"I'll just call him Knifewing, that's his kind.

He collects sorcerers. He caught the human before I could get her home and used her as bait and then he caught me.

And I hope she's dead by now."

"Because he treats prisoners terribly?"

"We're not like you. There just is not actually any consequence or limit associated with that."

"Well, that sounds really bad."

"Yes! It's really bad!"

"And the very very dangerous solution would be?"

"Well, going in and making him cut it out. But I'm not sure being fast would quite do the trick by itself and I haven't heard of any magic you have that sorcerers don't that closes the gap and he's more than clever enough to entertain himself around whatever interactions the debt thing has with him if there's any mistake that lets him have an opening, he is very smart."

"I mean if he doesn't know how it works, then as you describe him hooking him into it would destroy him in a matter of hours."

"Does it create debt accounting between pairs of people neither of whom are fairies?"

"No. But if he got a fairy -"

"He's very smart and I have not explained the thing we have instead of debt yet."

Nod.

"I don't think I know enough to be helpful here."

"And you wouldn't be allowed anyway, presumably."

"I'd be allowed to make suggestions, at least."

"There are particular reasons I can't manage it on my own."

Nod. 

"What's the risk if you explain to me how your world works?"

"I think I'm more dangerous to people around me when I'm scared, so there's that."

"I mostly meant what's the risk to you, but okay."

"People deciding to use it. Or being obliged to."

Nod. "I mean, they could promise not to, though I don't know how many takers you'd have for that promise."

"And I know a lot about how to work in my system. I learned from the best. I don't know yours, I don't know how promises have to be worded or anything."