"You're changing too!" Jen squealed, pointing at her friends ears. Amber reached up and felt her donkey ears growing from her head. Jen's tail exploded from her spine, and pleasure flooded her body.
Jen's donkey cock quickly rose again, but there was another intense feeling also coming from her crotch. Jen slide a shaky hand down to find the source. Lifting her massive balls out of the way, she sees that her pussy is returning. But not a human pussy. It's a jenny cunt, thick, black, and weeping with fluid.
Amber's eyes are locked on her friend's genitals, and she has the sudden urge to go over and ride that cock of Jen's. Her own womanhood starts to pulse and grow. There's a painfully obvious camel toe in her pants, and the fabric becomes soaked with vagina juice. Jen catches the scent of an aroused jenny. She turns around, cock pointed straight at Amber.
Jen let herself be lead by her cock, transfixed on the smelly mass between Amber's legs. It was so enticing, Jen couldn't resist. She stripped the rest of her clothing off, and saw she was covered in donkey fur, and her breasts had large black pegs for nipples. Jen's face extended to a slight muzzle, and her nostrils expanded, letting her inhale more of Amber's arousal.
Throwing her head back like a animal and braying, Jen doesn't hesitate to tear Amber's pants and underwear away and drive her cock home.
"Jen! What are you..." Amber can't finish her sentence, her body is so consumed by the immense pleasure spreading through herself. Her sex holds tight to Jen's donkey cock, like someone glued the two together. Amber obscenely grabs her own chest, kneading her nipples and breasts with such vigor milk starts to seep from the tips.
Below, Amber's clit has poked through her jenny lips. It's black, and the tip looks suspiciously like a penis head. As Jen continues thrusting herself in and out of Amber's snatch, Amber's clit extended further and further from her body. Until her clit is about 7 inches long. At which point it transforms into a penis.
A hole forms at the top, and then the penis disappears into a foreskin. Or what started as a foreskin, and is now a sheath. Amber's crotch and body are just as hairy as Jen's now. Her sheath pulls back to reveal a glistening dick, the head exactly like an animal's. Puckered, with little bumps around the head, the shaft stands tall in front of Amber.
Jen catches a whiff of the cock, and cums. Her load leaks out of Amber's pussy, which clenches around her friend's cock. After milking as much cum from Jen as she can, Amber pulls away. Jen moans, feeling her cock slide out of Amber's folds. She falls back down to the floor exhausted. But Amber still needs a release. So she takes her new donkey dick and jams it into Jen's snatch. Jen lies on the floor, almost literally getting plowed.
Amber feels something lashing against her legs, and looks back to see she too has grown a donkey tail. She looks back down at the half donkey herm she's currently inside. Jen still has her breasts (though substantially larger now) and she got her pussy back. But her body is coated in a fine gray donkey pelt, she had a donkey's tail and ears, and there's a slight muzzle with very large nostrils and buckteeth.
Thought she knows that the lust will probably progress her transformation in to a "jackass girl" Amber can't stop herself either. She starts pumping in and out, while stroking Jen's cock. The leathery, black skin feels incredible in Amber's feminine hands. It sends shivers up and down her spine, and makes her nips stand on end. They're as thick as quarters, and as long as four, maybe five inches. Milk dribbles out, and washes over her balls.
Amber cums, locking in her changes. Her tail continues to swish back and forth as her face pushes forward into a muzzle, and her teeth grow in her mouth. Below her, her feet slowly collapse and reform into hooves, complete with large black nails. Thankfully both girls are left with their human hands, furry but still hands.