In Chainsaw Man, Denji becomes the host of the Chainsaw Devil, Pochita. As Chainsaw Man, he not only gains enhanced combat abilities and regeneration but also possesses a unique ability: when he kills and devours a devil, the concept that devil represents is erased from existence and memory. For instance, if Chainsaw Man consumes the “War Devil,” the concept of war would vanish from human history entirely. This power makes him feared by both humans and devils, as it allows him to permanently reshape reality.
Makima, the Control Devil, seeks to use Chainsaw Man’s ability to erase concepts of suffering and fear — such as war, hunger, and oppression— thereby creating a world free of violence, inequality, and pain. However, achieving this vision requires ruthless methods: manipulating, sacrificing, and killing others to achieve a utilitarian “greater good".