Princess Lana of Eferhild
Lana is the main character and the second daughter in the royal family of Eferhild. Eferhild is a matriarchy, meaning that the throne is inherited through the female line, however being the second daughter, she is not expected to rise to power. The story starts with her being betrothed to Prince Halim of the desert nation Abdul-Bari, but Lana isn't happy about the prospect of being shipped off to live in the desert for the rest of her life. Given that more attention is given to grooming her sister for the throne, Lana didn't always get a lot of attention growing up. She often likes to sneak out into town or spend time in the sanctuary. This second fact is how she was one of the first to know the Earth Gem was stolen, and so she runs away on her own, hoping to catch its thief.
Nathan is a knight of Eferhild Castle and originally from the country of Tryamon. At age eighteen, he became a knight of Eferhild because he was determined to protect Lana after an encounter they had when both were much younger. After Lana goes missing, Nathan goes out on his own to find her and ends up accompanying her and Gwenna when Millicent distracts Prince Halim so Lana can escape. Nathan is loyal to a fault and good with people, since he grew up with eight brothers and sisters. He never had much romantic experience, however, so the many times they have to travel under the guise of a married couple leave him flustered.
Gwenna is a fairy from the country of Tryamon, where fairies are quite commonplace. When Lana encounters her, she is living with the medicine woman Millicent, pretending to be her granddaughter, since a fairy's human form perpetually resembles a human child. Like all fairies, Gwenna is capable of communicating with animals via the fairy's unique language, and she is often tailed by a young wolf cub named Mio-dine (literally 'Wolf-animal' in fairy speak) who is extremely protective of her. When Lana and Nathan escape from Millicent's house in order to elude Prince Halim, Gwenna ends up traveling with them.
Skye is an Amazon warrior woman that Lana, Nathan and Gwenna meet when their ship capsizes and they end up stranded on a remote island. The Amazon society is in an uproar because someone had come and stolen a precious weapon of theirs, and Nathan suspects it's the same person who stole the Earth Gem from Eferhild and the Fire Gem from Abdul-Bari. Skye at first has them thrown in jail under suspicion of being the thieves, but later lets them out when the queen of the Amazons is found dead and it's obvious that it couldn't have been them that did either. Skye ends up traveling with them, determined to find the culprit and avenge her dead queen.