Synopsis for Chainsaw Man
The story takes place in a world where Demons threaten the peace of humans, making them targets to be eliminated. Denji is a young and depressed man who has sold several of his organs and works as a lumberjack and demon hunter to pay off his deceased father's debt. Denji owns a dog (who is also a demon) named Pochita, who has chainsaws and which he uses to do his work.
This is explained because humans can make contracts with demons. After returning home from a job, Denji is called in by a Yakuza to infiltrate a building and assassinate another demon. However, the plan was a trap to kill him as part of a Yakuza contract with the demon, gaining them more power. But Pochita comes to Denji's aid and bonds with him, becoming a half-man, half-demon and acquiring Pochita's chainsaws.
Source: Official Twitter Account
©Tatsuki Fujimoto/Shueisha/MAPPA