Ren knew that checking himself for genjutsu was not a perfect safeguard.
If Orochimaru's skill with illusions had reached an overwhelming level and he had deliberately manipulated Ren's senses, Ren might never notice anything wrong. He could inspect the contract ten times and still sign whatever Orochimaru wanted him to sign.
Fortunately, Ren had another layer of protection.
Tsunade.
Even if Ren could not detect Orochimaru's genjutsu, Tsunade almost certainly could. The next time he visited Konoha Hospital, he planned to show her the contract and explain exactly how he had ended up working at the Research Institute.
Ideally, he would leave his copy of the agreement with her.
It was less a contract than personal accident insurance. If Ren suddenly disappeared, grew scales, woke up inside a glass container, or returned home with several organs missing, Tsunade would know exactly whose laboratory to demolish first.
With that reassuring thought in mind, Ren watched Orochimaru sign both copies.
The Sannin pressed the Research Institute's official seal beneath his name before handing one copy to Ren. He rolled up the other, lifted it toward his face—and pushed the entire thing into his mouth.
Ren's eyelid twitched.
The scroll slid between Orochimaru's lips and disappeared down his throat without resistance. There was not even a visible bulge.
Ren stared despite himself.
You have pockets.
I can see them.
Why would anyone choose to store an official contract inside their stomach?
Then Ren remembered that Orochimaru was capable of pulling the Kusanagi Sword out of his mouth. Compared with storing a full-sized blade somewhere in his digestive system, swallowing a small scroll was almost reasonable.
Almost.
Orochimaru either failed to notice Ren's expression or simply chose to ignore it. He rose from his seat with a satisfied smile and gestured toward the reinforced door at the rear of the laboratory.
"A pleasant cooperation, Ren-kun. Since this is your first day at the Research Institute, your initial assignment will be simple."
His hand pressed the locking mechanism.
The heavy door opened with a metallic groan.
Ren immediately tensed, remembering the scraping sound he had heard from the other side. Instead of a mutilated test subject, however, he found a long underground corridor lined with observation windows.
A large snake was thrashing inside a reinforced transport enclosure beside the wall. Its claws—if those strange hooked growths could be called claws—scraped against the metal floor as two researchers wheeled the container away.
Orochimaru glanced at Ren's guarded posture, and amusement flickered through his eyes.
"I'm going to show you around."
Ren slowly relaxed.
For now, it seemed the contract had saved him from being thrown directly into Orochimaru's darkest experiments.
What tomorrow might bring was another matter.
The Research Institute was far larger than Ren had expected. Orochimaru led him through a maze of laboratories, storage rooms, operating areas, and narrow passages that extended deep beneath the surface.
Each section specialized in a different field.
The sterile culture rooms contained racks of blood and tissue samples, each stored in a carefully labeled glass vessel. Researchers wearing masks moved between them while recording changes in color, density, and chakra response.
The equipment rooms housed microscopes, pressure chambers, chakra-measuring instruments, and centrifuges large enough to process dozens of samples at once. Beyond them were refrigerated vaults where cells and preserved organs were stored at controlled temperatures.
Every new room made Ren's understanding of the shinobi world feel slightly less reliable.
He had always known that its technological development was inconsistent. Radios, cameras, medical equipment, and complex machinery existed alongside handwritten messages and travel by foot.
Seeing the contradiction gathered in one place was still astonishing.
Ren stopped beside a researcher who was examining a tissue sample through a sophisticated microscope.
A kerosene lamp sat beside the instrument.
Its weak yellow flame provided most of the light.
Ren stared at the microscope, then at the lamp.
You have developed giant centrifuges capable of processing chakra-infused blood, but fluorescent lighting is apparently where science draws the line?
He resisted the urge to ask.
Questioning the logic of this world would only result in a headache, and Orochimaru was watching him far too closely.
Despite his silence, Ren's familiarity with the equipment soon became impossible to hide. Orochimaru demonstrated the operation of each instrument only once, yet Ren remembered nearly every step.
He quickly understood how to prepare slides, balance sample containers, adjust magnification, sterilize tools, and record changes in tissue cultures. When Orochimaru allowed him to operate several basic machines, Ren showed almost none of the clumsiness expected from a complete beginner.
Orochimaru watched him finish calibrating a centrifuge.
"It appears Tsunade has given you an excellent foundation," he observed. "Most new assistants require at least a week to become comfortable with these instruments. Some need considerably longer."
"I still have much to learn," Ren replied modestly. "Lady Tsunade taught me the fundamentals, so the rest isn't especially difficult to understand."
It was a believable explanation.
