Sometime in the not to distant future...
Humanity had many common myths throughout its history, two of which where aliens and werewolves. But what no one realized was that they where one in the same.
It began one ordinary day quite innocently, across the planet a strange mist fell that seemed to permeate everything. Most people didn't pay it much notice until the following night, across the world 50% of the human males where transformed into hulking wolf like creatures. Not too long after, Earth was visited by an alien race calling themselves the Lycothans.
The Lycothans had long ago marked Earth for colonization, and had been waiting for humans to reach the right level of technological advancement. They came in two forms that most of them could alternate between, one resembling a feral human, the other a humanoid wolf creature. They quickly overwhelmed the military forces of Earth, and set themselves up as its new rulers. Quickly the humans learned what this would mean, the Lycothans had long ago figured out how to transform other races into their own, which was to be the fate of Humanity.
Its only a few months after the invasion began, humans are dwindling, resistance attempts are put down quickly, and it seems that the Lycothans are going to win.
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Okay, the Lycothan transformation itself is both physical and mental, even in the feral humanoid form they have canine traits like enhanced senses and physical attributes and anatomy. In addition, when transformed they are changed mentally to believe that they have always been Lycothan, giving absolute loyalty to the pack, but this doesn't always work out.
While the transformation can be enacted through biting, Lycothans take little pleasure in this act, and prefer to do it through sexual intercourse.
The Lycothans are broken up into several castes, any transformed humans can be made into a member of a caste, other than the Thrall caste:
Alphas: The leadership caste, members of this caste run the government and are marked with a golden streak in their fur, considered the most beautiful and elegent of the Lycothans, they are highly intelligent and cunning. Only the most important of other species are brought into this caste. Also Lycothans are matriarchal, while this caste can be either gender, the female gender is more important.
Warriors: The Soldier caste of the Lycothans, the Soldiers are usually marked with a silver streak and can be either male or female, this caste is what fights for the Lycothans. The Soldiers range from little more than dumb grunts to highly calculating warriors and generals.
Servants: This caste lives to serve the upper two castes, marked by a white streak in their fur, they can be male or female and only exist to serve their master's every whim.
Thralls: This is a male only caste, this caste is what half the human male population was turned into prior to the invasion. They are mindless animals who can only act when given orders by a more powerful Lycothan.