Baku

The baku in Japanese folklore is traced to the Chinese mo (貘) and appears in Japanese sources from the Muromachi period onward. One popular origin narrative recorded in modern summaries states that the baku was formed from the "spare pieces" left over when the gods created other animals, marking it as a chimera assembled from various creatures and created for the specific pragmatic role of removing nightmares. Early textual attestations (e.g., Sankai Ibutsu, early 17th century) present the creature as a protective chimera against pestilence and evil; the explicit dream‑devouring function appears in later visual and literary sources (late 18th century wood‑block images and Meiji‑era descriptions).

Depictions vary across time and sources but consistently present the baku as a patchwork chimera. Classical depictions emphasize an elephantine head with trunk and tusks combined with other animal parts — Sankai Ibutsu (early 17th century) summarizes it with the trunk and tusks of an elephant, ears of a rhinoceros, tail of a cow, body of a bear and paws of a tiger. A 1791 wood‑block image and Meiji‑period descriptions similarly show an elephant's head and trunk, horns, and tiger claws. Later and modern summaries preserve the elephantine motif while noting regional and artistic variation; the name baku later also came to be applied in Japanese to the Malayan tapir in zoological usage, a semantic shift distinct from the mythic chimera.

Primary cultural ability recorded across sources is the devouring of nightmares: a person (especially a child) who wakes from a bad dream may invoke the baku to eat the dream, allowing restful sleep. Earlier textual contexts (Sankai Ibutsu) attribute protective functions against pestilence and evil; the dream‑eating role appears later in the visual and popular textual record (1791 wood‑blocks, Lafcadio Hearn, modern summaries). Folk cautionary lore warns that the baku must be invoked sparingly: if overcalled and still hungry, it may also consume hopes and desires, producing an undesirable life outcome. The baku is therefore benevolent but not without folkloric risk if misused.