Ao Fukai (フカイ・アオ Fukai Ao), or more appropriately Ao Thurston (アオ・サーストン Ao Thurston), pronounced as "aʊ", is the protagonist of Eureka Seven: AO. Ao the son of the two main characters from Eureka Seven; Renton Thurston and Eureka Thurston, and the younger brother of the late Amber Thurston.