In the era when humans expanded their living areas and their own desires to the universe, people seeking freedom immigrated to the universe to live. Their wisdom gave birth to a developed civilization, which unknowingly turned into a threat to the earth. In the year 0156 of the Universal Calendar, the Earth Federation Government experienced the fourth contact (4thnote) with the grandmother planet Grandimas in history. It was also from this year that the confrontation between the Federal Government and the [People of Medus] officially kicked off. The war is endless, and the sacrifices are increasing... In order to open up the war, the Federal Government sent a heroic young man to join the war. The young man's name is Subaru Ichinose. He is not only handsome and has excellent grades, but also the ace pilot of the space battleship [Tiramis]. The hope of all mankind rests on him. ——However, he is actually a "squat" who has difficulty integrating into the collective life on the Tiramis ship and locks himself in the cockpit of the special machine "Durandel" all day long...