"This… isn't really appropriate," Shizune hesitated, but Tsunade didn't give her a chance to refuse, pulling her to sit down beside her and handing her a set of utensils.
"Don't be shy. The Hokage asked you to sit and eat, so just do it," Tsunade said.
So, even in the middle of the day, Uchiha Seiryu and Tsunade drank and chatted in the Hokage office, their conversation lasting into the afternoon. Eventually, Tsunade relented, agreeing to serve as the dean of the Konoha Medical Academy, and signed her name on the plan.
After sending off this sexy auntie, Seiryu returned to his piled-up official duties.
It was only in the evening that Seiryu returned home.
Once home, Seiryu entered Sage Mode and, only after making sure Black Zetsu wasn't secretly watching, did he open the scroll given to him by the Slug Sage.
Seiryu channeled his Mangekyo Sharingan power and Sage chakra into the two seals within the scroll.
Once the seals were undone, the previously chaotic writing on the scroll rearranged itself into clear shinobi script:
[Descendant of the Uchiha Clan, greetings. If you are opening this scroll after receiving it from the Slug Sage, you must have awakened the Mangekyo Sharingan and mastered Sage Mode.]
[As your ancestor, I must first express my condolences for the important person you lost in awakening the Mangekyo. I know that pain myself.]
[I must also warn you: do not become obsessed with power. The path we chose is full of danger. Only by maintaining absolute calm is there a chance for survival. That's why I never left the full inheritance within the clan. Most of our clan blindly pursues power—I hope you are not like that.]
"This ancestor is interesting," Seiryu couldn't help but smile at the warning at the start of the scroll. What his ancestor said was really uncharacteristic for an Uchiha.
[Since you found this scroll, you must have noticed the Mangekyo Sharingan's overuse leads to blindness. With Sage Mode, you should also have found that natural energy can slowly repair the damage caused by the Mangekyo.]
[You may wonder: can natural energy fully repair the Mangekyo Sharingan?]
[Unfortunately, it cannot. Think of the Mangekyo as a mirror; with use, cracks appear. The method recorded on the stone tablet in the clan shrine—where you use similar-origin ocular power as a crucible to recast the damaged mirror, making it stronger—natural energy can only act as a glue, delaying the mirror's shattering.]
[But don't lose hope. There is a way to use natural energy to promote the Mangekyo's evolution, but the requirement is strict. I don't know which of the three Great Sage Lands you learned Sage Mode from. Their Sage Modes are powerful, but fundamentally, each was created based on the body of a slug, toad, or snake. Even if you master them perfectly, you're left with non-human traits.]
[To use natural energy to evolve the Mangekyo, the crucial point is to achieve a Sage Mode perfectly adapted to the human body.]
[Even though the ratio of natural, physical, and spiritual energy is 1:1:1 in the Three Great Sage Lands, their Sage Modes all contain elements that alter the human body. This is why, after mastering them, you experience bodily changes. When evolving the Sharingan, this aspect is actually a hindrance. Only a Sage Mode perfectly adapted to the human body can succeed.]
[You're in luck, my descendant. I've already finished this step. The method to train the human-exclusive Sage Mode is written later in the scroll. But heed my warning: unless your Mangekyo has a power like mine that can reverse your own state, you get only one chance.]
[The ratio of energies for the most suitable human Sage chakra is incredibly delicate. I can't describe it with exact numbers. However, I've sealed a perfect sample of human Sage chakra within this scroll. But be extremely careful—if you lose balance when synthesizing this Sage chakra, not even the black rods of Mount Myoboku or the Slug Sage's special mucus can expel the natural energy. I only found the balance point after countless trials using my ocular power, before my vision was lost.]
[As your ancestor, I don't really wish for my descendants to seek power through such dangerous means. But if you need it to protect what you cherish, I wish you success.]
[Additionally, I've sealed a portion of my ocular power in this chakra crystal using a transcription seal. If you fail, this ocular power will rewind your body to the state before you attempted the synthesis. That's why you only get one chance.]
After these words came a lengthy method for cultivating the human-exclusive Sage Mode, as well as a special crystal containing the unique Sage chakra.
Seiryu read the cultivation method carefully, and then picked up the crystal.
As soon as he held it, even in Sage Mode, Seiryu instantly noticed how unique this Sage chakra was.
Unlike the 1:1:1 mix of the three Great Sage Lands, this chakra's physical and spiritual energies, and spiritual and natural energies, were in a very special ratio.
"This ratio… the golden ratio?" Seiryu sensed the numbers and was shocked—the three energies were combined in the 1:0.618 ratio, the so-called golden ratio from his previous life.
"No wonder it's so difficult to synthesize." Seiryu massaged his temples. Unlike the precise numbers of the Sage Lands, this special Sage chakra's ratio was an endless, non-repeating decimal, and could only be grasped by feel.