Rosa from Pokemon
In Pokemon Black 2 and White 2, Rosa (Mei in Japan) is a Pokemon trainer from Aspertia City. She sets off with her friend Nate to collect Pokemon, taking a journey across the Unova region.
James from Pokemon
In Pokemon, James is a member of Team Rocket, a trio that follows Ash Ketchum around trying to steal his Pikachu. If you see James, his mates Jessie and Meowth are usually not far behind.
Serena from Pokemon X and Y
In Pokemon X and Y, Serena is a Pokemon trainer who, along with her Pokemon Fennekin, accompanies Ash Ketchum on some of his travels. She is a kind girl but openly rebels against her mother.
Natural Harmonia Gropius
In Pokemon Black and White, N (full name Natural Harmonia Gropius) is the leader of Team Plasma. He grew up among abused Pokemon, where he learned to communicate with them and grew to despise humans, who he blamed for their abuse.