Global warming is beginning to thaw the ice caps, causing sea levels to rise. Immortal demons that were trapped in the polar ice millennia ago, awaken and begin preying on human beings.

Enter Akira, average high school student who decides to help the world by joining himself with a demon. In theory, a pure young man should be able to control the demon's consciousness and harness its power to fight the rest of its kin, but will it really be that easy?