I thought of the story as taking place after the end of a magical girl anime, basically: the team of magically powered teenagers goes to fight the Big Bad, who's been behind all the events of the show so far. And then, in that final battle... they lose. And the Big Bad takes over the world. Five years pass, and that's when the story actually starts.
So, evil is in charge, and life... basically proceeds as normal? The actions of magical girls are strictly regulated. Tyranny and oppression are plentiful, but in ways that mostly don't affect the day-to-day of normal people, so they manage. And the people who used to fight for justice and good are scattered to the winds. I know, a fairly standard setup, but that's where things start.
The novel is about a motley crew of magical girls from different walks of life coming together to pull a heist. This short story, however, will focus on a different part of the world. The setting isn't Earth: it has different geography, history, and culture. It's a world that has always been under threat by creatures of darkness, and has thrived or struggled based on how well its people have handled that threat. As such, there is still a sort of frontier: the edge of explored land, beyond which lies uncharted danger. It's lightly populated by little villages, and not every village has its own magical girl to protect it.
That's where rangers like Boy Howdy come in.
The short story will be about Boy Howdy, a magical girl ranger of the frontier, traveling from village to village dealing with problems. Sort of like a traveling lawman, except she's a magical girl.
(This is subject to change if I write it and it's just not working, but I think this is probably the direction I'll go in!)
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