Like the player, Bianca lives in the starting town of Nuvema Town, and is also a childhood friend of the player (and soon-to-be-rival). She is described as being 'flighty' by Professor Juniper and Cheren; though she also has a strong side, as shown when she embarks on a Pokémon journey despite her father's strong opposition. This is emphasized in Nimbasa City, where her father disallows her to become a Pokémon Trainer. With the help of Nimbasa City Gym LeaderElesa, Bianca convinces her father to let her follow her dream.
In keeping with the theme of truth and ideals often seen in Black and White, Bianca represents those who pursue truth—this is highlighted when N comments, "Poor Bianca has faced the sad truth that not everyone can become stronger". She often admits that she is not a strong Trainer compared to the player and Cheren; and thinks about what she can do in life (whereas Cheren is seen to ponder about what he should do). Later in the game, she decides to research and learn more about Pokémon with Juniper.
Like the player and Cheren, Bianca receives a starter Pokémon as a gift from Professor Juniper at the start of the game; she chooses the Pokémon with a type disadvantage to the player's starter Pokémon. The player encounters Bianca on several occasions, where she often challenges the player to a battle. After the player has defeated Alder, she will be around to battle them on weekends in Nuvema Town.
"But, I'm... I'm a good trainer who got a Pokémon and everything! I can totally go on an adventure!"
To Player
"Oh... It's OK."
"...It's fine! I'll be waiting for you in front of the lab, OK?
Pokémon Research Lab
"Pokédex?"
"OK! I mean... Yes, professor!"
After Professor Juniper leaves
"S-since the professor asked us, it's OK to go on an adventure, right? I can explore and maybe find out what I want to do in life. I think I'd like that."
Bianca appears as a recurring character in the Pokémon anime. She is a friendly rival of Ash and occasional traveling companion. She is clumsy and hasty, but genuinely goodhearted and cares deeply for her Pokémon and the friends she makes on her journey. Her dad did not allow her to travel for some time, causing her to be slightly inexperienced for her age, but she doesn't take the opportunity for granted. She occasionally runs errands for Professor Juniper, one of which was bringing Ash his Badge case.
In the manga
This section is incomplete. Please feel free to edit this section to add missing information and complete it.
Bianca appears as a supporting character in Pokémon Adventures.
In the Be a Master!! Pokémon BW manga
Bianca is a friend of both Monta and Cheren. Although not much is known about her, she is not as knowledgeable as Cheren. Her starter Pokémon was Oshawott at a type disadvantage to Monta's Snivy. She first appeared with Cheren, and after Cheren's lecture telling Monta his is inexperienced, Bianca says he said too much. She then watches Monta and Cheren battle the Bike Gang King.
Bianca's Oshawott was briefly seen in a flashback of the trio receiving their starter Pokémon and next to her whilst watching Monta and Cheren's battle.
None of its moves are known.
In the Pocket Monsters BW: Meetings with the Legends manga
Pignite was Bianca's first Pokémon that she owned when it was a Tepig. Tepig evolved prior to the time a little girl's Minccino was taken by Team Plasma.
In the Pokémon Pocket Monsters manga
Bianca makes a brief appearance in the very first chapter of Pocket Monsters BW where she along with Black and Cheren go to Professor Juniper's lab to get their first Pokémon.