"No problem."
Ren smiled, already imagining a new potential conquest target appearing inside the Gala System.
If ordinary ninjutsu could be personified, then fūinjutsu should be no exception. The only question was what kind of personality a sealing technique would possess.
Calm and disciplined?
Cold and restrictive?
Or perhaps frighteningly possessive?
"I'll thank you in advance, Minato-sensei."
Minato nodded.
The two rested beneath a tree while waiting for the remaining members of the team to complete their assigned training.
A short while later, Kakashi, Rin, and Obito entered the training ground. Their clothes were damp with sweat, their breathing remained slightly uneven, and all three carried the unmistakable exhaustion produced by Minato's special training.
Obito spotted Ren sitting beneath the shade and immediately pointed at him.
"Ren! You're slacking off while the rest of us are suffering!"
Before Ren could respond, Kakashi gave an irritated snort.
"Be quiet, dead last. Ren was developing a new combat technique with Minato-sensei."
Obito's exhaustion vanished.
"A new technique?"
He rushed toward them, nearly tripping over a root.
"I want to develop one too!"
Kakashi glanced at him.
"You should master the Fire Release techniques you already know before trying to create new ones."
Obito's eyebrow twitched.
"What's your problem lately, Kakashi? You disagree with everything I say!"
"I disagree when you say something stupid."
"Stinky Kakashi!"
Obito rolled up his sleeves.
"I've learned two new Fire Release techniques recently. If you dare to spar with me, I'll show you something that will wipe that bored look off your face!"
Kakashi turned away with a dismissive hum.
"You'll probably set your own clothes on fire."
"What did you say?"
Rin sighed as the two began arguing again.
"Those two really can fight about anything."
"They were born to annoy each other," Ren said.
Obito immediately turned toward him.
"Whose side are you on?"
"Whichever side ends the argument faster."
Neither of them seemed satisfied with that answer.
Once their bickering finally quieted, Ren drew the short sword Kakashi had loaned him.
"I need to ask you something."
Kakashi's attention shifted toward the blade.
Ren briefly explained the proposal he had discussed with Minato. He described inscribing a binding formula onto the weapon, allowing even a shallow cut to disrupt an enemy's chakra flow or temporarily restrict their movement.
Kakashi listened without interrupting.
When Ren finished, his visible eye moved from the blade to Minato.
"Would engraving the seal weaken the metal?"
"It shouldn't, provided the formula is properly designed," Minato answered. "Kushina would also need to examine the blade before making any permanent changes."
Kakashi considered the matter for several seconds.
The sword was not an ordinary training weapon. It was connected to his father and carried greater meaning than Ren could fully understand.
Ren did not rush him.
Finally, Kakashi nodded.
"You have my permission, as long as the seal doesn't damage the blade or interfere with its ability to channel chakra."
"Thank you."
Ren grinned and placed a hand on Kakashi's shoulder.
"If I get the opportunity, I'll repay you by stealing the Executioner's Blade from Kirigakure."
Kakashi stared at him.
"The giant sword belonging to the Seven Ninja Swordsmen of the Mist?"
"That's the one."
"It's taller than both of us."
"You'll grow."
"That isn't the problem."
Ren returned the short sword to its sheath.
"Then I'll steal you something smaller."
Kakashi closed his eye, seemingly regretting his decision already.
Obito scratched his cheek.
"So, if someone gets cut by the sword, the seal activates and stops them from moving?"
"That's the idea," Ren answered.
"That sounds amazing!"
Obito spun toward Minato.
"Can I learn fūinjutsu too?"
Minato did not immediately respond.
"Sealing techniques don't naturally match your current combat style," he said after a moment. "Your strengths lie in Fire Release, stamina, and direct combat."
Obito's face fell.
"However, there's no harm in learning the fundamentals," Minato continued. "Even if you never use fūinjutsu yourself, understanding how seals work will help you recognize and counter them."
Obito raised both fists.
"Yes!"
Minato looked toward Kakashi and Rin.
"The same applies to both of you. When I begin teaching Ren, everyone can attend."
Rin smiled.
"I'd like that. Sealing knowledge may also be useful for medical ninjutsu."
"It is," Minato confirmed. "Some medical procedures use seals to preserve organs, stabilize chakra, or safely store medicine."
