To understand the existence of werewolves, or Garou as they call themselves, one must first understand how living creatures work. All things, whether living or inanimate, are made up of certain Patterns and sustained by the flow of energy, or quintessence, running through them. The interaction of the pattern and the type of energy flowing through things determine what that item is. Animals and human beings have different patterns and a different type of energy flowing through them. This is what makes animals and humans different. Werewolves possess an innate ability to alter their patterns and the type of energy flowing through them. By changing these, they are able to alter their forms. In their human form, they have a human pattern and human energy flowing through them. IN wolf form, they have an animal pattern and animal energy flowing through them. They also have an in-between form. I believe they refer to this as a Crinos form. In this form, they still have a human pattern, but they have animal energy flowing through them.