Chief Domde Welton: The leader of the Humans of this world, Chief Domde is a key figure in getting the most powerful sword in the game, as are all the Humans, and the Chief is also important in finding the lair of the Humania Big Boss, "Forest Eater."
Natalie Welton: The daughter of Chief Domde, Natalie is part of a sidequest known as the "Kids' Adventure", where you take control of the 5 kids in the game (one from each Civ), and find a special reward at the end.
Frofuus: Frofuus is a realtively quiet character when you first meet him. However, once you discover the "Breezes of the Air" (Wispiaa inhabitants), as he calls them, you can complete the quest, "Learn to Fly", which grants you upgraded Wings.
Dalker: This shadowy fellow only appears at night, next to Domde's house. When you talk to him, he always proclaims his love for the "World where all is shadow, and none can be without." When you discover Darkdem, his quest, "Escorting the One of Darkness", is opened.
Sheesa, the Storeowner: The elderly shopkeep, Sheesa, is just your average, passionate saleswoman running a quite useful store. When you discover the land of Avian, her quest, "The Sky Remedy", will be unlocked, a required quest so you can get your Wings.
Calli Welton: The older sister of Natalie, Calli is not a child. She doesn't even live on mainland Humania. In fact, if you find her on the secret "Shrine Island", she'll give you her reward, the Hugest Wallet, on the spot with no quest.
Leafy Doko: Patriarch of the Doko Tribe, this particular Doko (tree creatures) will start the "Finding the Forest Eater" quest, where he'll work with Domde and you to find the Humania Big Boss.
Sapling Doko: The son of Leafy, Sapling is part of the "Tribe Kids' Adventure", which is a port of the "Kids' Adventure" quest, but with the 5 tribe kids.
Coallel: A lost Rokkae-born explorer, he has found "where he belongs" in the custody of the Dokos. When you find him, he gives the "Explorer's Stone", which begins a fetch quest between the explorers of Openn.
Big Boss - Forest Eater: The "Tormenter of Humania" is the technical first boss of the game. He is found at the end of the "dungeon", Doko Palace, destroying their Grand Shrine.
Chief Windaea: TBA
Ariolan: The "right hand man" of Chief Windaea, Ariolan can be spotted in the sky over Humania, the inside of Windaea's Palace, or even traversing through the harsh environment of Wispiaa, depending on the time of day.
Klepp: A secretive bird basically exiled from Avian, Klepp hides in a cave under an Avian island. The entrance to his cave is blocked by hanging spires from the island's bottom, obscuring it from a glance.
Eutoli: A local chef in the main city of Avian, Eutoli is the first instance of a Chef in Open World. They can make potions and food dishes, things that aren't available in shops. He usually travels around Humania and Rokkae.
Gashal: Gashal is the local shopkeep of Avian, and a good friend of Eutoli's. He sells the most expensive item in the game, the Nexus Block.
Polnatt: Polnatt is the local protest leader against Chief Windaea. He believes he is a much better leader then Windaea, and has more of a relation to the working class citizens. Shame he's only gathered 5 supporters...
Moleis: Leader of the Mol Trible, Moleis is a very popular figure among the Mol people, who live on the underside of the Avian islands. Klepp and the Mols are in very good relations.
Molii: Daughter of Moleis, Molii has a great interest in the world above the Mols; the main land of Avian. In fact, you first meet her before any other Mols, and by bringing her back to her home, you are introduced to the Mol's home.