Penny is a character who first appeared in Pokémon Scarlet and Pokémon Violet. She attends the same Academy as the player character and is in their grade, making her a classmate of theirs.
Under the alias Cassiopeia, she is the big boss of Team Star, however she also plays a decent role in the story of both Scarlet and Violet as a main character and one of the player's best friends alongside Arven and Nemona.