The Animus are humans who have been changed to have more bestial attributes, sometimes mimicking werewolves of legend, or another demi-human demi-animal of myth.
Common traits are copious amounts of hair(fur), claws, predatory teeth, increased speed or strength. Rarer traits have been seen, such as gills, tusks, sharkskin or hooves.
Due to their largely unrelated natures, most animus are solitary or form packs/herds with people who share similar attributes. Another effect of the large differences is a social stigma that most normal humans think them stupid and bestial, this has lead many animus to resent their parentage.