The Japanese word youkai and the Chinese word yaoguai are written with the same characters - 妖怪:

妖 (yō / yāo) – the strange, seductive, or supernatural

怪 (kai / guài) – the mysterious, monstrous, or uncanny

Both terms share linguistic origins, and refer to supernatural beings.

Yet in meaning, the terms have semantically diverged:

• The youkai of Japan now refer to diverse creatures with playful/eerie traits.

• The yaoguai of China remain closer to the classical interpretation of demons.

Cultural Difference: Youkai

Youkai, in the Japanese context, range from natural and regional spirits, to ghosts, animated household objects (tsukumogami), shapeshifting animals, etc.

Sure, there are a few genuinely terrifying youkai (e.g. the kuchi-sake onna).

But otherwise the youkai are more often treated with fascination rather than fear: as the subject of serious cultural studies, as antagonists/villains/do-gooders in urban legends/folklore, and as sympathetic personifications of human figures.

This has led - as one would surmise of Japanese cutesy tendencies - to a funny bulk of moe-ification. My attempt at one such kawaii reproduction here:

Cultural Difference: Yaoguai

But yaoguai, in the Chinese context, seem more restrained to cosmological interpretations (Daoist/Buddhist).

Yaoguai serve as metaphors for chaos, temptation, and karmic deviation; they are mainly malevolent forces, representing spiritual corruption. They tempt, deceive, or consume human beings to further their power or defy heaven.

I love this discovery! It means more cross-cultural history to explore. And I finally understand why wuxia in media often features monks/gods hunting down yaoguai for righteous justice.