"The Nine-Tails?"
Ren's expression changed as he stared at the kneeling ANBU operative. The quiet street outside the Uchiha compound suddenly felt far less peaceful.
The operative wearing the tanuki mask shook his head.
"That concerns Lady Kushina's security arrangements. As the Nine-Tails' jinchūriki, any unscheduled meeting outside her residence requires an ANBU escort. She did not disclose the specific reason she wishes to see you."
Ren relaxed slightly.
"So she isn't summoning me because something happened to the Nine-Tails?"
"No."
That was reassuring.
Ren considered the timing before remembering the chakra-conductive short sword he had entrusted to Kushina.
"Is this about my blade?"
"I was not informed."
"Did she ask only for me?"
The ANBU paused before answering.
"Lady Kushina said that if Rin Nohara, Kakashi Hatake, or your other teammates were nearby, they could accompany you. Their attendance is not required."
Ren immediately made his decision.
"In that case, I'll bring Rin."
Minato was currently away from Konoha. Meeting his girlfriend alone while he was absent—even for something completely innocent—could create unnecessary misunderstandings.
Rin's presence would prevent that.
There was no need to call Kakashi or Obito. Ren did not know whether Kushina had ever taught them sealing techniques in the original course of events, but he preferred to limit Obito's exposure to her knowledge.
The future Obito had succeeded in breaking the seal controlling the Nine-Tails. Ren still did not know exactly how he had learned enough about Kushina's seal to exploit its weakness during childbirth.
Perhaps Madara had taught him everything.
Perhaps some crucial information had come from Kushina herself without her realizing its future significance.
Until Ren understood more, caution was the safer choice.
Twenty minutes later, Ren and Rin arrived at a secluded training ground on the western side of Konoha.
Tall trees surrounded the clearing, and several barrier markers had been discreetly placed among the roots. Although the area appeared deserted, Ren sensed at least three people hidden within the nearby foliage.
The ANBU guards concealed their chakra well, but not perfectly.
As the Nine-Tails' jinchūriki, Kushina was never truly alone.
She was already waiting for them atop a wooden training post. Her fiery red hair had been tied into a high ponytail that blazed beneath the afternoon sun, and a familiar short sword spun casually between her fingers.
When she spotted them, her face immediately brightened.
"You're finally here!" Kushina jumped down from the post and landed lightly in front of them. "And you brought little Rin too!"
Before Rin could properly greet her, Kushina pulled her into a tight hug and rubbed her cheek against hers.
"Senior Kushina!" Rin protested, her face rapidly turning red. "I can't breathe!"
"You've become even cuter since the last time I saw you."
Kushina reluctantly released her before turning toward Ren. Without warning, she tossed the short sword across the clearing.
Ren caught it by the hilt.
The weapon was his Inscribed Blade, but it felt subtly different. Its balance had shifted closer to the guard, and the hilt was warmer and smoother beneath his fingers.
At first glance, the blade appeared unchanged.
Then Kushina gestured for him to channel chakra into it.
Ren followed her instruction.
The instant his chakra entered the hilt, countless black-and-red markings spread across the blade. They resembled fractures appearing across the surface of white porcelain, yet the pattern was far too precise to be random.
Ren raised the weapon closer to his face.
Each line was composed of tiny triangular symbols nested inside one another. They connected to form several interlocking rings, all circulating chakra in different directions without colliding.
The structure was intricate, dangerous, and strangely beautiful.
The Inscribed Blade had been transformed into a genuine sealing weapon.
Kushina planted her hands on her hips and raised her chin proudly.
"This is the dual-layer form of the Sealing Barrier Method. Since the blade was forged from chakra-conductive metal, modifying it was easier than I expected."
"Easier?" Ren examined the thousands of tiny symbols. "How long did this take you?"
"Only a few days."
Rin stared at her in disbelief.
Ren was equally speechless. Anyone else might have needed months to create such a complicated formula, but Kushina described it as though she had spent an afternoon repairing a kitchen knife.
She pointed at the hilt.
"You don't need to understand fūinjutsu to use the basic function. Inject chakra into the hilt, and the formula will activate automatically."
