With no memory, Hez wakes up to find that he has traveled back in time to prevent a certain organization from succeeding in destroying the world in the future.

He's the only one who can travel through time. His mission is to discover the secrets of such an organization through the daughter of its boss, a young girl named Mekia, who attends a certain school.

Hez then has a mission to infiltrate the school pretending to be a student and get close to Mekia, discovering the secrets of future attacks to save the world from her cruel fate.