Luca is a non-playable character in Final Fantasy IV. She is the princess of the dwarves in the Underworld, and the daughter of King Giott. She also appears in Final Fantasy IV: The After Years as a playable character.
In Final Fantasy IV, Luca has quite a different look from the other dwarves by wearing a pink dress and having her hair up in pigtails. Like the other dwarves her face is obscured, showing only her eyes.
In Final Fantasy IV: The After Years, she has a radically different look, wearing a pink shirt and matching pants, with a matching visor. She sports red-brown and orange bracers and boots, goggles around her neck, and a mole on her cheek. Unlike in the original game, where her hair was brown, her hair is light red.
Luca is a tomboy, who enjoys engineering, as and works as Cid's apprentice in Final Fantasy IV: The After Years. She is one of the few female characters who isn't a magic user, serving as a physical fighter. In The After Years, it is stated she has a crush on Palom, one that she wants to keep secret. She is strong enough to put her feelings aside for more important matters, and gives her approval when Leonora states she has fallen for him. Luca is fiercely protective of Calca and Brina, refusing to let Rydia harm them and fending them off alone when the dolls go berserk and turn on them, and refusing to even let Cid look at their mechanics, claiming they're too fragile for him, who is used to airship engines.