God first appears as a cat bearing distinctive facial markings that mirror the Yin and Yang symbol, encountered by Rinne Amagane moments before her death. Upon Rinne's arrival in Hell, God manifests in a humanoid form: a small, bespectacled man marked with a prominent 'G' on his forehead.

When questioned about his presence in Hell, God counters with the rhetorical statement, "Don't you all say 'God is dead'?" He serves as an expositional figure, unveiling truths about Hell and the characters. God reveals that the River Styx Academy and Destinyland exist solely within the mind of Abel (Ryu Kutou), not as a true afterlife. He attributes humanity's belief in Hell as a literal place to the pervasive saturation of Abel's imagery across centuries of religion and art.

God crucially uncovers Rinne Amagane's identity, disclosing she is the reincarnation of Eve, mother to Cain (Helvis) and Abel (Ryu Kutou). This lineage explains Abel's manipulation of events to draw Rinne into Hell, motivated by his desire for reunion. God further details Abel's grand scheme: Abel created Steela, a being embodying the power of Nothingness, intending to use her to annihilate all souls and permanently halt the cycle of reincarnation. This plan stems from Abel's millennia of resentment and madness following his murder by Cain.

During the climactic conflict instigated by Abel, God contextualizes the battle between the embodiment of collective negative energy (manifested as the giant Seven Deadly Sins) and the positive willpower of Hell's inhabitants rallied by Rinne. He observes the resolution where Steela sacrifices herself to destroy the consolidated negative energy, transforming into a tree-like structure resembling a crucifix. God's involvement then facilitates Rinne's graduation and return to the living world. Her memories of Hell fade upon awakening in a hospital, though a sense of residual connection persists. This is evidenced when Rinne later encounters a human incarnation of Steela in the mortal world.