Betrayer on a String (FGO Doll TF)

Morded was… a little confused, really. She’d had a good night’s sleep (insofar as “night” was a concept that applied in an expansive underground facility like Chaldea), done some stretches, and had her little wake-up routine. She had nearly left the room to get breakfast when she noticed that something was out of place.

Her room was a fairly spartan affair. She didn't need any dramatic customizations, fancy additions, any decoration in general. She didn’t need the certain comfort objects that many of the younger servants either asked for, or were given without asking, by the older ones. She was an adult and all she needed was a bed, and even that was maybe a bit too comfortable. So why in the name of all that was good was there a plush doll laying on her floor?

The knight lifted the doll up, turning it every which way as she looked for a sign of who it might belong to. No nametag, no nothing - just a doll. ...A doll that looked much like the younger version of Artoria, her rather neglectful parent. Mordred flushed a bit as she realized just who the doll was in the image of. While Artoria herself was Mordred’s arch enemy, Artoria Lily was a kind soul, and even in this strange style with exaggerated proportions… admittedly a bit cute.

“What do you want, small-Father?” she muttered to it, planning to toss it onto her bed so she knew where it was as she asked who’d lost it. But the doll looked up at her with bright, cheery eyes, and she couldn’t make herself be so rough with it. As she set it on her bed more carefully, she wondered again where it had come from.

It looked rather cute sitting there, she had to admit. A bit… lonely though. “Well yeah, that’s what happens when you push everyone away, Father. You should be lonely.” she said, as if it could speak back.

…

“...Oh fine.” Mordred said quietly. Nobody was here, so what would be the harm? She settled on the bed, and took the plush into her arms a bit. It was nothing like an embrace with another person, of course. The doll was cool from it’s time on the floor, and besides that it was rather small. But it was very soft and made a good hug.

She found herself rubbing it’s head idly, generally not thinking about too much. It was nice to just zone out for a bit and relax, she thought. She closed her eyes and lay back in her bed as she did so, allowing herself a minute to not think about anything.

As she rubbed, though, she felt like there was something wrong, something she didn’t know about. She felt a bit weird, but wasn’t sure why - there was a strange pressure in her head, like a headache that wasn’t quite painful yet. She reached up to feel her forehead, and felt a strange texture instead. Did she have a scab there or something? She felt around a bit more, and found that the texture continued.

When she opened her eyes it wasn’t shock or concern. It was because the transformation had continued, and she couldn’t close them anymore. She felt at her face, feeling the soft, textured fabric that had become her skin across her face - including her eyes, which had grown significantly as they shifted to white, black, and green fabric and now took up a significant portion of her face. She felt her face up and noticed as well a wide grin plastered on, which she couldn’t budge. Even her hair had changed, going from a human sort of hair to silken thread.

Even as Mordred was feeling the changes, though, they didn’t stop. More and more of her was turning to soft fabric. She tried to squeeze one of the fabric sections, and felt no pain - and indeed, not the usual resistance of human flesh but one more akin to a stuffed toy distending under her fingers. Her experiments didn’t last long, however - she watched as her fingers merged together into useless mittens, stubs really, lacking even a thumb to grasp with.

The change continued, and she tried to stand - but found that she couldn’t actually get up off her back. Not while the change was going at least, as part of her was fabric stuffed with cotton and part was flesh and blood. The ratio shifted rapidly however, as the change progressed down her body. She couldn’t even shout in frustration, her vocal cords had vanished long before.

The transformation ran its course - as it hit her waist, she felt her internals shifting and being replaced with yet more fluff. Her “plumbing” so to speak was no exception - yet for some reason the, well, bits, remained. Her feet followed her hands in becoming thick, useless, formless caps to her legs. She had become a life-sized plush doll.

It took several minutes for Mordred to stand, trying to force her fluff to move despite the lack of muscles. When she stood up, though, she simply stumbled to the ground - she was not really made to move easily anymore, and with how light she was she had barely anything keeping her stable.

