The Candidate for Goddess Series by Yukiru Sugisaki

One thousand years ago, four planetary systems were utterly destroyed by an alien force. Since then, humans have moved into space colonies and developed humanoid weapons known as Goddesses to defend their last remaining home planet. Five young boys are caught up in the drive to provide worthy pilots to the defense program and must learn to overcome their differences for their sake, and the sake of all mankind.

A thousand years after hostile aliens destroyed four planetary systems, forcing humans into space colonies, five young boys must learn to overcome their differences to become worthy pilots to defend their last remaining home planet.

Battle day is upon Zero and his classmates, as everyone is assigned their own Pro-Ings. To help develop and enhance the class' piloting skills, each member is paired up with one of the top-five candidates at G.O.A., and the two-on-two war games begin! Zero is paired with Erts Virny Cocteau, the top of the top, and the two of them become good friends. But during battle, Zero has a strange vision...

Friendly as ever, Hiead and Zero get into yet another fight, and are put in a detention room that suppresses EX to think about what they've done. Meanwhile, Ernest's concern for fellow pilot Gareas grows as he becomes increasingly reckless in battle. The problem is made worse when the pilots get involved in a battle with thousands of Giseisha.

When Zero and the rest of the candidates progress to Class Two, Clay is faced with the possibility of expulsion. Meanwhile, some students at G.O.A. mysteriously go MIA. Are the disappearances linked with most recent Giseisha attack?