Boiler was a human, but was bitten by Vaurien Scapegrace at Phoenix Park and became part of the Zombie Horde. He was Scapegrace's ninth victim and the last to be given a proper name.
Boiler later ate a human near the Midnight Hotel, along with the rest of the Zombie Horde. They and went on a rampage, ending up at the hotel. Boiler, as part of the Horde, was killed by the people defending the hotel.