Nope, not a book about demons, but something like a cross between possession and obsession - specifically, the dangers of obsession in my line of work.
Two Literature professors teams up to uncover what they think is a secret affair between two Victorian poets - one of whom is married. It's a kind of literary sleuthing, but of the academic kind, unlike The Eyre Affair which was just plain fun spoofing.
No, sad to say, this literary sleuthing is closer to the real thing - but its ntot the kind of literary scholarship I'm really interested in. The textual stuff is fun, but I don't have enough interest for the kind of detail oriented work this requires. The long and short of it is that the contemporary scholars end up tracing the steps of the lovers and having an affair themselves (a kind of history repeating itself I suppose). What I found most interesting were the 'samples' of writing by these two Victorian poets - all of which were created by Byatt. But it's a long read, and there were times I had to force myself to keep at it, so unless you're a Victorian buff, I wouldn't necessarily recommend it.