Death Note. Complete Edition by Tsugumi Ohba

A brilliant but disillusioned high-school student discovers a supernatural notebook that kills anyone whose name is written in it, and he sets out to create a crime-free world by executing criminals under a new godlike identity; his campaign draws the attention of a mysterious, world-renowned detective, triggering a high-stakes psychological cat-and-mouse battle that blends supernatural horror, moral ambiguity, and escalating consequences as both sides test the limits of justice, power, and obsession.

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