In the year 1945, the most terrible creatures in existence visited the earth: bug-like entities soon to be known as Phantom Beasts. In that time of peril, mankind joined together to expel the threat, only to find that conventional weapons were useless and further damaged the earth. It is now 1999, and the student-wide draft has changed the lives of thousands of teenagers across Japan. While unwillingly fighting in an endless war that started before their births, one group of friends will experience the tragedy of death and the bittersweet joy of love as they struggle to survive.