Set in a slightly futuristic world where Earth has been invaded and is at war with aliens from another dimension called the Nova, the story follows the adventures of a Japanese boy named Kazuya Aoi who enrolls for training at a special school for genetically modified girls called Pandoras who battle the aliens, and their male partners, called Limiters, who use a special power called "freezing" to limit their opponent's mobility. (myanimelist.net)