“The only way to determine if you are being vampirized is to weigh what you give the person compared to what they give you in return. You may, at times, become annoyed with the obligations put upon you by a loved one, a close friend, or even an employer. But before you label them psychic vampires, you must ask yourself, "What am I getting in return?" If your spouse or lover insists that you call them frequently, but you also require them to account to you for their time spent away from you, you must realize this is a give and take situation. Or, if a friend is in the habit of calling upon you for help at inopportune moments, but you similarly depend upon them to give your immediate needs priority, you must regard it as a fair exchange. If your employer asks you to do a little more than is normally expected of you in your particular position, but will overlook occasional tardiness or will give you time off when you need it, you certainly have no cause for complaint and need not feel he is taking advantage of you.”

The Satanic Bible (1969)