Denji is a teenager who lives his life as a Devil Hunter.

Aiming to pay off the debt he inherited from his father, he starts hunting devils for the yakuza with his buddy Pochita, a "Chainsaw Devil", while living a tragically poor life.

Just when things seem like they couldn't get any worse, Denji gets betrayed and killed by the yakuza. As Denji starts passing out, he hears someone calling from inside his head...
I offer them a bit of demonic power, 
and they offer to become my slaves...
ما إن قدّمتُ لهم قليلاً من القوّة الشّيطانيّة
...حتّى عرَضوا عليّ أن يصبحوا عبيداً لي
Ich hab ihnen bloß
meine Macht angeboten,
Cuando les prometí
el poder de los demonios…
Les ofrecí poder demoníaco y
decidieron convertirse en mis esclavos.
Me demander mon pouvoir,
Gli ho detto che avrei dato loro
i poteri di un Diavolo
Eu disse que daria poderes diabólicos e
eles se ofereceram pra ser meus escravos...
Я им демоническую силу пообещал…
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