Ariel

Ariel is the rebellious and strong-willed princess in the underwater kingdom of Atlantica. She appears as an ally, party member, and a summon/link throughout the Kingdom Hearts series. She is the youngest daughter of King Triton and his late wife Queen Athena and one of seven sisters. Ariel previously lived at the palace in Atlantica, but, as of Kingdom Hearts II, she has become human and married Prince Eric.