Dude, no demon or angel is a “good guy.”
Both the New Agers with angels, and the demonolators with demons, like to proclaim that neither will ever hurt you but every spirit has an agenda, and they will fuck you up if it fits that agenda. There are plenty of people, some even on this forum, who have had their lives destroyed by the most popular demons, and others who have been stalked and harassed by angels.
You have to understand that the very demons you call on to strike down your enemies, or to dominate the will of your boss, are fully capable of doing the same thing to you if they want to.
Demons are not fluffy pink bunnies and it is silly to think they are.