Princess Mindy Neptune is the deuteragonist of The SpongeBob SquarePants Movie, the daughter of King Neptune and Queen Amphitrite and is Prince Triton's sister. She knows all the names of the sea creatures. It is also certain that King Neptune will crown her Queen of the Sea one day. She is known to use "Mermaid Magic" to help Bikini Bottomites overcome their fears. There really is not any mermaid magic, it is just fake. Mindy tried to get SpongeBob and Patrick to keep going when they gave up their walk, she tried to convince them that she had "mermaid magic" (which obviously wasn't real), and used it to "turn them into men" by pulling seaweed out of the ground and putting them on their noses, successfully helping them by tricking them into thinking that they were real mustaches. Dennis revealed the trick after SpongeBob and Patrick passed through the trench. Mindy is very beautiful and good-hearted and has a deep love for all the ocean-dwellers.
Mindy has green skin, dark-blue hair, round glasses, a light-green tail and a yellow hair bow. She has light-green skin and wears a golden bracelet. She also wears a pink midriff top with a red heart in the middle.
Unlike her father, she shows more compassion toward her father's subjects. She also encourages Patrick and SpongeBob to continue to Shell City despite that she lied that they became men, which cause them to run into trouble with overconfidence. Her personality is similar to Ariel from Disney's The Little Mermaid.