Story
Denji’s a poor young man who’ll do anything for money, even hunting down devils with his pet devil 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!
Chainsaw Man and Jujutsu Kaisen both start with the main protagonist merging/combining with a demon or devil; CM's being Pochita and Denji, JJK's being Yuuji and Sukuna. Jujutsu Kaisen and Chainsaw Man see the protagonists as someone/thing that needs to be eliminated but will let them live on certain conditions, such as fighting against devils on a team or finishing what they started with the merge concerning a demon.