She managed, with the help of her bed, to stand again. It took a few attempts, but she figured out how to walk - it was more a waddle, really, shuffling one foot ahead of the other.

Mordred hadn’t the slightest clue what had happened to her, or why. She had a lot of impotent rage, but that was a familiar feeling. She just had to go find someone, right? Someone would be able to figure out what had happened and why.

She opened the door (slowly, laboriously, after struggling to put enough force on it to make it open) and waddled out into the hall.

-----

The unwilling doll waddled slowly down the halls of Chaldea, having to focus more on balance than anything else to avoid toppling over. She was so focused on that, that she was nearly about to bump into the first Servant she found without realizing they’d been there.

But when she saw who it was, Mordred wanted to turn around and go the other way before they noticed her. The black-haired, well dressed Servant was none other than Semiramis. Just Mordred’s luck that she’d run into her.

Before she could go ahead and turn though, Semiramis noticed her presence. It took her a few moments to process what she was seeing. Then she laughed, loudly and long. “Hahahaha! Could that be Mordred? Surely not,” Semiramis said - but somehow, she knew it was. It was strange, normally she’d be a lot more weirded out by the girl showing up as a plush doll, or anyone else for that matter, but right now she just found it funny. “Something this cute couldn’t be that brat.”

Mordred wanted to scream, or maybe just go find someone else to help. But Semiramis had already seen her predicament - at this point there was nothing for it. She still couldn’t speak, but she could try and pantomime that she was in need of assistance…

Of course, to Semiramis, it looked like incoherent flailing. “An interesting dance, but nothing that tells me what you want.” she said. As Mordred was wildly flailing though, Semiramis noticed something trailing off her back.

Ignoring the wild movements of the doll, Semiramis grabbed her by the shoulder to keep her still (she was so light, there wasn’t much she could do). “Hold still a moment, would you?” she said, grasping the string and pulling.

“I’m just super duper happy to see you!” said Mordred’s voice. It sounded artificial, coming from somewhere inside of her rather than her lips. And the sickeningly sweet tone made Mordred want to gag. At least until she fully processed it.

For some reason, she suddenly was super happy to see Semiramis. So happy she wanted to dance for joy. It was an unnatural feeling, that much was obvious, but she couldn’t really care at that point. She had a sudden, irresistible urge to hug the woman. Mordred internally recoiled from the very idea, but her body certainly didn’t; she leapt into Semiramis’ arms, shocking the Servant.

But then Semiramis relaxed. Mordred was so soft, so very huggable, in this form. And that goofy grin plastered on her face seemed so inviting. So she took it in stride, hugging back. It was fine! She pulled on the string again. “Oh? What was that for, you’re usually so surly~” Semiramis asked the doll as she drew out a response.

“You remind me of my mom!” Mordred’s voice said without her consent, “It’s so lonely without her, I wish she’d come and visit.”

Mordred felt like she was going to vomit. How could such a sappy thing come out of her… well, it didn’t come out of her mouth, out of her voice? It was so wrong. And yet it had done so.

And suddenly, she felt relieved. The hug was so comforting. An oasis of calm from the crushing loneliness she suddenly felt. She was so glad to have this kind of hug…

Semiramis withdrew eventually, smiling brightly in a way that looked almost unnatural on her face. “I have an idea. Why don’t you stay with me for a while, until your mom comes?”

Mordred’s body started jumping around, clearly happy - and she definitely felt happy, even though she shouldn’t. Why would she want to stay with Semiramis?

“But first… why don’t you go find some proper clothes? You’re barely wearing anything…”

Mordred nodded. A way out, before she could find herself saying more crazy things and forced to believe them. She rushed off away from Semiramis, at least insofar as she could rush. She had to find someone else, someone who would take her plight seriously…

-----

Mordred was a bit more used to her new build, and could move a bit faster now. She used that to pour on the speed and get away from Semiramis before she said something worse and like, got adopted or something. Whatever had changed her seemed to make her words have an effect on both herself, and on those who heard them. So she needed someone serious and no-nonsense who’d take a look at her and see something was clearly wrong.

