Shock! Big Sister and I are Going to be Pilots Together?!

Noriko Takaya has spent barely had a month at a training school for giant robots. The school announces they are going to select two candidates to go to the Exelion spaceship for the real missions to fight against an invading mech army. One of the choices is obviously the beautiful and leading senior Kazumi Amano, but somehow Noriko is selected for the second spot! The other girls get jealous that Noriko got the spot, suspecting it's because she was the daughter of the Admiral in a previous mission. School rival Reiko Kashihara feels that's totally wrong, and challenges Noriko to a duel.