When the Controller of Reality is used, it alters the memories of everyone in the world so that everyone thinks the new reality is "normal". The only ones who are immune to this are the Controller's owners. However, it does not leave its owners without the knowledge required to live in the new reality. All one needs to do is remember, such as Chris did when he unmerged from Melanie's balls.
And now, trying to remember the life of the bald eagle she was reincarnated within, she was entirely successful. She remembered living out in the wild, queen of her territory. She remembered using her superior vision to spy fish swimming near the surface of a lake, swooping down and grabbing them out of the water with her talons. She ate other small animals, as well, but fish were her favorite. She remembered the nest she had built with her mate-to-be, and the courtship that led to her being bred. She remembered the feeling as eggs formed within her, and how her cloaca stretched as she pushed them out. The feeling was uncomfortable, but not terrible. And she remembered when her young hatched, raising them into proper eagles alongside her mate. Twice this cycle occurred, in fact. And while she had no idea why she felt the need to do these things in this way, she felt proud.
It was after the second set of young had left the nest, that Chris's memories of the eagle's life ended. That was the point that Chris umerged from her host.
Before then, Chris was a human woman (though in hindsight, not the sort of human Chris was used to existing). Died at the age of 63, perhaps physically 83. Chris's memories of being that woman were fuzzy, perhaps in part due to not wanting to remember how her body deteriorated those last few years. She remembered being reincarnated, though, quite vividly. She awoke nearly in darkness, barely making out leaves and twigs in front of her. She was unable to move, and her body felt very different, lacking any limbs. She realized that she must have died in her sleep, and had found herself reincarnated as someone's body part. And judging by the bad taste in her "mouth", she had a hunch what part of the body she had been reincarnated into. She had heard of people merging themselves into butts, before. Even anuses. The idea never appealed to her. The idea of tasting her owner's waste grossed her out, too much. And now fate seemed to play a joke on her, by making her someone's anus. She figured she had to be. Her "mouth" encompassed her entire being, and there was no feeling of the cushiony cheeks of a butt.
She was about to unmerge from her host right then and there, when suddenly, light entered her vision. The leaves and twigs were pulled away from her face, and she noticed a pair of yellow bird feet at the bottom of her vision. It was then that she realized she wasn't a human's anus, but the cloaca of some sort of bird, vision pointed down and orientated with the bird's tail somewhere above her vision. She had heard of people being reincarnated as the body part of an animal, but that never happened to her as far as she could remember. Granted, it's hard to remember that far back.
The bird started walking, up onto the edge of the nest, unaware that it now played host to a human soul. And then, there was a sense of vertigo as the nest was left behind and she saw the ground far below her. But fall, she did not. The bird she was a part of knew how to fly, and did it well. Once Chris got over her initial panic, she found the view thrilling and majestic, albeit unusual given her perspective. A part of her wished she could look around, see out to the horizon. If she unmerged now, she would be able to, becoming a young copy of her host, complete with her host's memories.
But, she didn't. She decided to stay there, enjoying the view. She may have to endure a nasty purpose in life, but after living in a dying body the last few years of her human life, it was worth it to let the bird live for her. Especially if it meant seeing this view every day.
And it was many days that she spent living as the eagle's cloaca. During that time, she was used for her primary purpose many times. The first time was easily the worst. Her host was sitting on the branch of a tree, when suddenly her view tilted up a bit, and a stream of bird poop was shot through her body and out of her mouth. It might have been quick, but the taste was far worse than the natural taste of herself. It left an aftertaste, too. She wondered if it was really worth it to stay this way. She did, though, and over time, she eventually got used to the taste. Never quite liking it, but no longer hating it.
She also got a first-hand (or maybe first-foot) view of the eagle's meals BEFORE they got ate. Seeing animals like squirrels lifeless in her claws, dangling in her feet as she sometimes carried them off, and knowing that they were being torn to shreds by the bird's beak somewhere outside her vision. She never liked hunting. She hated to see cute fuzzy animals get hurt. But she knew that as soon as she unmerged from her host, she'd gain her host's memories of killing those animals. She'd probably even have to, herself. So this was another facet of her new life she endured.
One day, something unusual happened. (Yes, more unusual than being an eagle's cloaca.) She didn't realize what happened until it was already over. A tingling in her body. The sound of screeching and chirping. And then, her host leaned forward, her world shaking, until she saw the tailfeathers of another bird come into view, followed by his cloaca, "kissing" her madly, as she felt some gross liquid gush into her body.
Chris had just become the most intimate part of a mating ritual.
This was something she never thought she'd experience. While humans have sexual organs, those are all male organs, and aren't used to mate as with animals. So to experience mating for the first time, from this perspective, was special to her. Even if, once again, it was a little gross.
The activity repeated a few more times over the next week, before one day, she felt something large trying to push out behind her. Her whole body painfully stretched, as an egg was pushed out of her into the nest. She had no idea how large an eagle's eggs were, but from her perspective, it was far bigger than her, and she was amazed that something that large could come out of her. Then the egg left her view, as the eagle sat on it, keeping it warm from the winter air.
Two days later, the processed repeated itself, as another egg was pushed out of Chris. The second time seemed no easier than the first. But the third time, two days after, maybe a little.
And so much of her time was spent, up-close and personal with the eggs that her host laid. She still got to see light each day, as the mother-to-be took a break to hunt. The excursion was always brief, though, and she later learned upon acquiring her host's memories that the male eagle was still around, taking care of her.
She wasn't sure how long it was, maybe a month, when the eggs hatched. Only on occasion, when the mother left to grab food, did Chris get to see the fuzzy babies. Though she herself was not technically the mother, she still felt a sense of pride at being an integral part of the chicks' creation. She so wished she could snuggle up with them, but she didn't know how the mother would react at a copy of herself coming out of her cloaca, and she also didn't want to risk endangering the chicks.
And so, Chris continued living as the eagle's cloaca. Until one day, when she realized she no longer heard the chirps of the chicks. The time had come for them to leave the nest. It was at that time that she herself decided to do the same. She had been the eagle's cloaca since last fall. It was now early summer, at the latest.
The unmerging process began, and in doing so she felt her host's memories being copied into her own mind. Chris took her first breath in this life, standing up and seeing her host for the first time: a female bald eagle. Chris herself was now a younger version of that eagle, slightly smaller. And her former host was quite shocked and confused at the duplicate that just emerged from her cloaca. Rather than give the eagle a chance to recover and get violent, Chris gave a happy chirp to her former host, and used her newfound eagle memories to take flight, enjoying the amazing view from an eagle's eyes for the first time.
That was 11 years ago.