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.

Provides examples of:

 * Action Girl - Eri, to our great surprise.
 * Adults Are Useless - They're out of town.
 * Badass Longcoat - "Chainsaw Man"
 * Chainsaw Good - The mysterious regenerating figure uses a chainsaw.The character wielding it is some sense evil (or at least misfortune) personified.
 * Dual Wielding - Of knives. And katanas. But never both at once.
 * Gratuitous English - The title.
 * Katanas Are Just Better - The girl uses a katana, and it's badass.
 * Panty Shot
 * Word Salad Title