I think it really depends on the kind of story you want to tell (I know that seems obvious but just let me finish). Being fully grounded and telling a serious story aren't necessarily contradictory, a lot of media is about Willing Suspension of Disbelief and acceptance of Necessary Weasels simply because the premise is something people want to see.
For a lot of people, I think "magical girls vs evil robot army" is a sufficiently cool premise that you wouldn't need to justify it too much. If you wanted to make a more grounded and realistic story you could come up with a lot of justifications and researched arguments to make it more plausible, but it's realy all up to you. If you have good, complex and believable characters, interesting themes, etc that's what most people are going to care about at the end of the day. You can make people invested in some pretty ridiculous things if you're good enough. You are asking people to meet you halfway regardless when they read your story.
One thing I can think of is that the organization in question DOES recruit young boys as well but they are supporting characters while you mostly focus on the women involved. That way you could have the magical girl story, but not have to really explain why men aren't involved because they are, you're just not really giving them as much focus.
A big question is how obvious it will be. If it doesn't take much Fridge Logic to ask why the heroes are being discriminatory and using child soldiers, and no answer is given, it's going to lead to a Designated Hero problem. However, even implying that there is an answer, whether or not you give it, can go a long way (as long as it doesn't feel like a villain's Hand Wave itself).
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That's also not a bad idea. You could have it where it's technically not just young Magical Girls, but that the group the story follows just happens to be that.
edited 29th May '17 4:42:09 PM by Jokubas
I wasn't quite sure how to word the title, so maybe some context would help explain what I'm asking.
For a past year or so, I've been daydreaming about a Magical Girl story, and I've been wanting to stop being lazy and actually start bringing it to life in some fashion. The short version of what it's about, as copied from my profile:
Not listed: Humongous Mecha, a secret organization of magical girls, and a bit of deconstruction and reconstruction.
As with most of my ideas, it's meant to be on the relatively serious end of the Sliding Scale of Seriousness Versus Silliness. I've been thinking a lot about realistic justifications for most of the details in the setting, such as why it's a Magical Girl story as opposed to a Magical Boy or Magical Old Lady story, how the Bleaksteel first came to power, and so on and so forth.
Thing is that I'm having trouble coming up with such justifications (for example: why the magical girls, who are supposed to be the good guys, are resorting to child soliders when the local Transformation Trinkets aren't bound by age or gender). A lot of the time, it feels like the good guys and the bad guys came from two different stories. And at the end of the day, the premise is basically "magical girls vs. humongous mecha;" not exactly the most serious sounding premise out there.
So I guess the basic question is: when should I try to justify something, and when should I just not address it/just gloss over it?
edited 27th May '17 6:18:16 PM by Yomegami
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