A putrid green glow shone from deep within Erra's pitch black lenses. Lucifer's capital was a billowing mass of nightmarish spires and vast gothic castle-complexes hewn from jagged obsidian, the pulsating flesh of sinners, crystalline souls, and other esoteric materials she had yet to identify. Agonized screams coming from Famine's brothel oubliettes carried even to the industrial plague district. Erra found the chorus both a lyrical and haunting performance, and she envied Limos and Jiha's dominatrices and dominants their sublime understanding about the depths of pleasurable suffering.
Her father's citadel on its own rivaled cities in size, not counting the laboratories, dungeons, and so much more that formed a vast underground and labyrinthine fastness. A sickly haze lay thick on the district's ground level, shrouding many of the demons and humans working in her father's contaminant-spewing factories as they carried out their work to forge Hell's blighted weaponry. Spontaneous mutations were common, as were deliberate experiments to turn the inhabitants into abominations and amalgamations of flesh. Stabilized strains existed within the army and workforce, but the district was a hub of continuous innovation. Together, the rival Plague Guilds contributed much to Lucifer's infernal domain.
Her platform-heeled feet clicked against the floor as she turned from the awe-inspiring sights of the balcony to her personal atelier's main hall. A mottled reddish texture had permanently seeped into the stone in misshapen smudges, concentrated around the drains. Everything existed in a seemingly chaotic mess, with arcane and alchemical devices and tools sitting beside futuristic machinery. Only the bookshelves and her operating theaters possessed a measure of clinical order – her father's daughter, in other words.
Between herself and the other Horsemens' corrupted spawn, the latex demoness suspected she had changed the least mentally. Galib had only released her inquisitive and utterly depraved and evil mind from its mortal shackles. When seeing her mother and father howling with lust as they transformed into little more than sex-toys, the bespectacled Iris had pleasured herself while eagerly taking mental notes and observations. Even if her jovial attitude disturbed some test subjects, the casual conversation as she described their transformations amongst other things, Erra saw no reason to change. Almost all saw things from her perspective, eventually. Or their minds broke into a gibbering mess.
Her rubber form creaked as the hoses on her back extended, curling in the air like tentacles before attaching themselves to a nest of tubes hanging from the ceiling. After a few seconds, a glowing green liquid began coursing through her tubes before it spilled into her growing, hollow breasts. Poisonous emissions exuded from the pores of her mouth-filter, surrounding her in a faint and shimmering mist. She could create toxins naturally, but this level of potency... a metallic moan echoed against the walls as Erra nearly doubled over... and ecstasy could only be reached through artificial means. The rest of her body followed her massive mammaries, the latex husk swelling into that of a voluptuous and nightmarish seductress in order to contain the mutagenic gases and toxins within her.
The rubber woman disconnected from the tubes, which spilled their remaining contents onto the floor in a single deluge, before limberly stretching like a lazy feline. This was absolute bliss.
Only Menhit had similarly exotic and alien anatomy. Perhaps that was why the two ladies-in-waiting had struck up such a friendship, Erra becoming Menhit's confidant as she courted their princess before she was even aware of it. Of Princess Deonna's friends, she was closest to Lady Malice. Whereas the necromancer dealt with the dead and souls, she experimented with life and flesh. While Erra couldn't smile, her face a near featureless gasmask, the emerald light in her eyes twinkled. Such a wicked mind the goth had.
Then there was the nobility of Hell; from the dukes and duchesses ruling one of Hell's layers to the lesser nobility. As the demoness sorted through her research notes inscribed on dried skin, she felt glad that the Horsemen stood apart from that hierarchy. Mostly she had to deal with the Meisters of the Plague Guilds, but their insights on her research and how to best keep her test subjects healthy were welcome.
"Our cages are nearly empty, mistress." A woman's voice hissed behind Erra. The latex demoness turned, briefly inspecting her research assistant and former test subject carrying a clipboard and doctor's coat with a hungry gaze. Rows of leaking breasts adorned Zhang's chest which emerged from a double-headed penis tail like the stem of a flower, one of the urethra stretching around her feminine crotch as the other is used to slither across the atelier's floor. Her slender and serpentine neck ended in another noduled cock, the slit replaced with a pair of full lips. Zhang seemed to blush slightly under the scrutiny and tried to tuck her head away. So little remained of the former human who had resisted all of this. The act of transforming her had been almost more of a turn on than the erotic and insatiable monster that emerged from the vat.
Stone gargoyles left their perches to clean up the trail of effluence the lamia left. With their inanimate skin protecting against any stray biological agent from affecting them, she preferred them over imps and other lesser demons. They also struck quite imposing figures while they rested.
"Nothing to it except gathering more test subjects." Erra's voice chimed happily with a static crackle. "Hmm, was a while since I visited the slave markets. Those poor souls could do far worse than be used in my experiments, like ending up as fodder for Anat's coliseums. Although capturing a few of the humans and their angel allies still on Earth would the real prize." She made a dismissive flick of her wrist before collecting the last few sheets in a neat stack. "But we all need to occasional break from work, and now seems as good time as any."