Merfolk are mythological ocean dwellers who have the lower body of a fish and the upper body of a woman. Folklore tells stories of how they distract sailors with their beauty and hypnotic singing voices causing them to go off course or run aground. Stories mention mermaids dragging humans to their underwater kingdom only to drown them. It is debated whether they simply did not know that humans cannot breathe underwater of if they did it out of spite for trespassing on their ocean. Regardless of a sea nymph's existence or their motives, we can all agree that the mermaid costumes here accurately depict what we think of when we think of water sprites.
With mermaid costumes for both girls and women, they can be sweet or sexy, respectively. They can also be incredibly adorable as is the case with outfits for babies. Girls mermaid costumes predominately feature variations of Ariel from Disney's The Little Mermaid. These feature the purple and teal gown that everyone knows and loves. You can accessorize these with a seaweed boa, an Ariel wand and tiara.