Out in the distant reaches of space, beyond the constellation of Orion, lies the swamp planet of Acadia. Humanity has yet to set foot upon its hot and humid surface. As far as the most learned Leech knows, there is no other life than that which wriggles its way upon their own world.
On Acadia, the Leech were the first life form to achieve sentience. As time passed and Leech hunting techniques matured into raising and herding animals, the Leech grew in size until the average lay at more than 8 feet in length. Huge, fat, green leeches with two proto-tentacles each, the building of tools was beyond their physical capabilities.
This problem was solved by the slow appearance of psychic abilities in the Leech. The Leech developed a limited form of projected telepathy allowing communication between themselves. This is their only form of communication, as they can vocalize no more than simple grunts and screeches. Each generation, their powers grew until telepathy became mind control, which allowed them to exert their will upon the lesser beasts.
The small, chimp-like Humes appeared to be the easiest to control with these powers and quickly became slaves to the Leech. Indeed, a Leech Lord’s wealth can be measured by both the size of his herd and the number of slaves held in thrall.
The greatest of the Leech meet often to debate philosophy. The largest and the fattest are considered among the most wise and hold a greater “weight” in all discussions. The richest Leech often provides the meal for those gathered, generally one of the large, floating swamp cows (similar in appearance to a manatee) which will comfortably feed a dozen Leech Lords simultaneously.
A few Leech work as scribes, writing down the wisdom and historical facts spouted by the great philosophers. Such work is not fit for the minds of the Humes. Special waterproof inks on treated skins are used. It takes a great deal of training for a scribe to learn to use his proto-tentacles to handle the writing implements.
The majority of the Leech workforce are made up of foremen who manage the Hume thralls on the orders of their betters. A Leech foremen is judged by the nature of his field. Managing herders or house thralls is considered a weak job, while directing the work of craftsmen is more socially acceptable.
Leech wives are properly kept out of such manly things as philosophy, literature, and managing Humes. The wives of Lords tend to congregate during the day and share poetry, none of which is ever recorded, as that would imply the silly notion that women have thoughts worth paying attention to. The wives of scribes and foremen do tend to manage the house thralls themselves, as they are not rich enough to employee their own foremen.
At less than 5 feet in height standing fully erect, a typical Hume is quite diminutive in size. They have typical simian features and are covered in a fine, silky hair. More like lichen in appearance, this hair ranges from brown to dark green in color, which allows them to blend in with the foliage of the swamps.
Hume intelligence has grown throughout their subjugation to the Leech. They have begun viewing the Leech as gods, even going so far as to sacrifice the sick and elderly to them as a way to paradise in the next life.
Humes breed quickly and are highly social amongst themselves. A few of the Leech have begun to fear a world where the Humes become resistant to the age-old mind control or if their intelligence rises high enough to fully grasp the situation they are in. These Leech are considered nothing more than alarmists by the majority. The Humes have been under Leech control throughout all of known history; the idea of the world sprouting wings and flying into the heavens has more likelihood in the eyes of the average Leech.
A spacecraft full of explorers has discovered Acadia. They first encounter the numerous Humes and start hearing about their benevolent gods. Chalking it up to superstition at first, they soon learn the truth when they observe the ritual sacrifice of a Hume too old to work.
How will they react to the Leech? Do they attempt to rescue the Humes? Would the Humes go along with it or would they seek to protect their sacred gods? To further complicate matters, the Leech have an extensive knowledge of herbal medicines that could be of benefit, enough to be worth trading for. And Leech find human blood especially tasty.
Adapting to Fantasy
With the lack of modern or futuristic technology, the Leech could easily be adapted to fantasy. Perhaps man is venturing deeper into the jungles and the swamps than in previous times, when they stumble upon the Humes and the Leech. The sci-fi plot hooks would fit just as well in such an instance.