She first appeared in the 2002 film, Lilo & Stitch and has been voiced by Tia Carrere in most of her appearances. She's the love interest of David.
Nani is Lilo's big sister who was appointed as Lilo's sole guardian after the death of their parents who were killed in a car accident.
She is said to be 19 years old in the first film. As a result of having to support herself and Lilo, she is often stressed and busy.
Her busyness often interferes with her friendship with David, who later serves as her love interest. She cares deeply for Lilo and fears losing her to social workers like Cobra Bubbles.
Nani is known for her inability to hold down a full-time job, due in part to the antics of Lilo and Stitch.
She is also noted for being a terrible cook, yet excels greatly in mathematics and chemistry. She does seem to have a crush on David throughout the series.