Peanut Princess first appears briefly in Ice King's Imagination Zone in "What is Life?" She then appears in "Loyalty to the King" as one of the many princesses who are interested in the Nice King. She was first told about the Nice King by Lumpy Space Princess. According to "Princess Day" she is a registered princess, and during that episode she expressed her anger that Raggedy Princess hadn't paid her according to a prior agreement with socks and a pair of shorts.
She is a tan colored peanut. Unlike most princesses, she does not wear a dress. She wears a pointy burgundy- and purple-striped hat with a string holding what appears to be an almond. However, in her first cameo, her hat is blue with one orange stripe.
- The hook on her telephone resembles a hand-cranked wall style with the shape of a peanut.
- Her hat in "What is Life?" is dark blue with a single orange stripe. In "Loyalty to the King," however, her hat is burgundy and has two purple stripes.
- In the title card of "Loyalty to the King," a red heart takes the place of the almond at the end of the string on her hat.
- It can be assumed that she and Lumpy Space Princess are good friends since she was the first to be notified about the Nice King and told her not to tell anyone.