They do many jobs in the Bathhouse while employed, such as waiting on the customers, preparing and serving the food, and cleaning the tubs. They are the spirits of slugs. They showed cold faces toward Chihiro Ogino upon her arrival, but became more supportive of her throughout the film, evident by their cheering for her after she helped the Stink Spirit and her successful completion of Yubaba's final challenge.
Some of the Yuna were dressed in hakama and haori (red, divided pants and a white kimono jacket), resembling miko or shrine maidens.
Other Yuna were dressed the same as Lin and Chihiro were.