The Sime~Gen series of science fiction novels were written by Jacqueline Lichtenberg and/or Jean Lorrah. The series consists of eight novels and two short stories.
Humanity has split into two types, the Gens who produce selyn and Simes who must get selyn from Gens to survive. Gens look like pre-split humans, while Simes have tentacles growing out of their arms. If a Sime tries to suck selyn out of a Gen who doesn't resist and isn't afraid, both of them enjoy it immensely. If the Gen resists or is afraid, the Gen dies and the Sime is "junct", addicted to killing.
Naturally this leads to The End of the World as We Know It. To ensure that this is a total Crapsack World, one-third of the children of one type will be the other type. And there is no way to tell which you are until you "establish" or "changeover" as a teenager.
So if you live in Gen territory, you grow up knowing there is a one-third chance that you will turn into a monster and kill your friends and family, unless they beat you to death before you have finished changing. And your parents know this, too.
And if you live in Sime territory, you grow up knowing there is a one-third chance that one day all the adults will stop considering you a human being and instead think of you as a tasty, tasty treat. And your parents know this too.
Dysfunction Junction ensues.
Centuries later, Rimon Farris discovers that he is a "channel" who can take selyn from any Gen without hurting them, and give it to other Simes so they don't need to kill every month. Now the trick is to convince Simes that not killing isn't a sick perversion, and to convince Gens that Simes don't have to be evil killing machines. This first happens in communal "Householdings" in Sime territory, and eventually the whole world changes to the channeling system under the Tecton.
The books and short stories are:
- First Channel (1980) Reconstruction Era
- Channel's Destiny (1982) Reconstruction Era
- House of Zeor (1974) Householding Era
- Ambrov Keon (1986) Householding Era
- Zelerod's Doom (1986) Householding Era
- Unto Zeor, Forever (1978) Tecton Era
- Mahogany Trinrose (1981) Tecton Era
- "Operation High Time" (1969) Tecton Era
- Rensime (1984) Tecton Era
- "The Channel's Exemption" (1977) Space-faring Era
This series provides examples of:
- Achilles' Heel: Any Gen can kill the Sime first if they know where the Sime's conveniently at hand weak spots are.
- After the End
- All There in the Manual: There is a enormous amount of information in the fanzines and on the websites.
- Applied Phlebotinum: In the later books, selyn technology can do all sorts of great things, to the point of displacing most other technology.
- Artistic License Linguistics: All Simes speak the same language, Simelan, despite communities never having any contact with each other. Retconned as being a character's ignorant statement.
- Being Evil Sucks: Juncts usually are sick and die young.
- Crapsack World
- Dark and Troubled Past: Almost everybody, given that 1/3 of all teenagers are murdered.
- Dysfunction Junction: Given the situation, no one has much of a chance of being emotionally healthy and not living their whole life in denial. Members of Householdings are the exception. Maybe.
- Evil Feels Good
- Evil Is Easy
- Evil Tastes Good
- Fan Fic: Lots of it, some of it officially recognized by the original authors.
- Fantastic Racism: Lots and lots, naturally. Early in the chronology, Simes view Gens as livestock, and Gens view Simes as soul-sucking demons. It gets better eventually.
- Forgets to Eat: One reason junct Simes are usually unhealthy -they don't eat enough to support tissue repair and their organs eventually fail. Simes who live peacefully with Gens have less of a problem with this because the appetite of hungry Gens can induce Simes to eat properly.
- Good Feels Good: But is much harder to achieve.
- Heroic Willpower: The Tecton tries very hard to train people in this. Sometimes it works.
- Hidden Elf Village: The Rathorites are a secret society/hidden community who have tools that could go a long way towards fixing the problems of the world, but won't reveal them because they could be misused.
- Lean and Mean: While even healthy non-junct Simes are thin on average compared to Gens, junct Simes tend to be even thinner due to their above mentioned tendency to forget to eat. carried to extreme by the Freeband Raiders, Simes who exist outside "civilized" junct Sime society and kill more then they need to for the sheer pleasure of it. They are described as "skeletal". They also rarely last more then 5 years in that lifestyle due to generally eating nothing at all and excessive use of augmentation.
- Life Energy: Selyn
- Liquid Assets: Selyn
- Lost Technology: The Ancients were able to do all sorts of cool stuff.
- Magic Feather: The Starred Cross, a symbol that will protect you from Simes if you believe in it. Justified because Simes can sense your fear.
- Mundane MacGuffin Person: In the first novel, House of Zeor, she had to introduce complex biology and historical-political background. To support the worldbuilding, rather than pile a complicated plot on top of a complicated SF premise, she uses a simple MacGuffin plot: The Gen protagonist Hugh's girlfriend is kidnapped by Simes because she works for the Gen government in the department that prints money. (they want to flood the Gen economy with forged currency). We don't even meet her until the climax of the story, and she clearly serves only as devices to force Hugh to infiltrate Sime Territory. The real core of the novel is Hugh's developing relationship with Klyd, the Sime who helps with his mission.
- Obstructive Bureaucrat: The Tecton ends up being run by these.
- Our Vampires Are Different
- Parental Abandonment: Simes tend to die young, leaving their children to become orphans. If you are lucky, one of you will get a Promotion to Parent.
- People Farms : The Gen Farms in Sime Territory (pre-Unity) where Gens are confined for sale to Simes for killing. Children born there are raised like livestock, and the few who change over into Simes at puberty instead of establishing as Gens are released into society, but their prospects aren't good.
- Psychic Powers: Simes can "zlin" which lets them sense emotions and gives them a kind of X-Ray Vision.
- Run for the Border: Anyone who changes into the wrong type for their territory has to do this. Fortunately there are Shrines of the Starred Cross as an underground railroad for Gens.
- Sensory Tentacles: The Simes were a mutated branch of humanity that could sense life energy (and often other things) via two pairs of retractable tentacles on their forearms.
- Single-Target Sexuality: Can happen to channels sometimes. Can be cured the obvious way.
- Super Strength: Simes get this and Super Speed by spending extra selyn, a process known as augmentating.
- Unspecified Apocalypse: The fall of "our" civilization was caused by the mutation that split humanity into the titular Simes and Gens, but what caused the mutation to occur in the first place has no definitive explanation and, according to the authors, will never have a definitive canon explanation, though in character speculation is fair game.