She is a restaurant manager who lives near Saffron City. After competing with her twin sister, Rhonda, for the inheritance of her father's restaurant, she decided to give it to her sister after seeing how she handled the situation when their Pokémon were taken by Team Rocket. As she was leaving, her sister hired her as the restaurant's co-manager and her Sneasel as its head chef. After that, their Pokémon cooked delicious food together for Ash and his friends.
Sneasel is Rhoda's only known Pokémon. Its food, while delicious, had a very bland appearance that deterred potential customers. It also had a bad attitude, and would deliberately make Meowth's food taste terrible. After Jessie and James taught it how to put on a good performance, and discovering something on its own, its cooking style became more appealing.
In both Japanese and English, Rhoda's name is a match to her sister's. In the English, there is only a one-letter difference in their names, while in Japanese, both Res and Toran are derived from restaurant.