Two short ideas. I'm sorry if someone already suggested something similar, I read some but don't have the time right now to wade thru the nine pages of (awesome) suggestions, and I don't want to pospone this and end up forgetting it.Scenario I
a simpler oneSetting
You come across a group of religious fanatics in a small town, they've all been converted to a random new religion by a prophet who's brainwashed them. Not that it was hard, it's a small village of uncultured people that has raised on it's own in the years after the fallout, they never had any kind of education and are quite gullible, so converting them wasn't much of an issue for the guy.
Now, the prophet: he might either be an asshole taking advantage of these poor fellas to his advantage, a truly nutjob who actually believes all of what he's preaching, or a sociopath that simply enjoys manipulating the weaker of mind.Problem
Case scenario 1, if the guy's mad or a sociopath: incoming mass suicide.
Case scenario 2, if the guy's an ass or mad (in a more barbaric way): he's about to rush them into attacking a town to take it over, loot everything, kill everyone, you know, the regular drill.Outcomes
As usual, you can just let the river follow it's course while you step aside.
A character with enough charisma, speech and picking the right choices might be able to bring back some common sense into the people and make them realize the madness they're about to commit and leave them to their own, send them to a ranger center, what you will.
What about the leader? Perhaps they choose to hang him, maybe you feel pity because he's truly mad (or so you think) and let him go (which might affect you for good or bad in the future).
A character with enough charisma, speech and the right choices might be able to remove the prophet and takes it's place as a leader of the pack. From there on, the possibilities are many.
You kill the leader. Well, the zealots might not like this very much and attack you, or pick a new chosen one of their own and carry on with their actions.
a darker oneSetting
Middle of nowhere.
Nowhere; arid vast waste; middle of a desert; or sorrounded by a mountain range, you choose.
You find a small cottage/farm/house.
A grown man (on his 40s 'haps) lives there with about ten/fifteen children. How did they reach that place? Escaping from bandits? The man answers this very vaguely, and the kids aren't of much help.
Inside the house you find a basement, there's a well that provides safe (as safe as you can find in a nuclear waste, that's it) waters, buckets, and a small farm where they've been raising rabbits. There's also a small greenhouse where they grow their own food (vegetables and such) with a system of small holes in the roof that reach the ground above and allow for light to come in as well as air.Problem
You find out the guy's a pederast. He's not forcibly raping the kids though, he's actually got them to believe it's completely natural and a labour of love. They aren't big enough to know better (the oldest be about ten years old) so it might have stricken them as odd at some point, but now they seem to go along with it.Outcomes
If you kill the guy, the kids won't be able to sustain themselves on their own, they help a bit here and there, but have no idea of how everything works and won't be able to mantain their souce of food for long before they starve.
There's simply too many to take them with you; you don't have the resources, the nearest town/ranger center is too far away and besides it would be too dangerous to travel with them through the wastes. Even if you had enough food to last the journey and somehow were able to make them walk all the way, they'd probably end up dead caught by crossfire, sickness or kidnapped.
leave one of your characters with them though, but that means you'd be losing a companion. And there should be one willing to do this to begin with, so there's also that.
But then again, how would the children take the death or sudden dissappearance of their father (let's suppose that's how they call them)? What if they turn in against you or run away and you aren't able to get them all back? How do you explain what happened to all the rest?
There's really no good outcome for this one, but perhaps you can prove me wrong by thinking of another solution.
Sorry for the clumsy writing, would have liked to polish this, but gotta study