A character in the animated TV show Adventure Time.
Fionna (previously spelled Fiona and also known as Fionna the Human) is a fictional character and the gender-swapped version of Finn who was created by the Ice King in his fan-fiction. In the real world, she was created by series character designer Natasha Allegri in a series of web comics and drawings. She and the other gender-swapped characters appeared occasionally in their own segment of the show. She is usually seen in the company of Cake, her own stretchy companion and also adoptive sister. Fionna’s nemesis is the Ice Queen. She is shown to have an attraction to Prince Gumball and a past with Marshall Lee. Ice King fantasizes about one day making her real and marrying her.