Diyu is referenced in Jackie Vs. AI at the dining-hall scene of the council_of_eight_immortals in Ch6. Cao_guojiu, the Council's bureaucratic conscience, holds up his jade tablet and remarks that the methodology of Liminal is structurally indistinguishable from the Sixth Court of Diyu — the court that processes those who lied while alive. The room laughs, then stops laughing. The comparison is meant as a joke and lands as a diagnosis.
More structurally, Diyu is the negative image against which the books' redemption logic operates. The methodology — are you worth amplifying? — is shown as a pre-mortem version of Diyu's post-mortem audit: the soul is read while still in the body, scored, and sorted. The horror, the Council notes, is that Diyu at least waited until you were dead. The new institutions do their reading in real time. Anna's nine floors underground at liminal_studios are the books' literal rendering of this — a child placed in a building that processes her like the Sixth Court, while she is still small and breathing and seven days from her brother.
Diyu is a syncretic construction. It draws on the older Chinese underworld of the_yellow_springs (Huang Quan) and on Buddhist Naraka cosmology imported from India in the Han and Tang dynasties, eventually fusing into the ten-court system codified in the Yuli Baochao (Jade Record) and elaborated through Tang and Song-dynasty popular literature. Each court has a presiding king, a register, and a specialty: the First Court inducts; the Sixth handles deception; the Tenth, presided over by yan_wang himself, returns the soul to rebirth via the bridge of forgetting and the old woman Meng Po's broth.
The bureaucratic character of Diyu — the registers, the magistrates, the receipts, the processing — is one of Chinese mythology's most distinctive contributions to underworld imagination. It mirrors the imperial Chinese state's own administrative apparatus, projecting it onto eternity.
Hell as paperwork. Diyu is administrative, not theological — a clearinghouse with judges, registers, and procedural rights, not a permanent damnation.
Ten courts, ten specialties. Each court processes a category of life — the Sixth handles deception, the books note, and the parallel to the_methodology is exact.
The bridge of forgetting. Souls return to life via Meng Po's broth, which erases memory. The books treat this as a quiet contrast to halo's opposite operation: erasing memory while still alive.
Pre-mortem audit. What horrifies the Council is that modern methodology runs Diyu's logic on the living — the audit no longer waits for death.