"H-hey, W-wummy right? how about we s-slow downeeeeeeAAIIIIEEEEEEE!!!"
The thick head of the cock thrust forward, ramming into her pussy unrelentingly like a battering ram, shoving aside her lips and forcing its way inside stretching her labia into a lewd O shape, which was a similar shape to her mouth as she opened it wide and screamed.
Kayla came instantly from the rough usage-- a shower of pussy-juice shooting from her tentacle-cock-stuffed snatch spraying over Vivi's cum covered front creating little clear rivulets over the thick layer of gluey cum that had come from her sister.
A long lush moan ripped from Kayla's lips, gods it was so fucking big inside her and she could feel every nodule scraping and rubbing at her walls, dragging and pulling at her nerves in the most impossible ways. She looked down in shock to see something she had only come to expect from Fey, a bulge in her belly outlining the shape of the cock.
"Oh god, oh fuck, noo this can't be happening!" said Kayla as she put her hands over her eyes, her face heating as her breathing massively accelerated. She'd joined the band for Fey, not for some, some slime monster!
By this point, Lily's belly had shrunk down from six foot across to a little over three and a half. She'd sunk downward atop her belly too, until her snatch was more or less level with Vivi's navel.
Vivi gasped aloud as yet more tentacles spread her lower lips uncomfortably wide, stretching her out as they pushed from her labia and slithered over her thighs, rolling and coiling up her body, wrapping around her limbs and coiling tight around them, their immense strength holding the fox girl completely, controlling her fully, like a puppet. Vivi looked down her body fearfully as the tentacles moved her, the slime now fully in control, drawing back from the otterkin girls as even more tentacles wrapped around Kayla, lifting her up into the air.
The nobbly tentacle pumping in and out of Kayla's sloppy gushing folds drew backwards along with the otterkin until it appeared as though the otterkin was speared upon a large cock sticking out from the Vulpine's crotch. Then, in a mirror to Kayla, the central tentacle in Lily's snatch thickened and grew nodules. This left Vivi with a pair of pseudo cocks growing from her groin, each penetrating an otterkin girl.
Vivi let out a muffled yell as the tentacles wrapped around her jerked her hips forward and her two pseudo dicks thrust deep into the twins causing them to cry out in ecstasy as the nodules covered lengths rippled past their folds causing them to arch their backs and grasp at each other.
Vivi shook her head and tried to bite down on the tentacle slowly squirming deeper and deeper into her throat but the simple minded slime seemed to simply take this as an indication it should go harder. Vivi could do nothing as she was made to fuck the two otterkins, her hips moving faster and faster, pistoning to two glossy white pseudo cocks in and out of the two girls, each slamming thrust causing a gush of cum to pour from Lily's pussy.
"Hnnnn! Oh no why does this feel so good!" whined Kayla as she desperately held onto her sister.
"I really didn't expect to be emptied this way! Oh! OOOH!" wailed Lily.
As Vivi's hips thrust the tentacles began to reciprocate from the otterkin's perspective, thrusting them against Vivi as she humped her hips forward, sending Kayla wailing through the air as the bulge in her tummy extended further and further outward. Below her Lily was sent sloshing across her own stomach as her torso was forcibly shifted.
The slime SQUEEED! once more, the sound still muffled, and the pseudo cock tentacle inside of Lily shivered and changed form, the tip opening up.
Lily let out a rising wail as the tentacle inside of her began to suck, the cummy lake in her womb becoming a swirling morass with its own current that centered on the tip of the tentacle. Her pussy clenched down hard as clear squirt exploded out below her pulsing clit even as the nobbled tentacle inside of her grew larger and thicker as it took in the huge amount of horse cum into itself.
Vivi's eyes went wide as she took notice of the rapidly fattening tentacle that led from Lily's deflating belly to her own pussy. This, this was really really not good. Unfortunately she could do absolutely nothing except look on helplessly as the bulging thickness of the tentacle spread up the tentacle's length, the bulge clearly a thick opaque white compared to the transparent glossy white of the rest of the slime. A lot of cum was headed her way and she could do nothing but take it.
And take it she did. She howled around the tentacle in her mouth as her puss was stretched out further and further and her womb became a slurry of pumping cum, pushing out her belly more and more.
Then the cum was directed back out.
She screamed as best she could around the tentacle in her mouth as the other pseudo penis exploded in girth, stretching out her puss in a paper thin ring around the two massively thick nobbled tentacles. The upper tentacle penetrating Kayla had a bulge quadruple its original thickness rolling toward the tip where the hopelessly unprepared Kayla was constrained.
Kayla looked on, eyes like saucers, as the inevitable rolled toward her, her sister's cum, the cum from her sister's womb, it was headed directly toward her pussy. She shook her head frantically, unwilling to accept it, but the slime didn't listen and the bulge crashed against her already straining muff and then began stretching her wider and wider and wider as the tentacle thickened and its nodules scraped ever harder against her pulled taut walls.
She threw her head back and screamed herself silly as the bulge in her belly grew and grew, the size of the dick penetrating her becoming impossibly wide, popping out her belly button with its girth alone. Even the nodules of the tentacle could be seen through her skin as little bumps.
Squirt exploded from her tightly stretched cunt in a high pressure spray, strong enough that much of the cum was washed clean from Vivi's shirt, once more revealing the words "I'm not pregnant, I'm just full of cum!"
Then the tip of the tentacle opened and all of her sister exploded inside of her.
Kayla's eyes rolled up and her tongue lolled from her mouth as the overwhelming sensation of so much fluid stretching her so quickly and violently pushed her over the edge into a rolling orgasm that just didn't stop. The more the non-stop hose of cum sprayed up against her womb, and the more the tentacle twisted and turned in her passage, scraping up her sensitive spots, the higher she rode the crest of ecstasy.
She babbled and cooed as she lost control, barely aware enough to notice that she was slowly sinking earthward, her deflating sister being rapidly covered by her own inflating belly.
They ended up in an exhausted pile, still covered in tentacles, although the tentacles had gone limp by this point. The three girls breathed heavily, their limp hands vaguely grasping at each other, as half lidded eyes saw sightlessly, just processing what they had been put through.
At last Vivi managed to gather herself.
"Please don't tell anyone about Wummy," she gasped.
"You named the slime, you named the dangerous perverted slime monster you are carrying around inside of yourself," murmured Kayla in disbelief.
"Ella will make me get rid of it! I've…I've grown fond, it's my pet! Wummy doesn't mean any harm, it's just enthusiastic!"
Kayla let out a long groan and covered her face with her hands.