Kakashi gave a small nod.
"If it helps me recognize traps, I'll learn it."
With the matter settled, Minato raised two fingers.
A moment later, he disappeared in a yellow flash.
Rin blinked.
"Where did he go?"
Before Ren could answer, another flash appeared in the same spot.
Minato returned holding two thick books.
The entire trip had taken less than a minute.
Ren stared at him.
The Flying Thunder God was one of the most powerful space-time ninjutsu ever created, capable of crossing enormous distances in an instant and turning Minato into a terror on the battlefield.
Yet he had just used it to go home and retrieve books.
Flying Thunder God: Homecoming Edition.
The convenience was almost offensive.
Minato handed the books to Ren.
"Read these first."
The first volume was titled Fundamentals of Fūinjutsu. The second was Chakra Script Structure and Energy Guidance.
Both were thick enough to be used as blunt weapons.
"The first book explains basic inscriptions, chakra injection, storage formulas, and the difference between sealing and barrier techniques," Minato said. "The second focuses on how chakra travels through written formulas and how to prevent instability."
Ren opened the first book.
The initial page contained dozens of symbols connected by lines, circles, and directional markers.
It resembled a combination of calligraphy, mathematics, and electrical engineering.
Minato continued.
"Before attempting to create any seal, you must understand how to draw each script correctly and how chakra moves through it. A single incorrect stroke can change the formula's function."
Obito leaned over Ren's shoulder.
"What happens if you write it wrong?"
"The seal might fail."
"That doesn't sound too bad."
"Or it might activate in reverse, explode, drain the user's chakra, or seal the wrong target."
Obito immediately stepped back.
"I'll let Ren practise first."
Kakashi gave him a contemptuous glance.
"Coward."
"I'm being cautious!"
Minato smiled and pointed toward the books.
"Once you understand those two volumes, I'll begin teaching you practical fūinjutsu."
"Understood."
Ren accepted the books.
Even if he could not master the Flying Thunder God, entering the field of fūinjutsu was an enormous opportunity.
Sealing techniques were among the most versatile abilities in the shinobi world. They could suppress tailed beasts, create barriers, restrict movement, store weapons, preserve objects, disrupt chakra, and even interact with souls.
A powerful ninjutsu might win one type of battle.
A sufficiently advanced seal could solve almost any problem.
Several days passed.
Team Minato's routine remained relentless.
They trained in physical conditioning, chakra control, combat awareness, and teamwork. Ren also used every spare moment to study the fūinjutsu books, though progress was slow.
The material required a different kind of thinking from ordinary ninjutsu.
Ninjutsu relied on molding chakra, completing hand seals, and releasing an effect.
Fūinjutsu required the user to construct a stable system. Every line had a purpose. Every symbol controlled a different function, and all of them had to work together without conflict.
On the evening of the fourth day, Team Minato finished another round of special training.
The four genin collapsed in a forest clearing.
Obito lay flat on his back, staring blankly at the sky. Rin sat against a tree, massaging her exhausted legs, while Kakashi leaned nearby with his eye closed.
Ren remained seated only because lying down would probably cause him to fall asleep immediately.
They had been resting for approximately twenty minutes when a familiar distortion appeared in the clearing.
Minato emerged through the Flying Thunder God.
Despite having returned from another assignment, he looked remarkably composed. His gentle smile returned when he saw his students scattered across the ground.
"You've all worked hard."
Obito lifted one hand weakly.
"Minato-sensei, I can't feel my legs."
"That means you completed the training properly."
"That isn't comforting."
Minato looked over the group.
"You've all been diligent during the past month, and I'm pleased with your improvement. Let's stop here for today."
No one moved.
They lacked the strength to celebrate.
Then Minato added, "Dinner is on me tonight."
Obito sat up instantly.
"Really?"
Energy returned to his body as though someone had fed him a soldier pill.
"Are we going to Yakiniku Q? I haven't eaten there in ages! But it's expensive, so Ichiraku Ramen would also be fine. I can eat at least six bowls."
"Neither," Minato replied.
Obito froze.
Minato smiled.
"You're all coming to my home. I'll cook."
Ren looked up.
Rin's eyes widened.
