Manga: Negative Happy Chainsaw Edge

One day, apathetic high school student Yosuke meets a beautiful girl named Eri. Eri does battle every night with an indestructible, chainsaw-wielding maniac Chainsaw Man. As Yosuke and Eri bond, he eventually joins the fight. Features CG effects by the talents behind the Death Note series. Based on the best-selling novel by Tatsuhiko Takimoto.

A novel turned into a movie turned into a manga. Negative Happy Chainsaw Edge at first seems to be about a school girl with a katana fighting a guy with a chainsaw, then seems to be about death and how to deal with existential despair, then it turns out they're the same thing.

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