Devastated by Nayuta's death, Denji loses control and unleashes the destructive power of Black Chainsaw Man. Determined to defeat him, Yoru, the War Devil, agrees to sacrifice what she holds most precious to create weapons of terrifying power. But their confrontation takes an unexpected turn with the intervention of the Aging Devil, a formidable entity that wishes to be devoured by Chainsaw Man. Drawn into a strange world where time seems to stand still, Denji and Asa face a new ordeal governed by rules beyond human understanding.