Dawn is a character from the Pokémon anime, introduced in Pokémon the Series: Diamond and Pearl as a co-protagonist alongside Ash Ketchum. The princess outfit that she wore is from "Dawn of a Royal Day!" (Japanese: トゲキッス舞う！王女さまのポケモンコンテスト！！ Togekiss Dance! The Princess's Pokémon Contest!!) episode of the Pokémon the Series: Diamond and Pearl.
Dawn has been my favorite female character in the Pokémon franchise.