I'd love to do some world building for a kinky setting based on porn and kinks. I love treating sexual things as casual and wholesome, and exploring the logical results of these things for humor and interesting scenarios. I would like to include as many of the following elements as possible, these are not separate scenario ideas:
Drugs & Alcohol: This is a major kink of mine. I'd love a world where women all party hard, with suburban moms and office workers drinking, popping pills, and snorting coke like the most hedonistic students at a party school, and actual college students going even harder. Maybe overdoses and alcohol poisoning are even seen as no big deal, easily survivable by whatever means. All of this encouraged and approved of by society. Combined with the above, maybe even especially encouraged during pregnancy. This could also include cigarette smoking.
Incest: A world where sex between family members is totally normal, and a bonding experience. I'd especially like a lot of inbreeding. Maybe a lot of folks even disapprove of breeding outside the family.
Casual Sex: I don't like the dom/sub nature of freeuse, but the general idea that anyone could pair off, even strangers, and openly fuck in public is hot. Consent would still be there, it's just no one is likely to say no unless they're busy doing something else. This would also include incredibly slutty clothes being totally normal.
Extreme Proportions: Maybe women naturally have much larger tits and asses in this setting, or maybe they're induced artificially. Maybe they take fertility pills that cause them to grow extreme curves. If they're natural, maybe just as many or more opt for plastic surgery enhancements, or they're even considered necessary. Maybe a girl with tits smaller than her head is basically considered disabled, and will be given implants as a corrective measure.
Casual Breeding: Perhaps nobody bothers with condoms or birth control, or even pulling out. Girls just expect to spend most of their lives pregnant. They don't let it stop them from doing what they like. Sports, partying, casual sex, all done with huge baby bumps. Truly huge, since it'd be great if, naturally or intentionally, multiple births were the norm. Triplets being a small pregnancy, octuplets mundane, and for the high end, the sky's the limit.
Now, world building is fun, but I'd still like to have a plot. I think the best approach is probably to have one or both of our characters enter this world from outside. Maybe we're a family that moves to a new city or state that works like this. Maybe one or both of us wakes up in a parallel world like this. Maybe it's a series of genie wishes, or an app, or a magic rule book that transforms reality. It also might be more interesting if these changes happen over time, maybe a new political party changes the laws, or some organization is using propaganda to change people's attitudes about sex, or maybe we accidentally alter the timeline to be more like this, or the world slowly developes in this direction in the sci-fi future.
Kinks: Incest, (Hyper)Pregnancy, Huge Tits, Lips, And Asses, Public Indecency, Slutty Clothes, Trashy Behavior, Drugs & Alcohol, Smoking, I'm pretty open to other things that aren't my limits.
Limits: Gore, Poop, Anal, BDSM, Dom/Sub, needles, cumflation, cervix penetration.
Start with kinks and limits, and give me some idea of the kind of plot you want, or what our characters' relationship should be, or other ideas you'd want to include in the world building.