The Guardians of Mars

Taking the Earthly form of crows, Phobos and Deimos are the Guardians of Sailor Mars. It is their duty to aid Sailor Mars in anyway possible. They are not allowed to interfere in any event, aside from a warning, for a crow's warning is not to be ignored lightly.

Their last standing order was given to them by Queen Serenity after she had sent the Princess and all the senshi to the future. They are to watch over the reincarnation of the Princess Mars and ensure that the senshi Mars can awaken. They are to always be near her to help Mars remember who she is, adding to the Norse mythology of Hugi and Munnin (Thought and Memory) who were Odin's constant companions.

In human form, Phobos and Deimos are half human height and look like miniature replicas of Mars. Phobos is always in a black senshi costume without the skirt, and with a grey star instead of a bow on her chest. Phobos is the same, except her costume is grey with a black star. Deimos is also more serious and realistic, but it is Phobos who comes up with the right plans for the occasion. They balance each other out, making them the perfect help for Sailor Mars.

Besides being able to shift between human and crow form, they can merge together in human form to form a body double for the Princess Mars. They can also appear to be Sailor Mars, but they do not have her powers. Their image of Mars is doubled, since they are, in truth, two different spirits. This aids to confuse enemies, so that these enemies might miss them in an attack.

Phobos and Deimos's names derive from the moons that orbit the planet Mars.