Saintias.
They are a special kind of female Saints who are given the task to serve Athena as her personal maids.
Shoko meets Kido Saori, a girl claiming to be the reincarnation of the goddess Athena, who has protected the world from evil since mythological times. However, as the comet Repulse approaches Earth, Shoko must choose either to give in to her destiny as host of an evil goddess, or to rise against it, and protect the peace and justice on Earth as a Saintia.
It's the eve of the Galaxian Wars.
And now, the curtain rises on the fierce battle of the girls protecting Athena.