The Solution

Early the next morning, at the back mountain of the Senju Clan Grounds.

Hyuga Yuto sat on a smooth bluestone slab, eating the rice balls and jerky Tsunade had brought him, occasionally taking a sip of piping-hot fish soup.

He was only thirteen this year, at the age when boys could eat their fathers out of house and home. As a ninja, his appetite was enormous. Seeing the lunchbox completely empty, Shizune stared at Hyuga Yuto as though she had spotted some rare creature.

"Y-you... you're not going to turn into a balloon and pop, are you?"

"How could that happen?" The branch family boy rubbed his stomach.

"I'm not stupid. Once I'm full, I'll obviously stop eating." He paused, then asked curiously, "Teacher is an expert in ninja taijutsu. Her appetite should be even bigger than mine."

Tsunade, who was fiddling with her hair nearby, shot him a glare.

"Commenting on a lady's appetite is very rude, you know."

After the group chatted for a while, Hyuga Yuto finished every last bite and let out a long breath.

"I'm done... Hmm, seventy percent full. The best condition for training."

Shizune picked up the lunchbox. Since she had to go to school, she did not linger and skipped down the mountain.

Tsunade watched her young female disciple leave and suddenly sighed.

"You're only a year older than Shizune, yet you're so much more mature..."

Hyuga Yuto stood without replying. He moved away, loosened up his wrists and neck, and removed his bandages while he was at it.

The blonde woman chuckled.

"Careful, aren't you? Don't worry, I won't sneak-attack you..." She crooked a finger at her disciple. "Come. Use that technique and hit me with it."

"Teacher..." Hyuga Yuto's expression turned solemn. "If you take it head-on, you could really die."

"You won't burst from eating rice balls, so do you think I'd be stupid enough to take it without doing anything?" The blonde woman stepped back. "Come, my cute disciple. At your current level, you're still a hundred years too early if you want to kill your teacher."

That made sense, Hyuga Yuto thought. With the Strength of a Hundred Seal, she could use Ninja Art: Creation Rebirth. Its recovery ability was unparalleled in the ninja world. Her vitality was simply too great for him to worry about anything.

Scorching heat rose from the back mountain. The leaves instantly dried out and yellowed as high temperatures descended, and fine beads of sweat immediately formed on Tsunade's neck and cheeks.

This was merely the prelude, yet it had nearly set the entire forest ablaze.

Damn, this technique is stronger than I imagined... The blonde woman did not dare underestimate it. She bit open her fingertip and slammed both hands onto the ground.

"First Rashomon!"

Boom!

A massive gate appeared amid the forest, thick and rugged like a small mountain standing upright. Ferocious demon faces were carved into its surface, inspiring fear at first sight.

"Lion Fang..." Hyuga Yuto murmured as he charged straight ahead.

"Severance!"

He crashed into the center of the summoned Rashomon, and the enormous shockwave snapped every surrounding tree.

With a thunderous boom, the Rashomon was punched clean through. The edges of the hole had actually melted into liquid metal.

Hyuga Yuto's body swayed, but in the blink of an eye, he was before Tsunade. His right palm struck the blonde woman's abdomen.

Carrying the lingering force of Lion Fang Severance, he drove Tsunade through more than ten trees before finally coming to a stop.

I was too careless. I shouldn't have used my body to experience this technique, Tsunade groaned inwardly, though she forced herself to say, "That's enough... Yuto."

The chakra he had released dissipated. Hearing his teacher's words, Hyuga Yuto hurriedly withdrew his hand.

The clothing over Tsunade's abdomen had been shattered, exposing pale skin. Hyuga Yuto's palm print was clearly visible upon it.

"That's impressive, Yuto." Tsunade looked at the pierced Rashomon, then carefully examined her injuries. "The high heat and fangs are flashy, but this technique's real destructive power comes from the high-speed flow of chakra. Unlike the Rasengan, which rotates around its core, your technique is much more complicated. It has many small vortices and tiny hurricanes spinning in opposite directions... Hiss."

Touching a bruise, the blonde woman frowned and sucked in a cold breath.

"My internal organs were damaged too... It has the blunt impact of Earth Release, while its air-cleaving charge resembles Lightning Release... Honestly, it still has this much power after piercing the Rashomon. An ordinary jonin would certainly die from this blow, and most defensive ninjutsu would be helpless against it."

"It's an excellent technique, perfectly suited to you, but it isn't without flaws."

"Your arm is already difficult to raise, isn't it? This technique puts too much burden on its user. It fully deserves to be ranked S-class, but it would also be classified as a forbidden technique."

The blonde woman rubbed her lower abdomen. Her pale skin was marked by burns and wounds carved by the wind, while beneath it, her internal organs were bruised and bleeding.

As she felt the power of Lion Fang Severance, she was also considering how to solve this side effect.

Tsunade was not a masochist. She had allowed Hyuga Yuto to injure her so she could better understand the technique.

The reason Lion Fang Severance inflicted such severe damage on its user was simple: while destroying the enemy's body, it attacked the user in exactly the same manner. The only difference was the degree of force; the principle of destruction was identical.

Only by suffering the same injury as the user could she develop a solution specifically tailored to this burden.

Still, the blonde woman was shaken. At the instant Hyuga Yuto's palm touched her abdomen, she had nearly counterattacked on instinct. Tsunade understood that this was a bodily reflex forged through years of battle, and it meant something terrifying—just now, Hyuga Yuto had completely had the chance to bite straight through her waist.

Yuto... held back at the last moment. Tsunade glanced at Hyuga Yuto and decided that this disciple of hers was fairly dependable. At least he knew where to draw the line.

While healing her abdominal injuries, she thought about how to eliminate this technique's frightening side effect.

The best method would naturally be to add a "membrane" between the body and the released chakra, separating them and blocking the violent chakra from harming the user. But that would greatly shorten Lion Fang Severance's duration, perhaps even cause it to collapse on contact. After all, that protective membrane would also isolate Yuto's chakra.

"Unidirectional fluid transport..." The word suddenly came to Tsunade's mind. Something that could transmit chakra while shielding against its destructive force...

As far as she knew, no physical material in the world possessed such a property.

If she had to name something, Katsuyu could actually accomplish the task—before using the ninjutsu, she could wrap Katsuyu around Yuto's arm. Katsuyu was immune to physical attacks and, as a summoned beast, could transmit chakra. She could isolate the damage without obstructing the chakra's flow. But no matter how she looked at it, asking Katsuyu to do such a thing would be far too disrespectful... Besides, the preparation time would be too long. It could not be used in the ever-changing, complex circumstances of ninja battles.

The blonde woman rubbed her forehead in frustration, then suddenly froze.

Though she could not feel it, that motion made her think of the Strength of a Hundred Seal on her forehead.

Understanding dawned on her.

There was no need for shielding, resistance, or separation. There was another, gentler method that could eliminate this damage.

—Sealing!