Today we have the baku, one of my personal favorite monsters from Japan. I've always liked chimerical monsters, they're always so interesting looking and fun to draw. Plus baku look great either as ferocious or as adorable. Today I've gone with adorable.
The baku is a dream-eating monster that devours nightmares and is therefore often beneficial to mankind. Because of this ability, baku were depicted on amulets to protect against nightmares or other sleep problems. Sleepers could even invoke a baku to come and protect them. Like many famous Japanese monsters, it is thought to have originated in Chinese folklore. The baku has been depicted in Japan since the Muromachi period (1336 to 1573). In ancient times it was usually depicted as a ferocious creature with sharp claws, huge tusks and glaring eyes. This appearance helped scare off demons and spirits that brought bad dreams. Of course, the idea of a monster that devoured dreams wasn't only used for feel-good happy stories. There are a few tales of baku that devoured all kinds of dreams, not just nightmares, leaving the poor sleeper restless and mad.
The classical baku is described as looking like a cross between an elephant and a tiger/lion. Today the elephant aspect (or indeed, the entire creature) is instead depicted as a tapir. Why the change? Well baku is also the Japanese word for tapir. The Chinese and Korean names for tapir also correspond to their forms of the legendary baku. Presumably, Asian zoologists thought that the Malaysian tapir's famous proboscis and its 50/50 split coloration was reminiscent of the legendary chimera. Japanese children were taught about the baku by their parents as a playful bedtime story. Young Japanese people growing up in the 20th century grew up hearing both uses of the word, and of course many of them went on to become filmmakers, artists or writers. The baku is, alongside the kappa, tanuki and tengu, one of the most common Japanese monsters to appear in modern pop culture, and so eventually the tapir-baku became the dominant archetype.
For an interesting non-traditional baku, I suggest checking out Satoshi Koh's excellent movie Paprika.