Pochita is the Chainsaw Devil, embodying humanity's fear of chainsaws. Originally dwelling in Hell, he earned the title "Hero of Hell" through relentless combat against other devils. His unique ability to permanently erase devils and their associated concepts by consuming them instilled widespread dread. This power eliminated historical events and ideas like World War II, nuclear weapons, Nazis, and diseases such as AIDS from human memory. Partial consumption merely weakened concepts, exemplified when eating parts of the War Devil prevented large-scale wars for decades. His actions drew primal fears like the Darkness Devil and Four Horsemen into a catastrophic battle that left him near death. In his diminished state, Pochita resembled a small orange dog with a head-mounted chainsaw blade and pull-cord tail. He fled to Earth, where Denji discovered him injured near his father's grave. Offering his blood, Denji saved Pochita, forging a partnership to hunt devils and settle Denji's yakuza debts. Their bond deepened as Pochita became Denji's sole emotional anchor amid poverty and exploitation. When yakuza betrayed and killed Denji, Pochita merged with his body as a replacement heart, reviving him as a human-devil hybrid. Their contract required Pochita to sustain Denji's life in exchange for witnessing Denji's dreams of normalcy. As Denji's heart, Pochita enabled transformation into Chainsaw Man via a cord in Denji's chest. In this hybrid state, Pochita retained his canine form but lost his head chainsaw and limbs, becoming physiologically fused with Denji. He communicated telepathically, appearing in dreams to warn against accessing suppressed memories or true power. His presence subtly influenced other devils; the Eternity Devil recognized Chainsaw Man's power signature and noted Denji seemed weaker than Pochita's original form. Pochita's true devil form stood towering and humanoid with four chainsaw-armed limbs, a chainsaw head, and dark armored scales. Intestines extended from his stomach like a scarf for carrying or attacking. He possessed immense strength capable of accidentally killing humans with casual movements, speed surpassing devil perception, durability to withstand atmospheric re-entry and massive impacts, and regeneration rebuilding his body from just his heart. Detachable chainsaw chains aided grappling or mobility, and he could generate chainsaws from his legs. Personality defied devil norms. Though initially only barking in his weakened state, Pochita showed profound empathy, especially toward Denji. His longing for human connection—like hugs—was thwarted by his destructive body, leading to accidental deaths. He cherished Denji's dreams and protected him selflessly, refusing to harm innocents for blood even when injured. When Makima broke Denji psychologically to void their contract, Pochita temporarily reverted to his original form. He mimicked Denji's personality to deceive Makima and shielded humans like Kobeni Higashiyama. His moral compass emerged when questioning Makima's plan to erase "bad" concepts, recognizing her vision clashed with his selective erasures for humanity's benefit. Later, Pochita resurfaced during the Chainsaw Man Church arc. After Barem Bridge killed Nayuta (the reincarnated Control Devil) and destroyed Denji's home, Denji's despair allowed Pochita full control. He rampaged against the church's forces, showcasing feral protectiveness. Battling Yoru (the War Devil), Pochita rejected the Aging Devil's flesh despite severe injuries, knowing consumption would trigger a government contract sacrificing 10,000 children—highlighting his inherent heroism. He later regurgitated devils representing "snow" and "bitterness" to restore Denji's memories and will to live, strategically wielding his powers for emotional support. Pochita's existence redefined devil-human relations. His bond with Denji demonstrated devils' capacity for loyalty and affection, while his erasure ability made him pivotal in cosmic conflicts like the Famine Devil's scheme against the Death Devil. His influence endured through Denji, symbolizing fear interwoven with compassion.