Denji is the main character in the Chainsaw Man manga series. He inherited his father’s Yakuza debts as a young lad. In an attempt to repay his debt after meeting Pochita, he becomes a Devil Hunter for the Yakuza.
When the Yakuza, led by a Devil, betrays him, he dies, and Pochita becomes his heart. By pulling a rope on his chest, he transforms into the Chainsaw Man. He became a Public Safety Devil Hunter after encountering Makima.