In the near future, during the colony war, a girl was save by a little boy when a space station was attacked by terrorists in which the girl lost her parents.

A few years later, the girl joined her grandfather's military school. There she met a young man that looked similar to the boy who saved her... but just when she was prepared to enter the school compound, she sees a 'terrorist' lurking around which is actually a terrorist demo under the school command and so the story begins...

[Source: AniDB]