User blog comment:ARCUSTHEGODDESSOFRAINBOWS/South American Fairy Tales~!/@comment-4598697-20151026124455

You could be the Yara from The Story of the Yara. (The Yara comes from Brazil.) While the story doesn't describe her that well, Wikipedia has a detailed description of what the Yara looks like. Since she is sometimes described as having green hair, you could wear a green wig or dye your hair green (temporary dye would be better since it's only for one day). Her bottom half is either a fish, a manatee, or a river dolphin. If you want to do river dolphin, you could wear pink leggings and decorate them similar to a dolphin's tail. If you want to do manatee, you could try a wider skirt to represent the manatee. For a fish, you could use a mermaid tale of any color. There are also lots of other stories involving the Yara besides the one I listed.