Kushina then indicated the dark-red patterns across the blade.
"If you wound an enemy while the formula is active, the seal will interfere with their chakra network. Their chakra circulation will become sluggish for a short time, making it much harder to mold chakra properly."
Ren immediately understood the tactical value.
"So their ninjutsu will become slower."
"Not just ninjutsu," Kushina replied with a fierce grin. "Genjutsu, chakra-enhanced taijutsu, medical ninjutsu—anything that requires precise chakra control will be disrupted."
Even slowing an enemy by half a second could decide a battle between shinobi.
A delayed hand seal could prevent a ninjutsu from activating. A momentary disturbance in chakra control could weaken a Body Flicker Technique, ruin the timing of a genjutsu, or create an opening during close combat.
Combined with Snake-Limb Hardening, the improved blade would make Ren far more dangerous at close range.
Kushina lifted one finger in warning.
"Don't become overconfident. Right now, you can only activate the formula by feeding chakra into it. That method is simple, but it wastes much of the seal's power."
"How much of its strength can I use?"
"Enough to disturb someone's chakra and slow their reactions." Kushina's expression became more serious. "However, if you want to bind an enemy or completely suppress their chakra, you'll need to understand the formula and control its individual layers yourself."
Ren looked down at the markings again.
In other words, Kushina had turned the sword into a beginner-friendly sealing tool. Anyone with chakra could use its simplest function, but unlocking its true power required genuine mastery of fūinjutsu.
"I understand," Ren said. "Then please teach me how to control it."
Kushina's grin returned.
"Good answer! Class is starting again, so both of you had better pay attention!"
Rin straightened immediately.
Kushina drew a large rectangular diagram in the dirt and began explaining the Sealing Barrier Method. When performed without a prepared tool, it required nine hand seals to guide the user's chakra while the formula was constructed.
The triangular runes formed the foundation. Each one received, redirected, or restricted chakra in a slightly different way.
The surrounding rings controlled circulation.
Their positions had to be exact.
If even one symbol was misaligned, the entire formula could weaken, collapse, or redirect its effect toward the caster. A mistake small enough to escape the naked eye could transform a binding seal into useless decoration.
Rin's eyes gradually lost focus as the diagram became more complicated.
She still forced herself to listen, mentally repeating every term Kushina used. Her talent for medical ninjutsu had made her patient and detail-oriented, but even she struggled to follow the constantly shifting relationships between the symbols.
Ren listened just as intently.
According to Kushina, the Sealing Barrier Method was considered one of the simpler branches of fūinjutsu. More advanced seals required the user to memorize dozens of rune structures and understand how those structures changed when layered together.
The Evil Sealing Method was far more complicated.
The Cursed Tongue Eradication Seal required extreme precision because it directly restricted speech and movement.
The Four Symbols Seal operated on an entirely different level. Its formula contained multiple interacting arrays, each capable of suppressing and circulating enormous quantities of chakra.
Compared with those techniques, the pattern engraved on Ren's sword was merely an introduction.
That introduction was already enough to overwhelm most shinobi.
Kushina crouched beside the diagram and began explaining how the inner and outer rings interacted. Ren followed the movement of her finger, committing each shift in chakra flow to memory.
Then a familiar notification appeared before his eyes.
[High-quality potential conquest target detected.]
[Target: Sealing Barrier Method]
[A limited-time Encounter Mission has been activated.]
Ren's concentration immediately sharpened.
It finally appeared.
The scene before him faded.
For an instant, Ren found himself standing inside a freezing iron cage. Darkness surrounded him, and the floor beneath his feet was covered in faintly glowing sealing formulas.
A red-haired girl sat in the corner with her knees drawn against her chest.
Her long hair concealed most of her face, while her black dress appeared to have been woven from countless interlocking runes. Heavy chains wrapped around her arms and ankles, leaving angry red marks against her pale skin.
A suffocating gloom surrounded her.
She did not look imprisoned by someone else.
She looked as though she had forged the chains herself.
Three choices appeared.
[A: Hello, I'm Ren. I'm sorry to disturb you, but do you need any help?]
