As soon as he entered the office, Shinji could tell something was up.
Everyone was there, but Kakashi looked a bit tired and was dripping eye drops into his eyes.
"What's wrong, sensei?" Shinji asked as he walked towards Hiruzen.
"Oh, senpais are here too." The latter sentence carried a slight teasing tone from Shinji.
"Alright, Shinji, I called you here because there's something we need to confirm." Hiruzen quickly spoke up.
If he didn't speak, Tsunade would have already started a rampage here.
"Confirm?"
Shinji looked surprised, this was unexpected.
"That's right, Fugaku has a theory, but he's not certain." Hiruzen nodded.
A theory, huh? It seems they've found something.
Shinji subtly glanced at Kakashi. He probably hadn't told Kakashi yet, as who would believe such a thing?
That was someone who had been dead for nearly a decade.
"What do you need me to do?" Shinji was curious, especially since Tsunade seemed to have already examined Kakashi.
"I heard you can use Yin Release." Tsunade said.
This was the reason Shinji was called. She herself couldn't use Yin Release, and Jiraiya had recommended him after hearing about it.
"I understand." Shinji nodded.
It was most likely Jiraiya who had mentioned it.
"It's best if you understand. The current stage requires us to compare whether the Yin Chakra contained in Fugaku's eyes and Kakashi's eyes are consistent."
Hearing this, Shinji couldn't help but sigh, they were all intelligent people. Since there was suspicion, comparing the ocular power of two Mangekyo Sharingan would suffice.
"No problem, but it will require the use of Fuinjutsu. Is that alright, clan head Fugaku?" Shinji looked at Fugaku, as this involved a secret of the Uchiha clan.
Fugaku pondered for a moment, then nodded firmly. He had proposed the suspicion, so it was only appropriate for him to be involved.
"Alright, then I'll prepare first."
Seeing this, Shinji said no more and went to the sofa, pulling out two Chakra test papers. Ordinary scrolls wouldn't work, as these needed to be placed directly over the eyes.
Shinji then pulled out a paintbrush he carried, his hand not stopping as he swiftly drew two papers with characters.
"You brat, you can even use Yin Cursed Seals?" Jiraiya looked at the characters Shinji drew, his face filled with disbelief.
"I've been studying it, and I've made some minor achievements." Shinji waved his hand.
Fuinjutsu was a treasure. What he had learned so far was enough to find a corresponding Fuinjutsu for any purpose.
Tsunade twitched her lips, that sounded quite punchable.
"Alright, Kakashi, Fugaku-senpai, please step forward and close your eyes." Shinji picked up the two talismans and spoke to Kakashi and Fugaku.
Seeing that both were ready, Shinji used Chakra to adhere the papers, then placed them over their eyelids.
After seeing that the Chakra test papers were adhered, Shinji withdrew his hands and began to form hand signs.
As Shinji formed the signs, those around him saw a very faint aura of Chakra emanating from his body.
Then Shinji pressed his hands onto the two test papers and closed his eyes. His attention was entirely focused, and the runes on the Chakra test papers slowly spread out. Soon, they covered one side of Kakashi's and Fugaku's faces.
Everyone's breathing involuntarily slowed down, as Shinji, Kakashi, and Fugaku seemed to have entered a state of bunk.
However, Shinji's expression was not that relaxed, as these were Sharingan.
To think that a Yin Cursed Seal could directly probe them was, in the end, a bit presumptuous.
Without further hesitation, black threads began to emerge from his hands, converting into the purest Yin Chakra through the Yin Cursed Seals and entering the Sharingan.
Tsunade looked surprised. This kid's Yin Release had actually reached such a level?
At this moment, Shinji, facing two different Mangekyo, couldn't help but marvel. The Sharingan truly deserved to be one of the Three Great Dojutsu.
His Chakra, transformed into countless subtle sensory tendrils via the Yin Cursed Seals, simultaneously perceived different sights.
On Kakashi's side, there were countless overlapping different space fragments, while on Fugaku's side, it was as if time was rewinding. The entire process was like a fleeting glimpse.
Fortunately, he wasn't trying to explore the mysteries of the Sharingan, but simply expanding the range to check the amount of Yin Chakra in both eyes.
Finally, all sensory tendrils retracted, and Shinji obtained the specific information.
"Hoo—"
Only then did Kakashi and Fugaku simultaneously gasp.
"What's wrong?" Hiruzen quickly stood up.
One was an elite Jonin of Konoha, and the other was the head of the strongest clan. He couldn't afford any mistakes.
"Nothing." Fugaku covered his eyes, looking at Shinji with disbelief.
Kakashi was the same. He could feel that his eyes no longer burdened him as much as before.
"Thank you." After a long pause, Fugaku bowed to Shinji.
This gesture left Tsunade and Jiraiya beside him utterly bewildered.
Shinji waved his hand. "It's nothing, just a bit of Yin Chakra. Since I wanted to probe, I had to pay a little price."
During this probe, much of the Yin Chakra he had just created had remained in Kakashi's and Fugaku's Sharingan. At the very least, Fugaku's Mangekyo wouldn't go blind so easily before exhausting his Yin Chakra. Of course, this was limited to that right eye.
"I will take out some items for compensation when I return." Fugaku said with a solemn expression.
This gift was too significant.
Hiruzen raised an eyebrow and stated, "No one is to speak of what happened today."
"Yes."
Even Tsunade and Jiraiya now understood.
"Kakashi, I want to ask, when you first had the Sharingan transplanted, was it like this? Did using Chakra require more than forty percent of your total Chakra?"
"What?"
At Shinji's words, everyone in the office looked at Kakashi in astonishment.
Forty percent? Or even more?
This was no longer a simple number. In other words, it meant that the Chakra consumption of the Sharingan was already debilitating Kakashi. One must know that in a ninja's battle, the amount of Chakra determines the outcome of the fight.
Although there were other factors, the abundance or lack of Chakra also determined the ninja's potential.