Aria is a Pokémon Coordinator from Daybreak Town. She is Izzy's biggest rival and they are usually seen battling when ever they are at the same location. After finishing in the Top 8 in the Sinnoh Grand Festival, she traveled around the Johto region to compete in its Pokemon Contests. At the Johto Grand Festival she finished in the Top ?.
While battling Izzy's Silcoon, Cascoon and Silcoon evolved at the same time. Dustox is usually seen training along with Aria's other Pokémon and has been used in a few battles and Contests, notably the Sandalstraw Town Pokémon Contest where she single handedly won the Contest for Aria.