He faded in and out of a sleep-like state that wasn't quite sleep. Once he discovered that he had no need to breath or eat, the steady deep heartbeat echoing in his head became very soothing. He felt warm and safe, content to float in darkness.
For a long time, it seemed that he was getting smaller. The womb around him expanded, and his arms and legs felt like they were shrinking, losing form. On one of his rare periods of thought, Ken wondered if he was doomed to keep getting younger until he was nothing more than a single sperm wriggling in the testicles of some animal. Even that did not really scare him - it was impossible to feel fear in the womb.
After what seemed like a very long time, Ken realized he had started growing again. But not into a human. What he was becoming was unclear, but he knew he now had four legs and lacked any kind of fingers. Slowly, ever so slowly, the womb closed in around him again, until he woke to a sudden squeezing.
For the first time in what felt like years, Ken felt fear. He was being forced out of the womb! The pressure forced him into a narrow tube, his forelegs stretched out in front with a very long face between them. Fingers closed around what might have been his wrists as a human, and pulled.
Ken slid out into dim light and gave a shuddering coarse little bray as his lungs took in their first air. There were people around, people that looked familiar. Mr. Perkins, who owned the farm where they bought vegetables. And his son and daughter, Andy and Mabel. They wiped him clean of the slick afterbirth.
Ken's nose filled with strange smells - sweat, hay, urine, and a hundred other odors. But overpowering them all was the scent from the large donkey that looked at him from behind Mabel. Ken suddenly had to stand, had to walk, had to nurse. Instinct was in control, and before he knew it, he was pulling at the donkey's swollen black teats.
It wasn't until after he had filled his belly that Ken was able to think clearly again. Well, as clearly as a boy with the brain of a donkey could think. For he realized Circe had caused him to be reborn as a common work animal. A donkey.
As Andy brushed him for the first time, a couple of other things became obvious. The boy grooming him had been a couple of years younger than Ken - now he looked to be almost 16. Ken must have been carried full term in the mare's womb - a year!
However, the biggest surprise came when Andy began cleaning around Ken's rump. While a newborn didn't have much between its legs anyway, it became immediately obvious that Ken was a filly. In a few years, he'd be delivering foals of his own!