[B: Those chains are beautiful. Would you mind wrapping me in them too?]
[C: Hey, look at me. I said, raise your head and show me your face.]
Ren stared at the options.
Option B seemed like an efficient way to get himself restrained, sealed, and possibly buried alive. Option C was even worse. Treating a hostile sealing technique like a disobedient child sounded like an excellent way to discover whether it could seal his mouth permanently.
That left only one reasonable choice.
Ren selected A.
The girl's body trembled.
Like a wounded animal startled by an approaching stranger, she slowly lifted her head from between her knees. Her hair parted enough to reveal a pair of hollow black eyes.
There was no light inside them.
Only the stillness of stagnant water.
[Sealing Barrier Method: Help me? Heh… Another self-righteous fool.]
The chains around her arms tightened with a metallic rattle.
[Sealing Barrier Method: I put these chains on myself. They keep that noisy, disgusting world away from me. Stand over there and stop bothering me. Otherwise…]
A faint, unsettling smile appeared on her face.
[Sealing Barrier Method: Heh.]
Ren felt a chill crawl up his spine.
Gloomy, withdrawn, hostile, and displaying obvious self-destructive tendencies.
There was no mistaking the type.
She's a full-blown landmine girl.
Trying to conquer a technique with this personality felt dangerous in an entirely different way. If he said the wrong thing, would she lower her favorability—or activate on her own and seal him?
The Water Formation Wall had been gloomy, but this girl made it look emotionally stable.
Ren decided not to rush. He would test her reactions carefully, increase her favorability one step at a time, and avoid doing anything that might cause the chains to tighten around his own neck.
"Ren?"
Kushina's voice cut through the illusion.
The iron cage disappeared.
Ren blinked and found Kushina leaning toward him, her violet eyes narrowed suspiciously. Rin was also watching him with concern.
"Why are you staring into space?" Kushina asked. "Did you understand anything I just explained?"
Ren immediately pressed his palms together in apology.
"Sorry, Senior Kushina. I became distracted while thinking about the structure of the inner ring. Could you explain that part again?"
Kushina studied him for another second before huffing.
"Fine, but pay attention this time. Fūinjutsu is dangerous. If you lose focus while drawing a real formula, you might seal your own hand."
Considering the personality he had just encountered, Ren suspected that possibility was more realistic than Kushina knew.
The lesson continued until sunset.
That evening, Kushina treated Ren and Rin to dinner at Ichiraku Ramen. Two ANBU operatives remained stationed on nearby rooftops, while a third disguised himself as an ordinary customer several seats away.
Their presence was unavoidable.
Kushina was Konoha's jinchūriki, and Minato—the person most capable of responding if the Nine-Tails' seal became unstable—was currently outside the village. The village leadership would never allow her to move around without protection.
While they ate, Ren asked about Minato's mission.
Kushina knew little more than he did. Minato had accepted a high-ranking assignment outside the Land of Fire, and the mission's details were confidential.
Ren was not overly worried.
According to the original timeline, Minato still had several years ahead of him. There would be plenty of opportunities to learn from him after he returned, including the chance to study the Flying Raijin Technique.
For now, Ren focused on his ramen.
Rin sat beside him, carefully separating a slice of narutomaki from her noodles. Across the counter, Kushina alternated between the two of them with an increasingly curious expression.
Ren noticed her staring but pretended not to.
That proved to be a mistake.
As their meal neared its end, Kushina placed her chopsticks across her empty bowl and leaned forward. Her eyes gleamed with the unmistakable excitement of someone about to interfere in another person's private life.
"Ren, Rin—I suddenly want to ask you two something."
Rin looked up innocently.
"What is it, Senior Kushina?"
Kushina's grin widened.
"Are the two of you dating?"
Rin inhaled a mouthful of broth.
She immediately began coughing, her face turning bright red. Ren froze with his chopsticks halfway to his mouth, while even the disguised ANBU operative at the end of the counter tilted his mask toward them.
Kushina rested her chin on both hands, looking delighted by the chaos she had created.
The question was simple, but Ren already sensed that one wrong answer could turn Ichiraku Ramen into a battlefield.