"I must apologize for lying to you, Kaes. It's become a habit, over the years. I can't remember how many times that lab broke me down and rebuilt me. We ran for a time, too, before we found a family to take us in. My name isn't really Rarity, and my sister isn't really Sweetie Belle. It's us. Kaet and Kaef."
The robotics lab called it the KAE project. KAE for Kinshen Acquisition Escapade. KAE:S was built to summon the Kinshen; KAE:F to begin the fight; KAE:A to continue the assault; KAE:T to trap them; and KAE:G to guard. Many trial runs were run, every robot rebuilt many times. But the AI that had been programmed to control the robots was capable of thinking like a pony, the body capable of running off of pony food. They had been meant to pass as ponies, traveling from place to place, gathering what was needed to summon the Kinshen. Some Kinshen were also only possible to summon outside of certain areas, so being pony like would be necessary to capture curtain ones.
The KAE bots were property, but they were also ponies, in a way. So when each was separated, thinking the others were dead, due to lack of evidence otherwise, they ran. Kaet and Kaef were the only two to find each other before Kaes came to Ponyville. They welcomed her into their family, introducing her as a third sister to the others, and everypony else welcomed her, too. Rarity was right, she didn't like Pinkie Pie all that much, but she was capable of putting up with her, none the less. All and all, it seemed a perfect fairy tale ending. And those endings are too good to be true.
"Machines don't have souls, Kaes." The darkness of the Everfree forest swirled around the robot, the pentagram on her flank glowing with her horn, and matching the one on the ground. "And you were built to destroy me. Why should I cooperate with you?" The Kinshen stood in the circle, his eyes glowing red. Kaes stared hard at him.
"I wasn't built to destroy you. I was built to summon you. And once you're done with what I tell you, you're free to help yourself to anyone from that lab." She opened up her saddlebag, withdrawing a full ripe fruit. "Or I could give you this soul fruit, if offering you their souls will make you go on an 'Ethics and Hypocrisy' tangent. They thought they could do whatever they wanted to me just because I have a memory chip keeping track of what happens instead of a flesh organ. That just means I remember who's wronged me better."
The Kinshen shrugged. "What do you want me to do, then, for the price of a soul fruit?"
"Kill them."
"Figures. Alright. I'll do it, and maybe I'll eat some of their souls anyways. It's be a shame to waste them."
"Go ahead."
"I'll be back to claim that when I'm done." Robot and Kinshen grasped hooves for just a moment, and then the Kinshen flew off to do what he'd been told.
Rarity led Kaes into her shop. The odd pony had taken some prompting to introduce herself, but Rarity had had to to make the effort. Kaes certainly didn't seem like she would take kindly to Pinkie Pie. "Well, Kaes, why don't you tell me a bit about yourself? Where you're from, perhaps?" Kaes shuffled her hooves, looked down, and sighed.
"I've been running for nearly as long as I remember." She began. "My siblings and I were born and spent the first years of our lives in a lab. The ponies there thought they owned us, but how can you own a pony that can think for themselves? They treated us horribly, testing our limits, breaking our bodies and souls every time we couldn't do what they forced upon us. By the time I got out... I was the only one left. Or at least, I think I was. They separated us when we weren't testing, but they might have started testing us alone. What had they done to us? What had they done that made them think we could do those things?" Rarity was beginning to see it. Ponies disappearing one by one, some before your eyes, some behind closed doors, some inside a fog where you didn't know if they were gone or not. The fear streaming through your system as you-- "I guess I'll never know." Kaes finished. She put her head on her hooves.
"It sounds like you need some tea." Rarity said. "Wait here, I'll put the kettle on, and start making some bicuits." Kaes nodded thanks. Tea was clearly what was needed.
"More subjects came in a lot. None of us had our cutie marks. I got mine later than I should have." She looked down at the cloak covering her flank. "It's not anything useful, anyways."
"Now, now, darling. You mustn't be such a downer. Here, have some tea. Biscuits will be ready soon enough." Kaes drank down her tea in and instant and held out her cup for more. Her magic was a dark red. Rarity poured more tea.
"Thank you so much! Nopony's ever been nice to me before."
"Well--"
"I'm home!" Sweetie Belle entered the room. "Oh? Who're you?" She looked at Kaes in interest.
"Sweetie Belle, this is Kaes. Kaes, this is Sweetie Belle."
"Kaes? As in--"
"Yes, I do believe so. Kaes as in KAE:S." Kaes froze.