From Bulbapedia, the community-driven Pokémon encyclopedia.
Infernando (Japanese: ブラスケ Burasuke) is the self-proclaimed "fire-breathing clown and street performer extraordinaire" from the episode A Ghost of a Chance.
He is a resident of Ecruteak City and a seller of the infamous treasure detector. His first attempt to sell it failed, as both Ash and Misty walked away from him, Ash smelling a scam. Brock expressed interest if only it would find him a girlfriend, his type of treasure.
Infernando found a sap in James, being able to convince him to buy the treasure seeker with the money Jessie and Meowth gave him to buy food. The treasure seeker was then used by James in both A Ghost of a Chance and From Ghost to Ghost.