The truth was that Ren's memories from his previous life gave him a tremendous advantage. The instruments were different from the ones he had known, especially those designed to measure chakra, but their underlying principles were not completely alien.
Orochimaru continued to study him.
Ren pretended not to notice.
As they moved deeper into the institute, several heavy metal doors appeared at the far end of a restricted corridor. Unlike the ordinary laboratories, these entrances lacked windows, labels, or visible handles.
Complex sealing formulas covered their surfaces.
When Ren passed them, he caught the faint scent of blood beneath the overwhelming smell of disinfectant. A moment later, something resembling a muffled whimper reached his ears.
His footsteps almost slowed.
Almost.
Ren kept his gaze fixed ahead and continued walking as though those doors did not exist.
He did not ask what lay beyond them. He did not glance toward them a second time, nor did he allow his chakra to spread in that direction.
The difference between curiosity and stupidity was knowing when not to open a door.
Those sealed rooms were likely where Orochimaru conducted the research he could never present to the Third Hokage. Whatever happened inside them had nothing to do with organizing samples or operating equipment.
At least, not yet.
Orochimaru glanced at Ren from the corner of his eye. Something like approval briefly appeared on his face, although he offered no explanation.
By the time the tour ended, Ren had memorized the institute's public sections, emergency exits, supply rooms, and basic safety procedures. More importantly, he knew which corridors to avoid.
They returned to the first laboratory.
Orochimaru reached toward his mouth.
Ren immediately understood what was about to happen and prepared himself.
A moment later, the Sannin pulled out another scroll covered in a thick layer of clear, milky slime. He held it toward Ren as casually as if it had come from an ordinary storage pouch.
Ren stared at it.
His new job was already testing him in ways the contract had failed to anticipate.
"According to our agreement, your salary will be calculated and paid at the end of each month," Orochimaru said. "Since today is only your first day, I do not technically owe you anything yet."
He extended the dripping scroll a little farther.
"Consider this an advance payment and a gesture of sincerity. It is a small technique I developed personally. I believe you will find it useful."
A familiar notification appeared before Ren's eyes.
[Giftable item detected.]
[Limited Skin—Transformation Technique: Snake-Limb Hardening]
Ren blinked.
Snake-Limb Hardening was compatible with the Transformation Technique.
That was genuinely unexpected.
Unfortunately, the scroll containing it looked as though it had been recovered from the bottom of a snake's stomach—which, now that Ren thought about it, might have been exactly what had happened.
He hesitated for two seconds before forcing himself to accept it.
"Thank you, Lord Orochimaru."
The surface was warm.
Ren immediately decided he would disinfect it several times before opening it.
Orochimaru smiled, clearly satisfied with his reaction.
"You're welcome, Ren-kun. I look forward to seeing what you do with it."
That evening, Ren sat inside his room with the scroll spread across his desk. Before bringing it home, he had wiped it clean, washed it with disinfectant, dried it in the sun, and wiped it again for emotional reassurance.
Only then did he present the scroll to the Transformation Technique.
The system reacted instantly.
[Transformation Technique: (Eyes filling with tears) Is this really for me? Ren prepared a new outfit especially for me! It appears to be made from snakeskin, but a gift is a gift. I love it!]
[Clone Technique: Ren, you heartless brat! You finally remembered that I deserve new clothes too. At this rate, we might actually catch up with that show-off someday!]
[Great Fireball Technique: ?]
[Great Fireball Technique: What did I do?]
The ninjutsu immediately began arguing among themselves.
Ren watched the stream of messages with an amused expression before turning his attention back to the new ability.
This gift confirmed an important possibility.
Orochimaru possessed several techniques that might qualify as limited skins. If Snake-Limb Hardening belonged to the Transformation Technique, then his Soft-Body Modification and Vanishing Facial Copy Technique might be compatible with it as well.
Orochimaru's unusual substitution technique—the one that allowed him to emerge from his own discarded body—might qualify as a skin for the Substitution Technique.
Those abilities were much more advanced, however. Obtaining them would not be as easy as accepting a first month's payment.
Ren was not disappointed.
Receiving Snake-Limb Hardening on his first day had already exceeded his expectations. As long as he continued working at the institute and remained useful to Orochimaru, other opportunities would eventually appear.
He activated the new ability.
Chakra flowed through his right shoulder before spreading down his arm. His skin tightened, and the muscles beneath it compressed until the entire limb felt heavier and denser.
A faint pattern resembling snake scales appeared across the back of his hand.
Ren struck a wooden training post.
The impact produced a sharp crack.
The post shook violently, and a shallow crater appeared where his fist had landed. Ren felt the force travel up his arm, but there was almost no pain.
