The Herd is a modern fantasy setting with magic as well as technology. The world is a much brighter place than the world of today and is comprised of Anthro animals and Sapient 'Ferals'. Humans also exist in this world in a fairly equal amount. Terran civilization is on the brink of interstellar travel but it's gaze is still quite set on bettering Earth before taking to the stars.
Pieces in this setting focus on a farm located somewhere in midwest USA where a Brood Dragon called Yarrow makes her home. Her species is one that does not reproduce sexually, instead she transforms willing sapient creatures into beings like her. Visually she resembles a cow / dragon hybrid. Her magic is based on desire and will, she cannot permanently transform anyone in a way they do not desire. (She wouldn't want to, either, she's very kind!)
The life of those she transforms are those of unrelenting pleasure and belonging. They pay for their lifestyle by selling magical transformative tonics derived from their "animal" products (Eggs, Milk, Cum). Similarly, they run outreach programs to recruit new members to the herd. Yarrow is the leader of this herd and the only one capable of creating permanent members, all other goods produced offer only temporary transformative properties. This is typical for her species. Her magic is derived from fulfilled desires, without her 'hoard' (Her herd is her hoard!) her power would be minimal.
There are...theoretically, other Brood Dragons with differing themes.