Azuki-Arai is a bean-washing youkai who's best known as one of Kitarou's closest friends. The character was originally just called Mononoke in the early Hakaba Kitaro manga chapters before getting the more specific name Azuki-Arai (literally "azuki bean washer")—though some sources use the alternate name Azuki-Togi ("azuki bean grinding"). True to the name, this youkai's whole deal involves washing azuki beans, which is pretty much their defining trait and where most of the comedic potential comes from in the series.
Content compiled by AnimeList.moe from publicly available sources.