"You know what our shared fetish is." Eric says. "Let's become foxes." Jennifer blushed red. "R-really?" She asks in disbelief. They both had always been interested in foxes, especially their mating cycle. Their hidden desire was to become foxes and mate, even to the point of permanency, ever since they became boyfriend and girlfriend. Now, as husband and wife, they anticipate the changes with arousal. They both strip off their clothes, exposing their nude bodies to their partner for the first time. "I hope you keep those curves when you transform." Eric says as he caresses her form, causing her to moan a bit. "And I hope your fox cock is deep red with a huge knot." Jennifer responds, kissing him. She gets on all fours, ready to trigger the transformation through penetration. The sex wouldn't be interrupted by them becoming feral if they took feral positions at the start. The pieces are in place, as Eric mounts her, penetrating her hymen, beginning the transformation.
Fluffy orange tails sprout from their tail bones, eventually wrapping around each other. Their legs shift to become feral, as orange and white fur grows on their rears. "Jennifer, my cock is changing!" Eric says, as he sees his penis grow, turning red and gaining a big knot, just like she wanted. As their genitals become those of foxes, the fur begins to spread, as their bones and organs shift painlessly. They begin to shrink, as their hands become paws, and their arms become front legs. The two begin to make canine howls as Eric begins to shoot his seed into her, knotting her in the process. Their faces are the last to change, as their teeth become sharp, their tongues extending, as their noses and mouths combine to become vulpine muzzles. The changes soon finish, leaving two knotted red/orange foxes. "What a rush!" Jennifer happily barks, now speaking in the fox language. She licks her husband and mate as he licks her back fur, both taking in the sweet sensation of being knotted. "I love you..." Eric says.