Sailor Lethe guards the River of Oblivion. This river is in the Zero Star of Sagittarius. She comes from the planet Lethe, the twin planet of Mnemosyne. While look a lot like her partner Mnemosyne, there are many things that differ between the two. Physically, Sailor Lethe wears a green dress and her pink hair has four loops in backbefore it goes into four ponytails. Unlike Mnemosyne, her face has a much colder look to it. She is very protective of Mnemosyne and only wishes to live in peace with her twin.