Ao Fukai

The series' hero. The 13-year-old biological son of Renton Thurston and Eureka, technically making him Ao Thurston; he resembles his father during his younger days, but with the hair, eye, and skin color of his mother. His mother one day fell from a clear sky into a bay in Iwato Jima, before giving birth to Ao sometime later. After Eureka was handed over to the American Armed Forces ten years ago, as the islanders believe her and Ao's presence angered their local deity the "Sea Colossus" with the appearance of Scub Coral, Ao ended up in the care of his mother's only friend Toshio Fukai.

Ao discovers the RA272 Nirvash after he unintentionally retrieves his mother's bracelet from Gazelle who was smuggling it for the Japanese Army, and then Gazelle gets him to pilot the IFO, both named the Nirvash by Eureka and created by Renton. Ostracized by the villagers and targeted by the armies of several countries, Ao decides to join Team Pied Piper, hoping to find her. As the son of a human and a Coralian, he has been shown to possess a sort of psychic insight involving secrets, and the ability to see Trapar particles with his naked eyes.