Hmmm, I seem to have missed that agreement within narrative confinement thing.
I will tell them ICly beforehand that she will run the instant it goes physical.
Here is the situation in a nutshell:
What has happened:
Aaron Cohen, sculptor with More Ambition Than Skill or Sense has found in his old family houses attic the Tome of MaHaRaL, item of power that grants Thaumaturgy and a stunt to use craftmanship instead of lore for thaumaturgy. At first not believing what was written there but still curious started reading and in the end managed to summon Merida, a lesser fae and a muse. He bargained and agreed to give "year and a day of his life" in exchange for being famous.
I gave her Incite Emotion(Lasting):Inspiration to represent her ability affect peoples minds. Consequences like "Fevered inspiration", "Compulsive painting/sculpting/whatever" and the like. She creates those, manouvers to gain more tags and gives some to him and uses some to comple him to do more. Quality and crafmanship of his works improved vastly over short time and people started to take notice.
Then he found out that what she meant to do was to compel him to make couple masterpieces and just as he was going big take him away to Nevernever. Artist that previously was moderate at best suddenly makes, in a short amount of time, lots and lots of very high quality stuff and then vanishes without a traces after completing masterpieces? Sure he will be known and famous. But "year and a day of his life" in Nevernever is going to be much longer in our world. He wont be able to enjoy being famous. After all she has "Beware what you wish for".
He panics and uses the tome and one of his sculptures to create golem, to try to stop from taking him away. He has no fighting skills at all so he cant really do that himself. He refuses to let her in and basically locks himself in his, now warded, house. Him and her are in a stalemate. Unfortunately his control of golem is not that good and he mumbles in his sleep. Nonsentient golem takes scared mumblings as order and leaves house to beat whoever it comes accross.
What the PCs know: Someone has been beating apparently random people, including their allies, friends and contacts and they have been asked to help.
IfWhen they talk to Aaron they will hear that she does not fight and will flee at the first sign of violence. She will always negotiate and is true to her word, exacly her word, no more and no less.
The first time they'll meet her is probably just outside his house. He'll do the name and little will summoning. I understand it is basically like sending a "come here please" textmessage which doesnt force her but gets her attention. He'll then retreat to house and refuse to speak to her.
So she will be unprepared for PCs at the first meeting only. After that it will probably be in a park(she is summer), midday/afternoon with a lot people having picknic, walking dog etc. To discourage fighting.
She'll at first ask them to steal a specific letter that is protected by strong threshold and very little else. No monetary value but huge emotional value to its owners. Stealing from elderly widow that one of the PCs know, a precious love letter from her deceaced husband? That should make them at least hesitate a bit. Of cource they might not know about this beforehand, depending on the negotiations
In exchange for even to consider negotiations for fine tuning Aarons time spent away. In exchange for that she want a favour from them, to be collected later.
Ways they could solve it that I can think of:
*Do as she wants, have Aaron be gone for year and a day and not much more, owe her one favour. Gain possible ally and I can use that favour for plot later.
*Manouver smartly and corner her in a fight. Force her to keep him only that year and a day. Gain possible ally and enemy.
*As above but force her to end the deal with Aaron completely. As he is not famous yet neither has fulfilled their end so it might be possible to break it. He looses his skills and interest wanes. He still has the tome and might try something else later. She might hold a grudge for a while.
*Do nothing. When Aaron eventually returns he will be somewhat pissed about that. Gain enemy at much later point. Maybe only a small complication by them, but at suitable point that can be enough to make things interesting.
*They think of something of complete different and I will roll with it. Will be interesting.
PCs are strong in physical conflicts and she is strong in social conflicts. Unless she bring a lot of backup she will loose straight fight and probably win negotations unless players seriously outmanouver her and use those fate points. She will be at 3 vs 1 in social so it is possible for players to manouver around her even though their social skills are much lower than hers.
About that is there way to balance different numbers per side other than lesser side having much higher skills?
This will be the first scenarion of the campaing and only I am familiar with DF world. Point is to intruduce the world and the system. Physical conflict(golem fight), conceding(golem will concede), social combat(first negotation), freedom of choice and I will roll with it(what ever comes after first meeting her). Also supernaturals are individually almost always stronger than mortals, so play smart and know what you are up against. Sometimes there is no easy solution.
That is way more text that I though it would be.