Mary's stomach more than rumbled, it roared. Her lungs more than heaved, they rebelled. She could feel Sencia moving inside of her body, feel her chubby flesh and the organs within being consumed and replaced. Her breath caught in her throat and gurgled as the expanding new forms of Sencia overtook her lungs, replacing them from within. She gasped, coughing and sputtering a thick slime that leaked from the corner of her mouth. Through her bond with Sencia she felt the symbiotes fear being replaced by a pure ecstatic joy, and despite the tremor of fear Mary felt she couldn't help but feel the quiver of excitement that she shared, feel the pulsing from between her thick thighs.
"If..." Mary gasped, her voice thick with a gurgle added by the slime filling whatever was replacing her lungs, "...I'm going out...I'm going out on my terms." She stood, pushing off the back of the couch, thighs quivering as she stumbled from the living room to her bed room. As she walked she passed by a floor length mirror, and from the corner of her eye she could see the way her soft heavy belly seemed to be squirming and distorting with internal movement. Panting and coughing up more slime, she dropped heavily onto her bed, the box spring groaning heavily beneath her. Her left hand scrambled as she felt a throbbing cold sensation in the center of her chest, could feel Sencia spreading through her veins and replacing them with something else. She lifted a hand and watched as the faint blue veins visible there started to darken, growing black and swelling, bulging beneath her skin.
Sencia throbbed inside Mary's body, having by now consumed her stomach, lungs, and womb. Eagerness flooded Mary, telepathically broadcast to her by the symbiote as it continued to consume and replace more of her organs, improving her according to some plan or idea that Mary was not yet aware of. She could feel the drooling escape of arousal from between her thighs and with a black-veined hand she reached out blindly, grabbing the cool white plastic handle of her vibrator. The soft rubber bulb at the tip began to quiver as she turned it on, the whine of the motor filling her bedroom before it was drowned out by her moans and a wet slurping noise as she placed it against her clitoris. She arched her back, head turning towards the side, catching a glimpse of herself in the full length-mirror on the wall.
Even in the poorly lit room she could make out the changes as they continued to spread, reaching further outward from her devoured organs. Mary gasped and writhed, pressing her hips down towards the throbbing head of her vibrator, seeing as the room started to be lit by a new source of life. Leaking from the symbiote that had replaced her devoured womb, from a needy pussy that was starting to change before her eyes, Mary could see the brightly glowing and bioluminescent fluid leaking from her body. Shuddering and shifting her hips, lifting them higher she could see the pale blue color spreading over her fat thighs. The vibrator partially obscured the bush of her sex, the thick lips turning from pink to a glistening onyx now drooling glowing neon blue lubricant. The black labia grew longer, and strange, lacy and seeming to wriggle with a life of their own, grasping at the throbbing head of the vibrator as it mashed against a clitoris that was growing larger, tapering now to a point, a brilliant cobalt blue among a sea of black folds the size of Mary's thumb.
The pale blue continued to spread across skin, pushing out hair follicles as it went, replacing human skin with a rubbery texture utterly hairless, pubes now drifting and sliding off of Mary's body and onto the sheets as she continued to hump and writhe against her wand. She shuddered, toes curling and realizing they had grown longer, tipped in claw-like black talons that pressed into the soles of her feet, longer and more dextrous. She could see and feel as the symbiote ate through the fat of her body now that it had replaced the organs of her torso, saw fat seeming to melt away as she grew taller, gaunter, gasping and gurgling for air as long-gill like vents opened along her waist, revealing dark blue flesh beneath that sucked at the air. Her frame grew long, lanky, ribs visible and lined with bony nubs at first and then a row of spines that pushed out through the skin, a neat line of white bone protruding along her sternum and along the sides of her torso.
Her heavy breasts, saggy and swaying, were consumed as well, fat eaten as skin tightened, nipples inverting and becoming black and rubbery even as they shrunk down on her torso, bare handfuls on a narrow and emaciated chest. Her collarbones began to stand out against her skin, then poke through, growing a row of small bone spikes in a oval shape ringing her now long and statuesque neck, pale blue skin on a face that was shifting to imperious, cold, sharp. A domineering resting bitch face with narrow lips and a black-fleshed mouth filled with sharp teeth and a drooling tongue that spooled out over her body, reaching down her torso all the way to her own sex as her lank brown hair grew thick, black and silky. Groaning, Mary came as the symbiote began to relax, and her mind began to open as well - pushing out her own orgasm psychically and causing a half dozen other occupants of her building to spontaneously come.
Shaking, quivering, flesh unsweating but cold, Mary sat up and looked at herself in the mirror. Rather than average height and curvy, she was gaunt and well over six feet tall, her feet more like the talons of some dangerous bird. Her skin was pale blue but lined with an intricate web of black veins that showed through rubbery flesh, pulsating far slower than a human heart. Glowing fluids leaked from her mouth and pussy, where her labia had become long, lacey and seemingly prehensile. Her clitoris, currently hidden, was a tapering cobalt teardrop the size of her thumb when engorged. She was dangerously thin, and inch long spines of ivory bone protruded from her collarbone, sternum, and ribcage. Her face had grown as imperious and fitting for a mistress as Sencia no doubt imagined, and her mouth was filled with curving needle-sharp fangs and a tongue capable of unspooling to several feet.
But it was her mind that startled her the most. She could feel Sencia inside herself, almost a seperate being but not quite, and could feel through Sencia's powerful psionic powers the dozens of people currently recovering from shocking sudden orgasms. Panting and staring at herself, Mary gently touched her face and tried desperately to think just what she would do next.