The Empire and the Nebulis Sovereignty have been at war for centuries; imprisoned for freeing a witch, Iska is offered freedom in exchange for taking down a powerful astral mage known as the Ice Calamity Witch.

After their brief encounter, Iska and Alice make an impression on each other and realise they have much more in common than they first thought.

Iska receives a new mission to apprehend the Ice Calamity Witch. By accomplishing the mission, he'll be one step closer to realising his dream of a peace treaty.

A hundred years ago, a drift of astral energy creates a vortex and gives people astral power; as another vortex forms in present times, the Empire and the Nebulis Sovereignty race to acquire it first.

The members of Unit N07 locate the vortex, but discover the Sovereignty has already found it; after Mismis is captured, Iska must fight Kissing to get her back.

Iska and Mismis survive the eruption of the vortex, but the team don't escape unscathed; Alice decides to search for Iska in Ein again.