Keiko

Keiko is a character of the day who appeared in Hassle In The Castle (EP167). She is a nurse that works at the castle clinic run by Dr. Anna which uses Pokémon to treat medical issues in humans such as muscle pain and wounds.

Keiko escorted Ash and Misty to the castle maze's only exit located in the nearby forest, after Brock and Dr. Anna fell into the strange maze below Dr. Anna's clinic.

(Source: Bulbapedia)