Read this book quite a while ago. Details are a bit sketchy, any help would be appreciated.
Two people, one male, one female. I think that they meet up in the beginning of the story. The male is "bonded" to a creature who reminds me most strongly of the bears that are commonly associated with the Grateful Dead. He explains at one point to the woman that only men can be bonded to the bears, any women that have tried have...died? gone insane? Can't remember. Part of the bond between them is that he gives the creature some of his blood every so often.
A majority of the story revolves around them finding and travelling through what sounds like an extraordinarily large warehouse left by a race that came before.
Near the end of the book the woman discovers that women can bond with the GD bears, but their bond is not centered around blood but something else (that I cannot remember).
That's it. Any ideas?