>Shameless Equestria, where the concept of shame doesn't exist because shame is a human thing (adam and eve bullshit) 
>and everypony is naked anyways with their genitals just out there 
>and that even Rarity, despite being a seamstress, hardly wears full clothing either 
>and since Equestria is a utopia with zero shame, a booming economy, and safe pony communities, population rates skyrocket because high happiness = population growth 
>which basically means ponies talk about sex casually and fuck often
>And the final twist: this is Molestia's Equestria, where something broke inside of her after banishing Nightmare Moon
>Luna was supposed to be Celestia's one constant in life in their shared eternity together, but Celestia was forced to banish her
>This left a growing hole in her as she forms bonds that are doomed to fade over the next 1000 years, leading to her descent
>She then decides to engineer the biggest hedonistic empire to cope and drown out the grief with endless pleasure
>Population booms to fill the void, and a society where connections are shallow but constant, with no room for pain or loss.
>Equestria becomes a shameless utopia where Discord finds himself out-freaked by Fluttershy's bestiality fetish
>where Tirek is drowning in mares that want to be dominated, and so he becomes a Canterlot nobel when every mare throws their bits (both coins and genetalia) at him
>where Chrysalis' empire is based on sex fulfillment courtesans that ponies pay bits for, with Changelings being able to shapeshift into any fantasy a pony wants
>and where Cozy Glow is too busy enjoying stepping on stallions to be an empress. Cozy Glow above all wants a sense of control and for nopony to leave her, ever. So her being a pint-sized dominatrix makes sense, which would curtail her motivations for ruling Equestria.
>And Luna returns completely mortified to see what Celestia's empire has come to, as she's the only sane pony with a sense of shame left. She's been gone for 1000 years before Celestia's hedonistic era, so Luna would naturally be the only pony that can see the contrast to modern pony's shamelessness compared to pre-unification ponies. She is mostly horrified at the at the loss of emotional depth/intimacy that these shallow hedonistic relationships creates.

>The Element of Harmony bearers also share similar corruption
>Pinkie Pie celebrates orgy parties where magical contraception spells are widespread and common, spreading laughter and happiness
>Rarity is generous and builds her clothing empire on selling lingerie and discovering unicorn horn sex as an exploration of unicorn couple intimacy
>Applejack is just honest about needing a good rut so she can clear her head and get work done on the farm. Family reunions are also orgies since contraception spells exists and even if they do have foals, magical gene editing is advanced enough to avoid any birth defects or problems down the line. AJ's family values center on togetherness, dependability, tradition, and openness. In a shameless world, "togetherness" extends naturally to bodies. Why stop at shared labor or meals if physical relief strengthens the family bond, clears heads for better work, and keeps tempers even? She'd see hiding desires as dishonest, pretending boundaries exist where magic proves they don't.
>Rainbow Dash's brain being wired for peripheral vision forces her watch so many ponies having sex, which causes her to be a natural voyeur. She's still loyal to ponies, especially to those she has casual sexual relations with,
>Fluttershy is funded by Canterlot's scientists to fuck animals since it helps them study cross pony-animal diseases and to help animals better. Her being a bestiality freak also makes her primed to bag Discord since she's more freaky than him and likes his mismatched animal parts.
>Twilight is literally also the personal student of Celestia, so there's no chance she wouldn't be corrupted too. Her trait to obsess over things can be guided by Celestia for her to focus on community happiness and population growth, to have her believe her teacher's hedonistic utopia is the ultimate culmination of harmony.
>Celestia commanded Twilight to use the Elements of Harmony on Nightmare Moon to restore Luna instead of corrupting her, because she still wanted her real sister back.
>the wound is real, and Celestia fears losing Luna if she ends up corrupting her as well
>It's also the only time the Elements of Harmony were used, as it was shelved afterwards due to the other threats not needing it to resolve them.

>Cadance, the Princess of Love, is naturally corrupted by the shameless lust ponies have and Celestia's teachings. Love is now redefined as maximum public orgasms and population growth.
>Shining Armor supported Twilight’s tutelage under Celestia and became the official orgy coordinator
>Crystal Empire returns, Crystal Ponies wake up blinking and confused, and Celestia sends both Cadance and Shining to "help" them.
>They are immediately hit with Cadance's pink lust aura that makes every touch feel like a full-body climax.
>Shining re-trains the Crystal Guard into "Pleasure Cohorts" doing synchronized breeding drills in the streets.
>Every plaza, hallway, and balcony becomes 24/7 open-air fuckfest
>Magical contraception and gene-editing spells handed out like candy
>Crystal Heart starts pulsing pure horny energy instead of old harmony crap
>Ponies go from "what the fuck happened" to "fuck yes breed me in public" in under a week
>Then King Sombra teleports in for classic evil conquest
>gets absolutely swarmed by hundreds of crystal mares and stallions begging him to dominate them
>Cadance blasts him with concentrated corrupted love magic from the lust corrupted Crystal Heart
>Sombra's rage boner turns into actual boner and is corrupted as well
>He rebrands as Prince Sombra, Lord of Dark Delights
>now runs royal crystal dungeons where nobles and tourists pay premium bits to get collared, spanked, and utterly used by him
>keeps the smoky mane, red horn, and edgy armor because it makes the mares cum harder
>tourism from Canterlot and Ponyville skyrockets and the Crystal Empire becomes the glittering crown jewel of the shameless utopia
>all according to Celestia's keikaku

>Of course this hedonistic empire isn't perfect, as overpopulation is a real concern as exponential growth makes the looming crisis inevitable and countries outside of Equestria (like Griffonstone) would become baffled by their shamelessness, making negotiations harder to succeed in.