Looking for a name . . .

In the new novel a character just sprang in there and basically said, "Writer, here I am!" I suppose characters just kind of do that sometimes or maybe it's just to me. I hadn't planned on an extra character. But I don't think she's going to go away anytime soon.

And I need a name . . . She's dark and mysterious . . . seductive with no good intentions whatsoever.

Any suggestions?