Graceling, by Kristin Cashore

Katsa raised her eyebrows.

"I'm not going to wear a red dress," she said.

"It's the color of sunrise," Helda said.

"It's the color of blood," Katsa said.

Sighing, Helda carried the dress from the bathing room. "It would look stunning, My Lady," she called, "with your dark hair and your eyes."

Katsa yanked at one of the more stubborn knots in her hair. She spoke to the bubbles gathered on the surface of the water. "If there's anyone I wish to stun at dinner, I'll hit him in the face."