the Raikage added.
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End of Chapter 10
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[For those wondering how they know so much about the brain—just remember: in this world, there are living volunteers willing to die for science...]
Author's Note:
I chose to end the chapter with this revelation about the Raikage and his sensitivity to natural energy. It's not random. While not directly tied to the Third Raikage in canon, it's still rooted in the universe's lore.
As for the brain development concept—that's something I've carried for years. It came from a question that always stuck with me: How do reincarnated characters survive with an infant's brain? Realistically, a baby's brain couldn't handle the overload of memories; it would probably collapse. In this story, Astra's brain adapted to keep pace with her memories—because otherwise, she wouldn't survive.
And to the readers who think she's already overpowered:
You truly have no idea of the scale of the story I'm planning.