Comic book series : Chainsawman

Denji's a poor young man who'll do anything for money, even hunting down devils with his pet devil-dog Pochita. He's a simple man with simple dreams, drowning under a mountain of debt. But his sad life gets turned upside down one day when he's betrayed by someone he trusts. Now with the power of a devil inside him, Denji's become a whole new man-Chainsaw Man!