Onbaru was a large demon who's entire body was covered in a thick black shell like armour. He had a large sharp toothed mouth and a large crest on his head. He had two bird-like heads on his waist and a large pair of somewhat out of place bird wings on his back.
Onbaru is only shown in flight. His large claws are would of likely caused some pain as well.
Onbaru was among the demons that came together to fight against God and his Angels after he planned to wipe them out. He could be seen approaching a group of Angels alongside Wellbuth and Calgery. If he died in the battle or went into hibernation like many other of his kind is unknown.