Naruto: The Dead's Last Wishes, Surviving for Immortality in the Morgue

[Playing it safe] + [Longevity] + [Righting regrets] + [Mastermind behind the scenes]

After transmigrating to Konoha, Su Ye becomes a lowly corpse collector.

In a world where chakra determines one's standing, all he wants is to lie low in the morgue and outlive every powerhouse.

Then he awakens the Underworld Ledger System. By touching a corpse, he can read the deceased's strongest unfulfilled wish.

Fulfill the wish, or fulfill it on their behalf, and he can extract 100% of one of the deceased's core abilities, Kekkei Genkai, or ninjutsu, instantly raising it to the highest level.

For every corpse he handles, whether or not he fulfills the deceased's wish, he can plunder 10% of their remaining lifespan and turn it into his own, granting him longevity.

[Handled Hatake Sakumo's corpse. Obtained max-level swordsmanship: White Fang. Regret: I couldn't protect Konoha's honor.]

[Handled Kushina Uzumaki's corpse. Obtained Sage Body + Nine-Tails Sealing Jutsu. Regret: I never got to watch my child grow up.]

[Handled Shisui Uchiha's corpse. Obtained Kotoamatsukami. Regret: I wanted to pave the way for Itachi.]

…

Years later, the Fourth Shinobi World War erupts.

Madara Uchiha activates Infinite Tsukuyomi, plunging the shinobi world into despair.

Just as everyone believes the end has arrived, a figure emerges from the darkness beneath the Memorial Stone.

With his hands behind his back, he is flanked by the resurrected Hokage of every generation, while every member of the revived Akatsuki stands around him.

Madara: "Who are you? Why is your chakra even more terrifying than mine?"

Su Ye sighs and removes his hood. "I'm just a corpse collector passing through. I've come to collect your body."