Short explaination: A character who will play a major part in the upcoming Jack Salem story.

Long explaination: During the time the City of Ice was a penal colony, there were a lot of very bad people there-- killers, terrorists, career criminals and gangsters, savage carnivores and smugglers. There's also a number of very unfortunate political prisoners and 'undesireables' sent there on trumped-up charges, who usually ended up as prey to the crminals.

But the most feared inhabitant, one that even the powerful gang leaders were hesitant to cross, is the Butcher. A horrible combination of human, wasp and insect dcotor, he was sent to the City of Ice for performing unauthorized 'research' on live (and unwlling) subjects. Once there he didn't miss a beat, and continued his practices in the city, where there is an endless supply of test subjects and no nosey authorities to interupt his work.

Because he is the only actual physician in the city, anyone who wants treatment for serious illness or injury has to go to him. And if they do, they just pray he doesn't decide they'd be an ideal subject for his next experiment.

So while Salem doesn't exactly fear the Butcher, he also would not deliberately antagonize or interact with him. But sometimes things just happen, regardless of what Salem wants.