Mikeosu is a character appearing in Pokémon: Adventures on the Orange Islands.
Season 2: Adventures on the Orange Islands
A leader of the followers of Meowth's Island, Mikeosu believed Meowth was sent to bring happiness and wealth to the island and after Meowth enjoyed the luxury, he put him to the test to use Pay Day (although surprised since Meowth should know that move). Since Meowth cannot use Pay Day, Jessie and James threw money to fool people. Meowth realized Jessie and James were kind to him in this matter, so he left the island and his followers surprised as he continued his journey with Jessie and James.