Her new body was magnificent... and yet she could see the value in simplicity. This was a thought that she expressed in quiet whispers to her clone-lover, in between soft, tender kisses. "For now... let's lose the extra pairs of things..." She grinned. "But... the enhancements... those can stay..."
Catherine raised one eyebrow slightly. "Mmmm. Minimalism perfected.... I can do that." She held one last long, passionate kiss with her doppelganger before standing up, a hand gingerly holding Allison's as she stared into what was effectively her reflection with the most lovesick eyes imaginable. Allison's heart fluttered under her twin's gaze, and continued to skip beats as the brilliant trillionare led her over to another locker, pulling out several vials and creating a mixture of them which she was soon injecting into first Allison, then herself.
The burn of the retrovirus was, at this point, a source of pleasure as much as one of pain. She grasped Catherine's arms in her own as both women began to scream with agonized delight, their bodies pressing together as flesh melted back, arms and legs and breasts receding. The balance she had attained was thrown off as her extra limbs and second rack retreated into her body, leaving her once more in a conventionally bipedal shape. And yet she retained the enormity of her enlarged chest, the raw power of her enhanced muscles, and the throbbing, aching pleasure of the member that still accompanied her folds.
They were much closer to human, certainly - both women now appeared to be the finest specimens one could hope for that were still something inarguably humanoid. She panted heavily as she looked up into Catherine's eyes, the pain of the change having brought on a new flame of desire that begged to be quenched. In spite of their mutual exhaustion, they once again dove into sloppy kisses, bodies rubbing against each other and rods stiffening. It was almost trivial now, guiding their long shafts into each other's openings, crying out in mutual glee as they pumped new, fresh loads into each other.
Just as familiar, too, was the sensation of their sticky white fluids affecting each other. It hadn't occurred to Allison or even to Catherine that, after the injection, contact with each other's cum could once again trigger mutations - and as said alterations to their genomes took shape, neither woman cared. In that moment, they lived for nothing more than each other, for one another's company, to be close as they altered each other's bodies with wild and unpredictable results. It was a heaven that hurt like hell, and Allison couldn't imagine anything sweeter.
With how unstable their bodies already were at this point, perhaps it was no surprise when a reaction completely unlike what they'd experienced before took place. Allison sharply cried out as she felt skin tightening up and latching onto her giant stick, followed promptly by a similiar occurrence with her own soaking wet folds sealing around her lover's rod. Their massive, heaving breasts, already squished together tight, became positively stuck - and they both again screeched as the skin and nerves melted into each other, their nervous systems uniting.
"What's... what's happening..." Allison asked quietly, though she desperately wanted it to keep going. Catherine, for her part, didn't respond, instead fumbling for another needle which she quickly injected into herself. Allison could feel the prick as if it was penetrating her own body - because it was. They were no longer seperate organisms. They were one being, flesh and bone squeezing together, melting into each other, and Catherine's injection only heightened every sensation tearing Allison's mind apart.
Before, they had been fusing slowly - now Allison was practically being dragged into Catherine, as if some invisible force was drawing her in closer, forcing her very essence to seep into her lover. Their whole bodies from the neck down were a mess of flesh in a vague humanoid shape, until finally, their faces began to melt together. The world went dark for Allison, no sensation or feeling other than the ecstacy of her body being pulled and twisted around for quite some time. Sight only returned after what felt like years of pure bliss, slowly, but... odd. As if... as if two sets of eyes were feeding into her brain.
Staggering to a mirror, she was able to quickly deduce why that was - or rather, they were. Allison and Catherine's identical heads sat atop the torso of a body that took their breaths away. Easily eight feet tall, the muscles of every arm and leg on display, bnorderline amazonian in build - but even amazons lacked eight gigantic breasts, or eight powerful arms, or eight long, lissome, perfectly smooth legs. Even the mightest of mythical warriors lacked such wonders as the pair of vaginas and penises, with four matching testicles, that dangled from their groin... and from the back of their octopedal lower half, a whole other set of double genetalia. All four members were stiff, all four holes were soaking and begging for penetration.
"Our bodies were less stable than I realized," Catherine mused, controlling a pair of arms to heft one of the matching rows of enormous tits. "But this form is..."
"Godlike," Allison finished. Her whole nervous system now intertwined with Catherine's, their minds were more or less one split into two brains. Catherine now well and truly was in love with herself - and Allison loved herself back. Their eyes glistened as they gazed at each other, shared arousal lighting fires all over the incredible form they now shared. A thought occurred to Catherine, and Allison instantly knew it, and silntly agreed. The sheer blessed joy of this state of existence - it had to be shared. It had to be given to everyone. Every human being alive needed to become Catherine, to unify with them into a single organism of bliss. And what better place to start than with the tittypede still writing around behind them, staring up in bedroom-eyed wonder at what had become of her employer?