In A.D. 2031, humans are enjoying a prosperous existence until strange life forms called Hardians appear. They suddenly begin to multiply and assault the human population. As a countermeasure, mankind organizes the N.I.D.F. to investigate the Hardians and protect themselves. A fighter pilot, Aiba Shu, begins to become involved in the battle against the lifeforms. Rurika Yuno, one of Earth's foremost scientists, investigates the Hardians and hears rumors about the Book of a Dead Man. What is the secret of this tome, and what relation does it have to the Hardians? Now, the fight for mankind's survival begins. (Source: AnimeNfo)

2035 A.D. The heads of ancient giant idols were excavated all over the world. Using those twelve stones statues, Humanity had barely overcome the threat of extinction called the Equatorial Winter. But the stone statues had forced Humanity to construct colossal suits of armor as their bodies and demanded that the humans fight each other. (Source: ANN)

Having died in a car accident, Tsubasa Kurata—an otaku from modern Japan—is reborn in the Fremmevilla Kingdom, a medieval world where powerful mechs called Silhouette Knights are used to fight horrific demonic beasts. Born into a noble family under the name of Ernesti Echevarria and bestowed with prodigious magical abilities, he enrolls into Royal Laihaila Academy. This school of magic trains young men and women on how to pilot the Silhouette Knights, prepping them to protect the kingdom from threats, both demonic and human. Ernesti teams up with the twins named Adeltrud and Archid Olter with the goal to create his own Silhouette Knight one day, a feat unheard of for several centuries.

After the death of his elder brother, Ginjiro Yamazaki appoints himself his parents' protector. After transferring to a new school, he gets into a lot of fights. (Source: The Anime Encyclopedia)