For example, consider Daniel 10:12-13 wherein the angel speaking to Daniel had to fight with an evil angelic being called the Prince of Persia and needed the Archangel Michael to help him.
Sorry that I was unclear. Jude 6’s reference is usually thought to be to the fallen angels who left their boundaries and impregnated humans. As interim punishment God has kept them bound in the dark abyss, which the demons of Luke 8:31 greatly fear. All other demons roam freely.