Dr. Kukui is a Pokémon Expert from the Alola region.

Dr. Kukui is a passionate man who lives in the player's new hometown. His area of expertise is Pokémon moves, and is known to take direct hits from them if he thinks he can learn something about them. Together with Hala, he gives the player and Hau their starter Pokémon. Lillie assists Dr. Kukui for her own, personal reasons.

(Source: Bulbapedia)