TV-Series
Description
Marinera Rata de Ferro, known in the original Japanese as Sailor Iron Mouse, is a character from the anime Sailor Moon Sailor Stars. She is the first of the Sailor Animamates, a group of Sailor Guardians serving the villain Sailor Galaxia. Her mission on Earth is to collect Star Seeds, the essence of living beings, to deliver them to Galaxia. In her civilian identity, she goes by the name Chuuko Nezu, a pun that combines sounds associated with mice.

She comes from a planet called Chuu Castle. In the manga, it is revealed that she killed the Sailor Guardian of her own home world, Sailor Chuu, and took her Star Seed. Her physical appearance reflects her mouse theme: she is extremely short, typically a foot shorter than the people she targets, and she wears a sailor uniform with mouse ears and a tail. She also has a notable fear of cats.

Her personality is a mix of childlike enthusiasm and intense aggression. She appears to enjoy her work and often selects famous or impressive individuals as her victims, but she can also be lazy when she chooses. Above all, she is openly terrified of Sailor Galaxia and the consequences of failure. Her motivation is primarily fear driven: she seeks to collect enough Star Seeds to avoid Galaxia's wrath.

In the story of the anime, Marinera Rata de Ferro appears as a recurring antagonist across several episodes. She uses a special phone booth she can summon to teleport between locations and to block attacks. Her primary offensive ability is an attack called Galactica Crunch. She eventually discovers the secret identity of Sailor Star Fighter, one of the Sailor Starlights. However, despite this discovery, she fails to secure the Star Seed, and Galaxia, impatient with her failures, kills her as punishment. Her death occurs in episode 181.

Her key relationship is with Sailor Galaxia, whom she serves out of fear and loyalty. She also works alongside the other Animamates: Sailor Aluminum Seiren, Sailor Lead Crow, and Sailor Tin Nyanko, though their interactions are limited. Her development is minimal; she remains a loyal but fearful servant until her abrupt demise, which underscores the ruthless nature of Shadow Galactica.

In the original manga, her role is much shorter. She appears in Act 43 during a concert and is swiftly killed by Sailor Star Healer. Her overall presence in both versions highlights her as a minor but memorable villain whose eagerness and small stature contrast with the grand threat of Galaxia.