Lycanthropy itself, the disease which causes and enables transformation from human to beast form is little understood, similar to the creation of vampires. Most theories center around some sort of magical contamination causing cellular level changes within the afflicted's body allowing at will transformation to a pre-determined beast form but, yet, ironically, blocking all usage of magic in the process. There are also theories that long ago vampires created the Lycan as a sort of cattle to be used as a food source with a higher pain threshold and ability to survive extreme blood loss. While there are apocryphal stories supporting of this happening the wide diversity and spread of the disease to far flung corners of the planet don't support this theory.

 There are many different kinds of shapeshifters: bears, wolves, foxes, even snakes. Unlike the transformation of a demihuman,  the process for a lycan is an agonizing one and can leave all but the most determined and hardy Lycan writhing in agony for minutes once complete due to the physiological changes taking place during the transformation. However, even with their ferocity Lycan are generally more intelligent than demihumans and retain more of their human qualities once transformed with greater control over their tactics and abilities and reasoning they can fight with purpose and determination rather than rely largely on instinct like most demihumans.

The Lycan society is largely pack based with the alpha being in charge and the others following the hierarchal rules. Leadership of the pack and often is contested by combat with the winner taking over or maintaining their position while the loser is exiled. Since the disease prevents the use of magic Lycan society is dependent on physical ability rather than leaning one way or the other with gender.

Lycan were treated as slaves by vampire society for hundreds of years and the two have groups have an innate hatred of each other based on their shared history.