Fumario Esron was the male whiterat Chief Executioner of the city of Anak. As a member of Hellgate Prison's upper staff and one of two commanders of the prison, he was well versed in the arts of torture, and executed those sentenced to death by the Lords Common and Lord Mayor of Anak.
He was going to have his understudy, Coruco, carry out the execution of Dran Boldstripe, but the badger managed to avoid the death sentence, and the two executioners' talents went unneeded.

Fumario seemed to see Coruco as a son of sorts, and enjoyed the younger rat's companionship and their shared love of brutality immensely.

Fumario owned a variety of killing tools, but he seemed most fond of his boar spear, a weapon he bought on a peccary hunting trip in Paalau.

His surname, "Esron", is not a Poruugan noble name and was a personal invention to appear of greater status than he actually was. His freeholder father had paid a master forger to forge documentation claiming he and his family to be of noble blood, from "House Esron of Nycaras."