Sailor Mermaid is the Sailor Senshi of the planet "Mermaid", which was also the homeworld of Aluminum Siren. She was killed by the Sailor Animamate, who took her Star Seed so that she could win Sailor Galaxia's favor. She is mentioned in "Act 54: Stars 5", by Kou Yaten (Sailor Star Healer's human guise), along with Sailors' Chū (the Sailor Senshi of Iron Mouse's homeworld), Coronis (the Sailor Senshi of Lead Crow's homeworld), and Mau (the Sailor Senshi of Tin Nyanko's homeworld).