One day, 16 year-old Mikuri Tomokazu has a strange dream, in which he sees a young girl fighting against her enemies. In the dream world, Tomikazu possesses a strange power and endows them upon the girl, who then repels her enemies.

Tomokazu is astonished by the dream world, his strange power and by the mysterious girl who wages war. On top of all that, when he wakes up, he finds the girl from the dream next to him! All of a sudden, the weird girl Mone, Tomokazu's older cousin Nanase, and his classmate Mizuki, begin to participate in the battles of the dream world!