A long time has passed since the end of a massive war between humans and monsters. A new type of energy named aer was discovered. When crystallized, this substance became the energy source for blastia, an ancient civilization's technology that provided a wide array of essential abilities for humanity. Despite it's manipulation, mankind still has little knowledge of what exactly is aer. On a mission to eradicate a horde of monsters near the town of Shizotania, a group of knights comes across a strange surge of aer.Yuri Lowell and Flynn Scifo are two new members fresh out of the academy of this knight division. Both are childhood friends who went separate ways, but ended up meeting each other once again while enlisting to serve the Empire.

In the future humankind has expanded and colonized other planets. Then an alien species, Victim, attacks the human colonies leaving only one planet, Zion. In an effort to stop Victim from destroying the last planet a training school, GOA, is set up to gather boys from the Zion colonies and train them to become pilots of the Ingrids AKA The Goddesse… more In the future humankind has expanded and colonized other planets. Then an alien species, Victim, attacks the human colonies leaving only one planet, Zion. In an effort to stop Victim from destroying the last planet a training school, GOA, is set up to gather boys from the Zion colonies and train them to become pilots of the Ingrids AKA The Goddesses, five fighting robots that protect Zion. The boys must possess a rare blood type, EO , as well as a special ability, or EX. Zero (Candidate 88) has just arrived in GOA when he falls into the cockpit of the Ingrid Eeva-Leena. Since the synch between pilot and Ingrid are very sensitive everyone believes the Goddess will kill Zero in an attempt to synch. Just before Zero passes out he makes a full synch with the Goddess. Before he can find out more about the incident, his pilot training begins.

The plot continues and while three new recruits come to the base for training, the whole team comes back to join the fun and defend the planet from outside or maybe inside enemies.

When Imperial forces attack the small border town of Bruhl, Welkin Gunther, son of late General Belgen Gunther, is forced to fight for his life alongside Town Watch captain Alicia Melchiott. Along with Welkin’s adopted sister Isara, the three escape to Gallia’s capital and subsequently join the country’s militia forces. As members of the newly-formed Squad 7, they must work to repel the invading Imperial forces and discover the true purpose of the invasion itself.