Since 2017, an event called “Mundane Halloween” ( 地味ハロウィン, “sober”, “plain”, “boring” or “mundane” Halloween) has become an October tradition in Japan. Participants dress up in plain outfits that are intended to be the drolly humorous antithesis of the often elaborate or cliched costumes everyone else wears on Halloween.

Nevin Thompson, Global Voices: Celebrating “Mundane Halloween” in Japan