Broke young man + chainsaw dog demon = Chainsaw Man

Denji was a small-time devil hunter just trying to survive in a harsh world. After being killed on a job, he is revived by his pet devil Pochita and becomes something new and dangerous--Chainsaw Man

Having been forced to kill a friend, Denji finds that his brain has turned to mush from despair. Without the motivation to keep going, he seeks help from Makima. But Makima is not what she appears, and Denji's pain is only just beginning.