Buttercup is a member of the Powerpuff Girls.
Buttercup has black hair and green eyes and, like her sisters, an oval-shaped head. She wears a green dress, with a black belt, with black shoes and white stockings.
The "toughest" of the Powerpuff Girls, Buttercup tends to be quicker to violence than her sisters.
Cartoon Network Magazine
After discovering her father's been kidnapped, she works with her sisters and Mystery Inc. to locate him. Although the culprit first appears to be the Mayor of Townsville, when it's revealed to be a disguise for Mojo Jojo, she almost instantly punches him in the face. However, she recognizes a peculiarity in Mojo Jojo's speech, leading to the discovering that this is another disguise, worn by Old Man Withers. With the villain apprehended, she joins her sisters, father, Mystery Inc. and the real Mayor in a pickle party.