Setting
Around 1941, all females in the world acquired magical powers.
At first, only a few were able to use magic, and they were isolated or turned into research subjects. Soon witch hunts started all over the world, patterned after the witch hunts of the old.
Soon after, magical girls were appearing in alarming numbers. Since the world was in the middle of WWII, these women who were protected by guns and were advancing the state of the society welcome these new powers. In this society with fewer men, the women busily searched for a new place in the state of things.
The stage is America during WWII.