The year is 1944, around when Miyafuji Yoshika joined the 501st JFW to protect Gallia.

The South European nation Romagna is launching a Neuroi counteroffensive with its 504th JFW, nicknamed The Ardor Witches. Its core is made up by the Duchy of Romagna's elite, the Red Pants Unit, but, what is soon becoming evident as the detachment is coming together, is that the members all seem to a bit peculiar, not the least of which the commander. What will destiny have in store for this group of girls...?