Can you see them?

It's no secret I love Charlaine Harris' Sookie Stackhouse books, and lookee here! My lovely publisher, Gollancz, have given the UK editions some bloody spiffy new covers!

(I've added the obligatory Eric Northman pic*, to round out the set, of course! *g*)

But can you see what's there? I couldn't, not until it was pointed out to me* :-D

See the covers and work out the puzzle here