The Final Experiment

"... Radiation source... Safety valve... What do I do? It's so annoying..."

"The Tailed Beast's Chakra is too corrosive... Separate it, safely separate the Tailed Beast's Chakra... No, no, there's something wrong with this path."

The underground cell smelled strange; damp straw emitted a musty odor, the scent of dried blood contrasted sharply with that of fresh blood, and the burning oil lamps emitted a pungent odor. A multitude of indescribable smells mingled together, making the air exceptionally murky.

The dungeon's history isn't long, but it's not short either, about twenty years.

What's interesting is that this dungeon was built by Konoha Ninja. During World War I, Konoha Ninja stationed in the Land of Grass built many similar dungeons in their various camps to imprison prisoners.

Most of them have been abandoned and destroyed by now, but the dungeon here has been preserved because it was used by the Grass Ninja for a period of time and received some repairs and maintenance.

However, the dungeon environment was still very harsh.

The oil lamps were extremely dim, and two of them were extinguished by a slightly stronger gust of wind.

"... Damn it, out of gas again?"

Katsuki muttered softly, paused her work, picked up the oil can from the corner of the wall, quickly walked to the extinguished oil lamp, and skillfully added oil and lit it.

The dim vision suddenly brightened, and the previous light was restored.

In researching the Jinchuriki, Katsuki took on all the work himself, even doing chores like adding oil to the lamps.

Loneliness is a spiritual celebration, capable of maximizing inspiration. Enduring and enjoying solitude often sparks new ideas.

He had been underground for three days. During that time, apart from people bringing him food and water at regular intervals, the only two people in the huge dungeon were Katsuki and Han, but their relationship was that of researcher and researched, and the atmosphere between them was anything but friendly.

... As expected, the most troublesome issue is the extremely close connection between the Tailed Beast and their Jinchuriki. The Tailed Beast is practically equivalent to the Jinchuriki's other 'heart'; removing the Tailed Beast is like ripping out the Jinchuriki's heart...

Katsuki crossed her arms over her chest, sizing up the listless Han, lost in thought.

Even though Katsuki's medical skills were not weak, the repeated experiments involving opening up the abdomen still caused Han enormous mental stress and severely depleted his physical strength. The food provided each day was barely enough to keep Han from fainting from hunger, and as a result, Han was so hungry that his limbs were weak.

There was resistance during that period, though.

For the sake of convenience in the experiment, the chains binding Han's limbs were replaced with a very thin type, which had almost no actual restraining force and was completely negligible to Han.

However, Han's nine sneak attacks failed once. With his Chakra sealed, he was just an ordinary human being weak from hunger. Even though he could rely on the good foundation left by his strong physique, he could easily be slapped over.

By now, Han had fallen into utter despair; he no longer wished to leave alive, but only to die quickly.

Watching himself being disemboweled time and time again, his internal organs being weighed out, this grotesque experience tormented his fragile nerves constantly. He was terrified that if this continued, he would go insane before death even arrived!

"Kill me... kill me..."

Like a curse from hell, a voice filled with despondency, weakness, and hatred echoed through the cell.

"Aren't you going to resist anymore?" Katsuki asked, tilting her head.

"... Kill me... Kill me..."

It's the same sentence over and over again.

Katsuki frowned. Was he already on the verge of a breakdown? How boring...

"Well, it's about time." Katsuki pulled a crumpled letter from her pocket. It had been delivered with lunch that day. The message was short, saying that the war between the Sand Village and the Stone Ninja had come to an end, and they no longer had any reason to stay in the Land of Grass.

After all, having several thousand people idly stranded in the Land of Grass is a considerable burden on the village's finances and a huge waste of human resources.

"I'm going back to the village tomorrow at noon, so today is the perfect opportunity to put an end to our feud... Hey, stop pretending. If you want revenge, hurry up and do it. If you don't make a move soon, I will..."

"Collapse! Collapse! Collapse..."

The sharp sound of metal shattering rang out almost simultaneously.

The man, who had been listless like a dead dog, suddenly sprang to life, easily breaking free of his chains, as agile as a tiger descending a mountain.

Looking at Katsuki's amused expression, Han's eyes flashed with a fierce light. He took a step forward, covering a distance of three or four meters, and instantly closed in on Katsuki. His fist, as big as a bowl, turned dark brown and swirled with a fierce wind as it slashed towards her.

"Bang--!!"

Her five fingers gripped Han's fist tightly like iron clamps. Katsuki's left hand turned iron gray, and the muscles in her left arm bulged exaggeratedly, severely disproportionate to her body.

Physical enhancement.

As the earliest ability developed through research on the Hito Hito no Mi, it has long since reached a state of perfection.

"I'm not afraid to tell you, don't let my appearance fool you, when it comes to strength... I'm confident I can hold my own against anyone." Katsuki's smile remained, her shoulders twitched, and she exerted her strength once more.

"Ahhh!!"

Han's eyes widened, his eyes bulged, veins throbbed on his forehead, and a shrill scream escaped his throat.

The fist that Katsuki was gripping made a series of popping sounds like popping beans, and the bones in her hand were crushed inch by inch.

He swung his left arm, taking advantage of his large size, and his fist mercilessly pounded on Katsuki's head, making a loud clang.

"Is this all you can do? Are you just tickling me...?" Katsuki pouted in disappointment. "Looks like I overestimated you... Steam Ninja, this is all you're capable of. No wonder the Akatsuki Organization captured you so easily."

"You... you bastard, you cunning brat, die, die..."

Han cursed as he pounded his fists, but he couldn't harm Katsuki in the slightest. Even when Guan Yue poked his head out and let him do as he pleased, he didn't suffer any damage.

"Go back to your bed."

With a powerful vibration from his left arm, a tremendous force erupted from his palm, shattering all the bones in Han's right arm. His burly body flew backward like a broken sack, crashing heavily into a pile of moldy straw in front of him.

"... Heh heh, die, die, monster of Konoha, monster..."

Lying in the haystack, smelling the musty odor, Han nervously muttered incessantly, cursing Katsuki.

"Next... let's begin the final experiment! To verify whether my theory is correct..." (To be continued)