Suddenly I wonder, can one define an infinite series of Omelas-type societies along these lines: Omelas represents the case n = 1 where n is the number of children who must be kept in permanent suffering in order to maintain social stability. We could perhaps rename the n = 1 case the "Monomelas" scenario. Then n = 2 is the "Bimelas" case, n = 3 is the "Trimelas" case, and so on.
There's a hypothetical "Nomelas" where n = 0, but its existence is doubted. There's even the possibility of n < 0, which would suggest that one or more children must be kept in permanent bliss in order to sustain society, but let's not get carried away here.
~Chara
"In order to keep our society functioning, one child must be maintained in a condition of absolute freedom and joy. Given everything they want for no cost, whenever they want it. Yes, it's an expensive trade-off for our city to make, but it's the only way for Antimelas to thrive as it does."
"So how does it work? Sympathetic magic?"
"No, no, don't be ridiculous, magic isn't real. But the child may, for instance, walk into the city center and say that seeing crumbling buildings and hungry people makes them sad, and we will be obligated to repair the buildings and feed the people in order to preserve the child's happiness."
"Isn't that just a king?"
"No, because they're not allowed to make trade-offs of their own. If they ordered us to go to war, saying that they did not want to make this decision but felt it was a grim necessity, they would have no such authority. The child may only request things that make them happy."
"What if the child became cruel, and genuinely was made happy by the suffering of others? Or callous, and would be equally happy whether the hungry people were fed or simply shuffled out of sight?"
"This is surprisingly rare! Few people can directly admit to wanting such things, when denied the ability to claim it as a reluctant sacrifice. But, if a child were to make a request like that..." and here the mayor of Antimelas looked the traveler right in the eyes before continuing, "It doesn't always have to be the same child."