Leaf is a young girl from Pallet Town. The local Pokémon expert, Professor Oak, stops her from leaving town one day, saying that she needs a Pokémon for her protection. Upon doing this, Oak takes her to his lab and allows Leaf to choose one of three starter Pokémon, along with his grandson Blue. After spending some time with her Pokémon, and returning to Pallet Town, Professor Oak gives both her and Blue a Pokédex so that they can fill it with information on Pokémon. This is the start of Leaf's Pokémon journey throughout the Kanto region.