Mito, Offer Up Your Heart (Please Keep Reading!)

Ninjas died when they were killed.

They also died when their chakra was exhausted. Here, exhaustion did not refer to the portion that had been refined, but to the fundamental physical and spiritual energy used to sustain life and generate chakra.

Typical examples were the Eight Gates and Takigakure's secret treasure, Hero's Water.

Both came at the cost of burning away one's life, forcibly drawing out physical and spiritual energy and detonating it all at once like a bomb to unleash an enormous amount of chakra in an instant.

Other than such extreme methods of use,

as long as one did not use too much at once, the body would recover on its own.

Even if it could not return to its peak condition, it would not lead to a swift death.

After repeatedly sensing and confirming it, Toji found that Hashirama's physical energy was still abundant. Even after battling Madara Uchiha for an entire day and using Unmarked Self-Healing to accelerate cell division and mend his injuries, he was nowhere near the point of overexertion or depletion.

Clearly, the root cause of Hashirama Senju's later death was not a problem with his body.

The problem lay in his spirit.

The spirit was an extremely subjective, idealistic form of energy. Even Toji could not accurately determine how much spiritual energy Hashirama had left.

But he could roughly guess that Hashirama was far less open-minded than he appeared.

A man who valued friendship, believed in bonds, and longed for people to understand one another, after personally killing Madara, his lifelong closest friend, suffered an incurable cancer of the spirit and declined irreversibly.

Its name was love.

Longing and guilt gnawed at Hashirama's heart day and night, wearing down his resolve until he finally died in despair.

That was also why, when