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Seabook Arnou is a mechanic engineer who lives a pacific life within his home colony of Frontier IV, however all of this will change when the "Space Pirates" known as the Crossbone Vanguard will attack Frontier IV in an attempt to take the colony as their home base. Much to his surprise, Arnou will learn that he has strong ties to the conflict, not only his mother has heavy involvement with the Gundam Formula 91 project, but his childhood friend Cecily Fairchild seems to be an important target for the Crossbone Vanguard. Seabook will have no choice other than pilot the Gundam designed by his mother, and attempt to put a stop to this growing conflict.
Frederick F. Brown is a mobile suit trainee in one of Zeon's schools, but always had a hard time keeping up with everyone. Ten months after training hard, he's thrust into actual combat for the first time together with Zeon's declaration of war. He becomes witness to the horrors and atrocities associated with war first hand as he fights to stay alive.
In the future, Earth is split into three factions: Dorssia, an empire bent on world domination; ARSUS, a military alliance; and Jiro, a collection of neutral states with colonies across the galaxy. On one such colony, Haruto Tokishima lives a carefree life at Sakimori High, where his greatest concern is mustering the courage to confess to his childhood friend, Shouko. His idyllic life is broken, however, when a team of Dorssian super-soldiers, led by the enigmatic L-elf, assaults the colony to retrieve the 'Valvrave', a mobile suit secretly being constructed there. In the resulting chaos, Haruto watches as Shouko disappears within a laser’s blast; enraged, he climbs into the now accessible Valvrave, and defeats the Dorssian army after forsaking his humanity to the machine. Haruto pledges to protect the colony, but can he come to terms with what he's given up to gain such power?