Now, I already hit on the question, what can he do to Mac that may "change" her? This one is about Fiona, and it may belong in the Darkfever catagory, but I'll post it here:
(btw, I'm doing my umpteenth reread of the series, and now little things are sticking out)
When Mac eavesdrops on Fio and Barrons through the door, she hears them talking about her and Fiona is telling Barrons to drop it with Mac, blah blah and that Barrons could be a good guy if he wanted to be. Barrons shuts her up ("take a good LOOK at who I am")and there's a protracted silence, a pained little gasp, and more silence. Then Fio is all obedient ("yes, Jericho, whatever you wish")
What did he do? Bite her? This was way back when we thought Barrons might have been a vampire, remember.
We don't hear him voice her. Can he go into her head like he did Mac, but scramble her brains to make her obey?
Lor called Fiona a doormat. Is it because she was so easily manipulated? "Sweet and faithful" is what Barrons called her. He didn't respect her, but used her for sex, on occasion, and to run his bookstore. It probably drove her nuts to have to procure clothes and supplies for Mac.
Fiona also said, in the White Mansion, that Barrons "should have let me die". Just where did Barrons find her? Why did he save her? Could she see the Fae?
It's never mentioned whether or not she was a sidhe-seer. She KNEW of them, and of the sidhe-seers, but WAS she one? An unmentioned escapee from the night the Sinsar-Dubh escaped from the abbey? Her age would have been correct.
Why didn't she earn the privilege of a mercy-killing from Barrons when she'd been skinned? There in the alley, he could have just popped her head off, like Barrons did with Malluce, or K'Vruck did with Darroc (beheading seems to circumvent the whole unseelie eating/healing thing). Why let her suffer?
All these little things are popping up now. Feedback?