It is Ukobach's role to never let the fire of hell's cauldron to burn out. The best way to keep the flame lit is by fueling it with fallen warriors of the battlefield. Therefore he will always appear at the locations where war has occurred to collect an endless supply of corpse.
In de Plancy's 1818 Dictionnaire Infernal, Ukobach or Urobach is described as a "Demon of an inferior order." He is shown with a flaming or red body, large eyes and ears and often a pan full of coals or hot poker. He is said to be the inventor of fireworks and the art of frying foods. He is charged, by Belzebuth, to maintain the "oil in the infernal boilers" which is made of the blood of the damned, "forged in the west where the sun sets."