Japanese Demon Name Generator

Japanese demons are not one thing. The oni is the closest match to the Western idea: a horned, club-wielding ogre with red, blue or black skin, and its most famous individuals carry names ending in -doji ("child"), an old ironic honorific for a monstrous leader such as Shuten-doji of Mount Oe or his lieutenant Ibaraki-doji. Around the oni sit the wider yokai: the spider-woman Jorogumo, the chimera Nue, the skeleton giant Gashadokuro, and hundreds more whose names are simply descriptions (Rokurokubi, "pulley neck"; Futakuchi-onna, "two-mouthed woman"). A third group is the onryo, human ghosts like Oiwa and Okiku whose plain Edo-period names became terrifying precisely because they sound ordinary.

That gives you three registers to work in. Legendary names lean on heavy, voiced syllables and old titles: -doji, -o (king), Gozen, -nyudo, -hime for a kijo or demon princess. Descriptive yokai names fuse a trait with onna, oni, bo or kozo. Character names for an oni OC or anime-style demon usually take real Japanese name structure and swap in dark kanji readings: kuro (black), yami (darkness), kage (shadow), en (flame), yomi (the underworld), ja (wicked), rasetsu (rakshasa).

The list mixes all three: pull a canon yokai for a tabletop encounter, a fresh oni name for a Demon Slayer-style character, or a full surname-plus-given-name combination for a modern horror story.