He picked up a kunai with his left hand and carefully drew its edge across the hardened skin. The metal scraped against his forearm with a harsh sound, leaving only a thin white mark.
His eyes brightened.
The Transformation Technique had gained a genuine defensive combat form.
Snake-Limb Hardening worked by gathering and compressing chakra inside a chosen limb, reinforcing the muscles, bones, and skin. Its durability was roughly comparable to that of an ordinary ninja tool.
It could not withstand everything. A chakra-enhanced weapon or high-level ninjutsu would still break through it, and it was nowhere near strong enough to block the chakra blade once wielded by the White Fang.
Even so, the technique had enormous practical value.
Ren could use a hardened forearm to deflect kunai, survive a sword strike, or strengthen his punches without revealing a complicated ninjutsu. If activated at the right moment, it could overturn the outcome of close combat.
It was exactly the kind of technique Ren preferred—simple, fast, and deceptive.
After practicing several times, he deactivated the ability and examined his arm. Apart from mild chakra exhaustion, there were no obvious side effects.
His thoughts shifted to the Inscribed Blade, which had been sent away for modifications. He still did not know when the work would be completed.
There was also the invitation from Fugaku.
Building a connection with the Uchiha clan could prove valuable, especially with war approaching. If Ren handled the relationship carefully, he might gain access to Fire Release knowledge or even secure opportunities to spar against Sharingan users.
That possibility alone made the visit worthwhile.
When the weekend arrived, Ren purchased two boxes of milk and headed toward the Uchiha clan compound.
The district was quieter than the center of Konoha. Members of the clan moved through its streets with the natural confidence of people walking on land their families had occupied for generations.
Ren had barely reached Fugaku's home when the front door opened.
Fugaku stepped outside and paused in surprise.
"Ren?"
His stern expression quickly softened into a smile when he noticed the milk in Ren's hands.
"You actually came. There was no need to bring anything with you."
"I only wanted to thank you for helping me with the Police Force matter," Ren replied, offering him the boxes. "It isn't much, but I couldn't visit empty-handed."
Fugaku accepted the gift with visible satisfaction.
"You are far too formal for someone your age. Come inside and sit with us for a while."
Ren was about to respond when a woman emerged from the house behind Fugaku. Uchiha Mikoto wore a gentle smile, and a small child rested quietly in her arms.
The infant had dark hair and large black eyes.
Ren's gaze lingered on him.
That child could only be Itachi.
At this age, he was not yet a prodigy, ANBU captain, clan killer, or tragic hero carrying the hatred of an entire village. He was simply a baby who neither cried nor laughed, calmly observing the stranger standing outside his home.
Fugaku noticed Ren's attention and turned slightly toward his wife.
"This is my son, Itachi. He's cute, isn't he?"
"Very," Ren answered honestly.
Mikoto stepped closer, allowing Ren to see the child more clearly. Itachi stared at his white hair with silent curiosity before reaching one small hand toward him.
Ren offered a finger.
Itachi grasped it.
For reasons Ren could not explain, the simple touch made his chest feel unexpectedly heavy.
Fugaku, unaware of his thoughts, looked proudly at his son.
"It's a shame he was born a little too late. If he were two years older, he might already be preparing for the Academy." He chuckled. "Still, a few years will pass quickly. Perhaps he'll graduate at five like Kakashi."
Ren maintained his smile.
Graduating at five might be unlikely.
Being taken to a battlefield at that age, however, was entirely possible.
In the original course of history, Itachi's beliefs would become twisted by war, duty, manipulation, and impossible choices. Yet Fugaku could not be absolved of responsibility. Bringing a four-year-old child onto a battlefield and forcing him to witness mountains of corpses was hardly a sensible lesson in peace.
Ren looked at the baby holding his finger.
This child had not yet seen blood.
Perhaps that future could still be changed.
Fugaku's family appeared ready to leave, so Ren did not remain for long. After exchanging a few polite words with Mikoto and promising Fugaku that he would visit again for a spar, he excused himself.
He planned to spend the afternoon testing Snake-Limb Hardening at his usual training ground.
Ren had only walked a short distance from the Uchiha compound when a shadow dropped silently onto the road before him.
An ANBU operative wearing a tanuki mask knelt on one knee.
Ren stopped immediately.
"Genin Ren," the operative said, raising his masked face. "Jōnin Kushina Uzumaki has ordered me to bring you to her."
Ren's expression changed.
Kushina had never summoned him through ANBU before.
The masked shinobi rose, and his next words erased any thought of refusing.
"She said it concerns the Nine-Tails."