In the magical Sword World, the land of Alantia enjoyed a peaceful existence, until the evil king Ezekiel conquered the land with the help of his demonic minions, and established a tyrannical regime. However, the legend of the Blue Star, a miraculous warrior who would liberate Alantia, continued to live. The last survivor of a powerful race, a young girl named Erina bravely ventures against Ezekiel's forces, in a desperate attempt to fulfill the prophecy.