Hierarchy of Angels and Demons by ~justdejan on deviantART.....until the second coming of Christ the battle will rage on. Pinning this for later, I don't think I have been introduced to all of them yet, only just finished s5.
The legends go that the first incubus was born of a demon and angel. Abandoned by both parents on earth, he became jealous and searched for a way to increase his power so as to destroy them. He found that through sex he was able to absorb the life force of a human.
And even those who were once your friends may soon fade away--or worse, stab you in the back with cruelty--because it's easier for them to force you away than to have to face you and feel "uncomfortable" because of what you went through.