Tsunade's Laboratory

Early the next morning, in order to avoid drawing attention, Uchiha Yuu arrived at Konoha Hospital while there were still few people around.

Thanks to Tsunade's vigorous promotion, Konoha Hospital had not only ordinary doctors, but also a Medical Corps still in training.

However, it was not wartime, and few people were injured while carrying out missions. To obtain more volunteers, the Hokage had specifically arranged for some ninjas to undergo regular physical examinations at set intervals.

"Aaaah! Help!"

"You Medical Corps people have gone too far! We're cooperating with you, not letting you use our bodies for experiments!"

"It hurts, it hurts! What's with that syringe? Why are you stabbing it into my kidney?!"

The moment he reached the Medical Corps area of the hospital, he saw two ninjas rushing out in blind panic. Their faces were filled with terror, as though they had seen the most horrifying thing in the world.

One of them even had a needle stuck near his kidney as he desperately fled outside. But at that moment, a capable-looking woman suddenly appeared at the entrance.

Dressed in a white lab coat, she grabbed the two fleeing men and dragged them back, speaking in the gentlest tone she could manage:

"The Will of Fire teaches you to make sacrifices. To advance Medical Ninjutsu and help more injured people keep their lives, this little sacrifice is necessary!"

"You should be able to make sacrifices for the village, right?"

Like chicks in her grasp, Tsunade firmly seized the two men, lifted them up, and pressed them against the wall as she continued:

"If you aren't willing, that's fine too."

Those words gave the two men hope. They raised their heads to look at Tsunade and tentatively asked:

"Really? Then we'll be leaving..."

"You misunderstood what I meant."

Tsunade gave a light squeeze, then struck the wall behind them with a heavy blow, spreading cracks across a wide area.

"I meant that since you aren't volunteers, I'll help make it a reality. Don't worry, with me personally handling it, it won't affect your ninja careers."

Struggling desperately, the two were dragged back into the operating room.

And Uchiha Yuu, who had just pushed open the door, happened to witness the entire scene.

He stood there in utter disarray. He had thought entering Tsunade's laboratory would already be miserable enough, but now he realized he had underestimated just how ruthless Tsunade could be.

If she stabbed a syringe into his kidney...

He could not stop himself from shuddering.

Run! He had to run! He absolutely could not fall into Tsunade's hands.

Unfortunately, Tsunade spotted Yuu the moment he entered the experimental area. A figure appeared behind him, blocking his wheelchair, hands resting on his shoulders as she leaned down toward him.

Looking up from below, Yuu's view was completely blocked by a pair of towering peaks. Someone with such a magnificent figure could only be Tsunade, even without seeing her face.

"Good morning, Lady Tsunade!"

"Good morning. Sorry you had to see that."

Without asking for his consent, Tsunade pushed his wheelchair forward. Perhaps feeling that what had just happened was too violent and did not fit her image as a doctor, she forcibly offered an explanation:

"But they volunteered. To promote the development of Medical Ninjutsu in the village, necessary sacrifices must be made. Besides, Medical Ninjutsu can stimulate cells and make them stronger."

"Don't overthink it."

She lightly patted his shoulder. If he had not just witnessed that scene, he might have thought Tsunade was merely conducting a normal experiment.

Now, even though Uchiha Yuu knew he had boarded a pirate ship, there was no way for him to escape Tsunade's experimental area.

"Lady Tsunade! I hope you'll be a little gentler with the upcoming experiment!"

His only answer was the scenery rapidly flying backward. Afraid that something else might happen, Tsunade immediately brought him into the experimental area.

Once inside, it was nothing like he had imagined. He had expected a bloodstained operating table, only to find a pristine white corridor instead. Rooms lined each side of the passage, and several ninjas patrolled at fixed positions.

The security measures here could be called the best in the village. Even an Elite Jonin would have no way of forcibly breaking through.

Just as Tsunade had said, even when conducting human experiments, she would ensure the ninjas' lives and their futures.

After passing through the corridor, they reached a hidden door. Beyond it lay Tsunade's laboratory, the most crucial place in the entire area. Two Elite Jonin stood guard outside the door alone.

"Lady Tsunade!"

"Lady Tsunade!"

Only after a series of inspections could they enter. Konoha's most precious Medical Ninjutsu was preserved here.

Seeing Uchiha Yuu lying on the operating table, Tsunade guiltily shut the door. Now, there was absolutely no way he could escape. With a hint of apology, she said:

"Ahem, let me explain this in advance."

"This ninjutsu is still in the developmental stage. Although it has already shown obvious results, it comes with pain. You'll have to endure it."

Before Yuu had a chance to say anything else, a ball of green chakra appeared in Tsunade's hand.

"Advanced Medical Ninjutsu! Mystical Palm Technique!"

Her control over chakra was practically monstrous. Even though she had trained so many medical ninjas, only a handful were capable of mastering the Mystical Palm Technique.

Layer after layer of bandages was unwound. Compared with several days ago, the skin had improved somewhat. Now, only below the knees remained a tangle of flesh and bandages.

Uchiha Yuu could feel a warm current of chakra flowing throughout his entire body. This chakra stimulated his cells, using stimulation to promote cellular recovery.

However, because he had not absorbed enough sunlight, the newly generated cells were immediately destroyed by the tyrannical radioactive elements within his body.

Throughout the process, he also had to restrain them with extreme care. Radioactive elements were highly harmful to ninjas; even an Elite Jonin exposed to them would suffer genetic mutations.

To allow Tsunade to perform the operation smoothly, he had worried himself sick.

Still, one thing was certain: the Mystical Palm Technique did help his body to some extent, because it contained Yang-natured chakra. Unfortunately, it still differed somewhat from the Yang nature found in the natural world.

That was why the healing process was so slow.

"What a strange condition."

Tsunade lowered her head and looked at the shed flesh. This flesh had been contaminated by radioactive elements, visibly blackening before finally turning into a puddle of rotten sludge.

She placed it beneath a special instrument. With its assistance, the flesh was magnified, revealing the utterly destroyed cells within. Her brows knitted tightly together.

"It can be confirmed that there is a strange element in your body, but further research will be needed to determine exactly what it is."

The radioactive traces in the flesh destroyed by Yuu's uranium element had already been absorbed back into his body, so Tsunade could not detect them.

Unfortunately, Tsunade's research focused on the human body. If it had been Orochimaru instead, he might truly have been able to figure it out.