"You know how to cook, Minato-sensei?"
"A little."
Minato raised his hand and held his thumb and forefinger close together.
Ren stared at the tiny gap between them.
Considering Minato's habit of describing advanced fūinjutsu knowledge as "a little," that answer could mean anything.
"Go home, bathe, and change your clothes," Minato instructed. "Come to my apartment in about an hour. I still need to buy the ingredients."
Obito immediately jumped to his feet.
"I'll be there!"
Rin smiled.
"Thank you for inviting us."
Kakashi appeared indifferent, but he did not refuse.
An hour later, Ren and Rin met Kakashi near the old Hatake residence.
Kakashi had changed into clean clothes and was waiting beside the narrow path leading toward the Uchiha district. The three of them continued together until they reached Obito's home.
Ren knocked on the door.
It opened almost immediately.
Obito's hair was still wet, and several drops of water rolled down his face. He had clearly rushed through washing and changing because he was too excited to wait.
"What took you so long?" he demanded.
"We arrived on time," Kakashi said.
"You arrived slowly."
"That sentence doesn't make sense."
Before another argument could begin, Rin stepped between them.
"Minato-sensei is waiting. Let's go."
They left the Uchiha compound and headed toward the civilian district.
Minato's residence was not the apartment where Naruto Uzumaki would live many years later. It was a modest detached apartment located on a quiet street.
A small courtyard surrounded the building. The plants were neatly trimmed, the path had been swept clean, and not a single object seemed out of place.
Ren knocked on the door.
"Minato-sensei, we're here."
"Come in and make yourselves comfortable," Minato called from the kitchen.
The sound of vegetables sizzling in a pan accompanied his voice.
The four genin removed their shoes and entered.
The apartment contained one bedroom, a living room, a kitchen, and a small bathroom. It was not large, but it was bright and immaculately clean.
Books and scrolls covered most of the low table in the living room.
Several maps had been pinned to one wall, while another displayed rows of specialized ninja tools. Most were Minato's distinct three-pronged Flying Thunder God kunai.
Obito approached the display with sparkling eyes.
"Minato-sensei has so many weapons!"
"Don't touch them," Kakashi warned.
"I wasn't going to."
"You were already reaching."
"I was only looking closely!"
Ren and Rin wandered around the living room, curious to see how their teacher lived.
Kakashi sat properly near the table, his back straight and his hands resting on his knees. He looked less like a guest and more like a guard assigned to protect the furniture from Obito.
Several minutes later, someone knocked on the door.
Knock. Knock. Knock.
All four genin looked up.
Every member of Team Minato was already present.
Ren glanced toward the kitchen.
Could Minato have invited someone else?
"I'll answer it!"
Obito jumped up before anyone could stop him.
He hurried to the entrance and pulled open the door.
A tall young woman stood outside.
Her long, brilliant red hair fell down her back like a river of flame. Violet eyes shone with lively warmth, and a bright smile spread across her face the instant she saw Obito.
"Oh! You must be one of Minato's students!"
Before Obito could respond, she reached toward his head.
"Come here and let your big sister take a proper look at you!"
"Whoa!"
Obito's training saved him.
He ducked beneath her hand with an awkward movement and retreated into the house, his face turning bright red.
"W-Who are you?"
The red-haired woman laughed and stepped inside as if she owned the place.
Her gaze swept across the living room before settling on Rin.
"Oh, what an adorable girl!"
She crossed the room in three quick steps and gently pinched Rin's cheeks.
Rin had no time to react.
"Mmph!"
Her cheeks puffed between the woman's fingers, and her face turned crimson from embarrassment.
The red-haired woman released her and immediately looked toward Ren.
Ren felt danger.
He shifted his weight, preparing to dodge.
Too late.
Her hand moved with frightening speed.
Two fingers caught his cheek and gave it a playful tug.
"So you're Ren! Minato has told me quite a lot about you."
Ren stared into her delighted violet eyes.
This was the woman Minato had described as gentle.
Behind them, Kakashi quietly moved farther away.
The red-haired woman noticed.
Her smile widened.
Kakashi stiffened.
Kushina Uzumaki—the Red-Hot Habanero—had arrived, and only one member of Team Minato remained unpinched.