Yuna is a young Japanese girl; a tomboy at that, and is a 10-year-old 4th Grade elementary school student who lives on a fictional island off the shore of Okinawa in the Ryukyus called Izayoi Island. Her personality is sweet and outgoing, while still tough and feisty all in all. Living on Izayoi Island, she learns and studies karate, having learned it from her grandpa.