"So, Agate; come and have a treat. Show Coral what she has to look forward to!"
"Y-Yes, Mistress." You swear you see tears in Agate's eyes as she gives you a last sidelong look. Then she hurries over and kneels between the larger vixen's legs. She leans in, closing her eyes as she inhales the scent of the shemale's dominance. Her whole body convulses with need, and she gives in, taking the canid shaft in her human lips, her delicate fingers coming up to fondle her Mistress' balls.
Junia groans rapturously. She places her black-furred hands against Agate's silver hair, lightly guiding the movements of her slave. Agate's reluctance disappears, and she is soon down to the knot, her throat bulging as she diligently sucks and slurps at the thick cock, desperate for the gift hidden in the balls her hands are worshipping.
"My God..." you whisper, horrified. Mesmerised.
"Goddess," softly giggles a voice next to you. You barely register that Moonstone now stands alongside you. Until, that is, you see that while one of her hands is fingering her dripping snatch, the other is toying with a slender, pink five-inch vulpine cock -- longer than Agate's. With her fur so pure white, you hadn't noticed her sheath. You still don't see any balls.
She winks as she sees you staring at her incongruous member. And then you realise you are also masturbating, and snatch your hands away, angrily balling them into fists. No matter how good it feels, you are NOT jacking off to this!
A few seconds later you hear Junia moan in deep satisfaction, pressing Agate's face snug to her crotch. Agate is also making mufled whimpers of pleasure, her tail now wagging as furiously as Moon's. Junia is obviously unloading into her, shooting her fox seed almost directly into the hybrid's stomach. But you notice with another shock of horror that Agate is also cumming.
And, as she does, her cock is definitely shrinking. While it was a bit below average before, it would still pass for a normal human dick. Now with each spurt of watery fluid, it loses length and girth, until it disappears behind the vixen's thickening thighs. Your eyes trail back up to the witch, breast heaving and jaws hanging open in bliss. Dribbles of thick semen overflow from the human's jaws a moment a before Junia pulls her knot back, allowing Agate to gasp in more fox-scented air before sucking a last few spurts from the tip still in her mouth.
"Ahhh," Junia sighs a few minutes later. She relaxes in the chair, her cock fully slipping out of Agate's hungry lips. Her tail, poking out a hole in the back, is wagging slightly. Agate continues to lick at her cock and balls, cleaning off what fluids managed to escape her, as Junia pets her. Then, "That's a good girl. Now get up and show Coral your changes."
Agate's subdued "Yes Mistress" contrasts jarringly with the fervour of her blowjob. But she rises obediently and turns to face you, though she looks away as she licks cum from her lips, her own fluids drying on her thighs.
You gasp. You had seen her penis shrink, but only now do you take in the other changes. The curves of her body have grown more pronounced; her hips wider, her bust fuller. Her eyes have gone from an ambiguous dark grey-green to a decidedly emerald shade, and her pupils now have an animalistic taper.
Most unnerving, however, is that her nutsack has vanished inside a new, puffy slit that has formed beneath the remnants of her penis. Front-on you can see the latter, still human, but just barely big enough to be distinguished from a large clitoris.
"Humans change at different rates, in different parts," Junia explains as you gape. "Depending on will to resist, mostly. Every time you take beast fluids into your body, you turn into that species; male seed has the strongest effect, followed by milk." She hefts one of her heavy breasts.
"Which makes me especially powerful in that regard. The fluids are also adictive when taken orally -- again, especially cock juice and breast milk. You will, quite literally, need to suckle the species that changed you at least once a week, and the craving will always be there. Fortunately, I can easily supply the needs of three slave girls, and more."
She strokes her hand down her belly, and cradled her balls for emphasis. Despite her lengthy ejaculation, her cock is still poking out of its sheath. Junia continues to play with herself as she talks, clearly enjoying the feelings her display is arousing in you as much as she luxuriates in the afterglow.
"And while beasts naturally have high libido, former humans are even more lustful. Maybe it's because you're transformed by sex; maybe it's because it's your purpose as our sex slaves. Mmm. Maybe it's because deep down humans are just pure sluts." She chuckles. "Whatever the reason, you'll need sex more than food, and find your flesh -- and fur -- much more sensitive, unable to resist any pleasurable touch."
As Junia talks, Agate is providing visual confirmation. She has turned to the side, and has gone from exploring the changes in her body to masturbating. Even though she is clearly humiliated to be exposed in front of you, the needs the vixen's essence instilled in her cannot be denied. Junia continues,
"Other details of the change, like gender, are a mix of owner's preference and slave's... 'inner nature,' I suppose you'd call it. It's a matter of debate which is more influential in the process, but owners generally get what they want, and slaves enjoy it. You, I promise, will be purely female; it's what I want, and what I see in you. Though maybe, if you're a good girl like Moon, I'll gift you a new, foxy dick too. I do enjoy seeing slaves squirt out their useless cum in tribute to me."
I don't want to end up like that, you think to yourself as you look back to Agate. The poor hybrid is trying to suppress moans as her fingers dive in and out of her new cunny. Your fingernails dig into your palms with your resolve. You won't become another vixen slut; you will find a way out of here. Then your head snaps back to Junia as she gives an order.