Monsters born from moonlight, driven by desire — the Moonlight Beasts.
One night, a girl named Aoi Tachibana is attacked by a Moonlight Beast, but is saved by Luna, a member of the Moonfolk, a race that shares the same origin as the beasts but opposes them.
Through Luna, Aoi gains the power of the moonlight and transforms, managing to repel the beast.
To protect the city from the multiplying Moonlight Beasts, Aoi resolves to fight as a Moon-Armed Battle Princess.
