Showing off a belly might be an invitation for petting, or at least acknowledgement of submission and trust, and we all know better than to pet a dog bearing teeth with hackles raised.
Sometimes the dog's hackles would rise and he'd emit a low, rumbling growl, and Paul would watch as the silhouette of a leopard padded past in the distance.
" Hostage" ? The word raised Catelyn's hackles. Hostages were oft exchanged. " Lord Bolton, I hope you are not suggesting that we free the man who killed my sons" .