Huldra aren't foxes!
They just happen to look like them.
Freddy twitches when the girl threatens him. Normally Huldra are totally unable to use violence against someone. Unless they're threatened or attacked first (or unless you comment on their tails).
But given how many people are around? Attacking first might not be the best plan...
So instead he turns, sits down on his haunches, and just peers at the young woman for a moment or two before-!
Suddenly he isn't a fox at all!
He's a guy!
An absurdly attractive guy, in fact. An absurdly attractive guy based on Jamie's both conscious and unconscious ideals on what a perfectly attractive male would look like. Freddy has taken the form of the most handsome person possible from Jamie's point of view.
Most people are usually stunned for a few moments when faced with their own personal rendition of perfection.
"Please forgive me," the absurdly hawt guy says. "I had no idea that these apparitions were valued. But you see, even if I leave them alone it doesn't solve my own plight! I've been cursed with the form of that horrible monster and unless I prey on lost souls I'll lose my mind and begin hunting the living."
That sounds terrible!
"So I'm trapped, feeding on the echoes of people that have passed on, trying desperately to avoid taking the life of an innocent," he locks his gaze with Jamie's, his eyes pleading. "This place is like a beacon to these lost souls. If you allowed me to hunt here then I'm sure I would be able to keep my mind."