Sayla(制圧, Seira), is the Navigator of the Thunder Beast Pirates. Like most mermaids her age, she has the ability to revert from mermaid form, and a human like form. Having met the Thunder Beasts while she was hiding on Mikoto Island, Hiro begged her to join his crew, however it did not happen right away. After being found and captured by the locals, Hiro and the rest saved her.