Princess Mindy (voiced by Scarlett Johansson) is the daughter of Neptune in the animated series SpongeBob Squarepants.  She first appears in the SpongeBob Squarepants Movie, and later in a few episodes.  She is good friends with both SpongeBob and Patrick.  Princess Mindy is a mermaid, so the most important part of her costume will be the mermaid skirt.  From there, some green body paint, a blue wig, and the right accessories will complete the look.

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