After looking at that and reading the summary at Cienna's LJ, she's really like Seishirou. I had said that as a joke once, but maybe it's correct. He didn't feel any emotion when he did terrible things. She's evil in that sense, I think. No curse in the least. Gah, even Watanuki's parents.
They said that xxxHolic would end soon after something was revealed, this was probably it. >_<
[edit] - Actually, now I'm rather doubtful of her paying to save him. But gah, the more I think of it, the more she is like Seishirou. Evil love child he forgot about?