Yomogi Asanaka is a first year student at Fujiyokidai High School. One day, on his way home, he came across Gauma, a mysterious man who called himself "Tamer of Monster".
Suddenly, a monster and giant rotbot Dynazenon appeared in front of Yomogi. He came to get involeved in a battle against monsters with Yume Minami, Koyomi Yamanaka, Chise Asukagawa, who happened to be here with him.