Four Categories

The Four Categories is a proprietary library classification in the Land of Dragons, similar to the Dungy Decimal System. It is one of the oldest ways of categorizing literature in the world, having appeared in the oldest extant library catalogs.

Literature is divided into four categories.

刀部 Dao Classics by Con-Fusion the Legal Sword, a sentient dao who became a con artist and tricked the government into thinking it was okay that it killed people.
死部 Shi All the books about dead people: Historiography (incl. biographies, administration, policy, geography and bibliography)
子部 Zi Masters and philosophers (incl. various scientific and scholarly treatises, books on exercising and diets, and novellas)
呂部 Lu Extermination anthologies all authored by the Cockroach King, Lu Bu the FUBU, and some love poems too