Blue Sapphire is a Magical Girl is one of the Seven Mermaid Princesses.
She is the Mermaid Princess of the Jellyfish Kingdom and has a strong desire to win. Although she is obsessed with winning, she likes to compete fairly, and is faster, more lively, and more energetic than anyone else. However, although she sometimes behaves harshly due to her excessive competitive spirit, when you get to know her, she is also a loyal person who values her friendship with her friends.