Familiars are the spirits that attend on witches, magician and sorcerers. Some believe that familiars are found in the rings, lockets and trinkets of the magicians, witches and sorcerers. Cornelius Agrippa's black dog is one of the most famous familiars, as it was claimed that the dog was the devil in disguise - and that he accompanied Cornelius wherever he went.
It is possible for a familiar to choose and attach itself to a master without any calling or invocation, although they can only be banished through exorcism. Paracelsus was said to have a familiar that he carried in the form of a sword, and it was claimed by Naude that he never let his sword out of his sight even to sleep. He would strike it to the floor before going to bed when he needed money, and there would be a bag of gold in the same spot the next morning.