Amber kneels down and begins to lick Jennifer's dark anus, toying with it as it slowly relaxes. As Amber gains more and more confidence she inserts her tongue into Jennifer's behind causing Jennifer to let out a large moan distorted by her donkey vocabulary. She can feel Amber's tongue, swirling and dancing in her behind as it begins to change, increasing in length and width, providing Jennifer with both increased pleasure and lubrication.
Amber pulls out her tongue and while savoring Jen's taste, grabs her equine penis and begins rubbing it between Jennifer's ass cheeks, teasing her. Jennifer is shaking on all fours waiting for her friend to hurry up and fuck her. Her mind completely void of all thoughts of returning humanity is now filled with the though of Amber fucking her ass with her long, hard donkey penis. Just the thought made her flaccid penis erect again, it began to throb, aching for release. With her mind preoccupied with sex Jennifer pays little attention to the cramp in her arms and hands. With her head thrown back in ecstasy she hadn't noticed how her fingers had merged together into one black mass. The mass began to solidify and shrink and in a matter of minutes her front two hands were gone, replaced by a pair of shiny hooves.
Ambers heart was beating at a thousand miles an hour. Succumbing to instinct she took position to fuck her best friend hard in the ass. Applying little pressure Jennifer's sopping wet anus gave way for the 16 inch monster. Jennifer groaned and grunted as inch by inch Amber slid into her. Jennifer could barely utter a word as Amber mercilessly thrust in and out of her.
All the while Jennifer's changes began to hasten. Her arms cracked as the bones rotated forming functional front legs. Her hind legs underwent a similar transformation, with her feet melting into hooves like her hands.
"Oh Yes! Oh God Yes! Don't stop! Please! Oh... OH... Heee - Haaaaw!" Jennifer continued to scream in pleasure as Amber picked up her pace. "Jen your ass is fantastic, huff, I wanna, huff, fuck it all day long!".
Her body lengthened further with her large breasts slowly fading into the expanding muscle mass. Fur continued to sprout from every inch of Jennifer's skin until she was completely, the only remnant of her fading humanity is her face.
"Jen! I'm think I'm about to cum". "Meeee Tooo!" Jen replied, speech become increasingly difficult. "OH god here it comes Jen!!" Both girls screamed in unison "I'm Cuuuuuuuuminnnnnhheeeeee-haaaaaw!" And with that final bray Jennifer's face pushed out forming the muzzle of a donkey. Completing her transformation.
Amber still entranced in the afterglow of orgasm fails to notice her friends condition. She slides her penis out of Jennifer's ass and lies on the floor. Suddenly she feels something tickling her penis. "Haha, Jen, that tickles. Hey I didn't say stop!" Amber looks up only to find a large donkey staring back at her. OH NO! Jennifer! I'm so sorry. I never meant for any of this to happen.
Jennifer stood for a second and though. "I can't use the curse on her, because she can't talk.... Think Goddammit!" Suddenly a thought struck her. "I know! I'll pass the curse to someone , daring them to transform me into a human who can transform Jen back! But who do I pick...