That was completely and totally unexpected, and weird fairy magic was not the kind of thing that you wanted. Would she drop dead if she didn't keep that promise?
Once she calms down, she runs one hand over her head, long nails gliding across her scalp, and then takes a deep breath. Okay. She can handle this. She's in control. She's got the wits of a hob and the soul of a human, and there's nothing that can stop her.
Her hand is still shaking a little when she walks back over to the wicker man.