(This is actually a gender bent version of my AT character Prince Fermata.)
Falsetto is the ruler of the Music Kingdom. Although, subject to many wardrobe changes, Falsetto usually resembles a violin.
She is one of the oldest princesses of Aaa, having been "born" after the end of the Mushroom War. Falsetto has ruled quite peacefully over the music kingdom with little trouble, although lately there have been visits from a certain mischievous vampire.
However, like music itself, Falsetto is subject to drastic changes of mood, quickly angering, and then becoming quite cheerful at the drop of a hat.
Despite being one of the oldest princesses in Aaa, she's prone to childish tantrums, which cause her usually pretty voice, to resemble an untuned instrument.
Adventure Time (c) to Pendleton Ward
Falsetto, the Music Princess (c) Lillium Stargazer