I would be curious to know how old the animal was and if it had ever had a bowel movement. Occasionally animals are born not right on the inside and just perish young. Most reputable breeders won't release an animal until it is eating strong and passing solid waste. Seeing as your girl was small enough to to be offered a pinky mouse she couldn't have been old at all. I wonder if she had passed the early, albeit important, milestones of eating and sheeting. Sorry for your loss and hope the experience doesn't turn you off of other species. Kings are a hoot and a half to keep. Just start with a healthy specimen.