Noctis Lucis Caelum,the protagonist of Final Fantasy Versus XIII, is the last heir to the Caelum Dynasty, which rules over the only remaining that controls the Crystals. Noctis attempts to protect his city-state against those who seek to conquer it and take the Crystals by force. Nomura has compared Noctis's family to the modern-day . The color of his eyes have been shown to change from blue to crimson during battle; according to Nomura, the color changes are both intentional and significant.Noctis's full name is Latin for "Light of the Night Sky,"and his nickname is "Noct".

Noctis wields many weapons, ranging from swords, spears, and lances to guns. He controls them with telekinesis (through the power of the Crystal), using them for both attack and defense. Nomura has stated that each weapon has a different usage and is not directly limited by normal standards of attack; for instance, some weapons are also usable as shields (as seen in the trailers).Noctis also has the ability to teleport or to suddenly move at a high speed, though it is unknown what role this skill will have in the actual gameplay.

Noctis's personality is different from any other character in the Final Fantasy franchise (including that of of Final Fantasy VII and of Final Fantasy VIII) and is one that Nomura had wanted to try out for a long time.In the past, protagonists were given strong personalities while distinctive ones were delegated to the supporting cast, but Nomura states that Noctis's idiosyncrasies mark a departure from this tradition.Although his character is said to be hard to define given his complexities,a good measure of his personality can be sensed from his first meeting with Stella.Noctis hides his shyness underneath a façade of coolness in front of him, which creates a cold and unsociable impression.However, he smiles and acts more openly around his friends, a testament to Nomura's statement that "[Noctis] is not the least bit a silent, gloomy little boy."

Stella Nox Fleuret , a young woman with blonde hair, is said to be the princess of the Fleuret family of the country Tenebrae (Latin for "darkness") and an enemy to Noctis, though her allegiances are under suspicion.Stella Nox is Latin (albeit incorrectly inflected) for "Night Star." Fleuret is the French name of the fencing , a direct reference to Stella's weapon of choice, a . Like Noctis, she is able to materialize weapons from thin air, as she is shown summoning her rapier from a rune similar to one used by Noctis to summon his sword, though Stella's rune is golden while Noctis's is blue.

Like that of Noctis, a good measure of Stella's personality can be sensed in her first meeting with Noctis. For instance, in their discussion about the power they share (defined as a special ability to see the "light") and its connection to an old legend, Stella is very open about the matter while Noctis seems reluctant to talk about it, suggesting that they keep it a secret. Stella is described to be ladylike and extremely polite but direct in her manner — a reflection of her proper but strong upbringing. She acts according to her beliefs, and doesn't shy away from problems.Nomura states that she will be the first to stand out from other female characters in the Final Fantasy franchise, although it is not specified how.