Bi m/f couple who finally decide to pull the trigger and have that mmf threesome they've been talking about. (Un)fortunately for them, their mysterious third ends up being supernaturally virile and seductive. What started out as an introductory and experimental session ends with both of them comatose and nursing cum bellies, her womb and his colon completely stuffed full of his concrete-thick seed with their benefactor disappearing into the night. As the weeks go by, both of them start to exhibit pregnancy symptoms, though both of them chalk his up to couvade syndrome. Nauseous, sore, and more than a little insecure about how his girlfriend is likely carrying the strangers baby, his and her world is turned upside down when an ultrasound reveals he's growing their breeders baby inside his guts too. Their pregnancies progress, hers is perfect as she enjoys every second of it, the baby kicks cutely as if on cue, and she glows and feels fantastic while his, due to its supernatural nature, is miserable and embarrassing. Remodeling organs that weren't meant for reproduction into such means his guts loudly protest their state, gurgling and bubbling loudly as they stretch to accommodate both the growth of his unnatural womb and the painful constant thrashing of the spawn fighting for space inside him. Angry red stretchmarks on his sloshing lopsided torpedo belly, contrast with her flawlessly smooth spherical bump. They support and find each other irresistible in their states, the girlfriend especially supportive as she guides him through his changing body as his hips painfully widen and pecs bloat into prematurely milking udders. As they both go overdue, with no induction techniques working, they realize the cock that put them in this state is the only way to get them out of it
π Oh, this is a beautiful scenario~ Partners pregnant together, thanks to a mysterious inhuman third - with internal remodeling to boot! And it's arduous and noisy, as it should be~ But what a sweet twist, that hers is easy unlike her hubby's π She's such a good girl for taking care of her growing man, while she herself is pregnant~ By the end, I imagine he looks every bit as maternal as his girlfriend, albeit far more wretched looking -- but she too would get uncomfortable before long, as their pregnancies continue along without their breeder's intervention... who might even be counting on it, watching from the shadows as they blow up further and further, increasingly dependant on each other and desperate~~