Negotiations
You send your fanciest rat. One with an elaborate silk hat and a toy soldier's sword hanging at the side. The prince of rats bows before the urchin as if she's a queen. Which, in a way...
In any case, she's delighted. She claps her hands and coos over the smartly dressed rodent just like a real little girl. But it turns out she has her reasons. This. This is what she wants. The rat steps back and loudly protests that it has a master and isn't looking for another. She shakes her head. She's not looking to command rats. She wants to be one when she pleases. Sometimes a girl, sometimes a rat, sometimes a halfway creature like this adorable little thing.
You remember. Yes, there's a thing you can do to make that easier for her. She could force it through without your consent, but it would take a lot more energy. The question is, why should you? A rat-faced goddess running around just means potential problems for you.
When the rat asks the question on your behalf, she makes the obvious response. She's willing to offer an exchange. Half of the raw power she'd have to use if you denied her, an opportunity to change yourself with one of her domains as a mold (with a discount similar to the one she's getting), or a marker for any reasonable favor to be called in at any time.
Interesting.
[ ] Refuse The Deal
[ ] Accept The Deal
-[ ] And take the raw power
-[ ] And take the guided change
-[ ] And take the favor