Again, she wasn’t paying attention. And this time she did actually bump into someone - specifically someone with a rather generous bust. She bounced right off, too light and fluffy to really cause harm. She barely managed to keep her balance, as she looked to see who she’d stumbled into…

“...Curious.”

Well, the rather large woman in front of her certainly fit the bill for “serious” Servants. Unfortunately for Mordred, it was a version of her father - Artoria, Lancer-class version. Imperious and intimidating as ever, the icy gaze of a monarch fell on Mordred.

She didn’t want Father to see her like this. Least of all this version of her. And if she pulled the string and Mordred said something weird, she was certain she would never hear the end of it. She scrambled away, but hadn’t fully recovered from the initial bump and instead found herself falling to the ground, ass in the air and string fully visible.

“This is not your usual form, Mordred.” Artoria said. She bent down, but when she saw the string, she felt a sudden… compulsion. She had to pull it. What was the harm? “What caused you to be like this?” she asked, as she pulled the string.

Mordred felt a sense of deep dread as she heard herself wind up to answer. “I did,” her voice said, “I’m such a bad knight, it’s better for me to not even be one. I asked Semiramis to make me into a nice doll, so that I’d never even think of being one again. I was coming to tell you, but bumped into you instead! More proof I could never be a knight.”

Artoria frowned. That certainly didn’t sound like Mordred. It was her voice, of course. But not her words. But as Mordred stood and turned to face her, Artoria looked into her innocent drawn-on eyes, and suddenly felt she couldn’t disbelieve her. Surely she was telling the truth. There was nothing strange, nothing to worry about.

“Well, of course, I will accept your decision.” Artoria said. It was just a little… toneless, like she wasn’t all there as she spoke. “You know yourself best. If you so strongly believe that you cannot be a knight as to go this far, then I shall believe it; you clearly should never have been a knight in the first place.”

Mordred wanted to scream out that she hadn’t said that - she not only wanted to be a knight, she was the best damn knight there was! But of course she couldn’t speak, and again her body showed her “appreciation” with a hug. And as she hugged Artoria, those rebellious thoughts dripped out of her head. She had the skills of a knight, but she didn’t need them anymore - one by one, her skill in riding, swordplay, physical training, all of it, were written out of her Saint’s Graph, the core of her being as a Servant. Noble Phantasms and all, vanishing from the very concept of herself. Not only did she not wish to continue to be a knight - by all accounts, she wasn’t anymore, nor could be again. The idea was no longer compatible with her identity.

She was so relieved. She’d been so very worried Father would be mad, or deny her, or force her to go back to knighthood. But of course Father had understood right away. She’d be much better off as a doll, wouldn’t she? She’d said so herself, so it must be true… a

Artoria patted her on the back a bit, before withdrawing. “It is quite mature to recognize your own weaknesses without prompting. I will make certain the others know; I’m sure the other knights, as well as Master, will accept your decision.”

Mordred of course couldn’t verbally respond, but she didn’t do so physically either, standing there with her very identity warring with itself. Artoria didn’t notice, as she waltzed off down the hall to do as she had said.

She wasn’t sure how long she stood there, but it must have been only a couple minutes - she saw Artoria turning a corner. She… she couldn’t let her go tell everyone! Sure, she didn’t want to be a knight anymore - she was far, far better off staying in Chaldea and supporting the other Servants. That new truth was all well and good, but she still didn’t want everyone knowing she had been turned into some doll!

She was just about to run off after her, when she was wrenched back. Or not so much wrenched, as found she could not move any further forward. She turned back, found a hand on her wrist, and followed that hand, and the arm, up to it’s owner…

“Oooh… this is better than I could hope!” Medea, resident stalker of Mordred’s father, practically sang as she pulled Mordred off her feet, and into a bridal carry. “I was planning to follow Lancer, but what do I find? A perfect replica of Artoria, wishing desperately to be a lovely doll! I’ll help you, my lovely doll - you won’t have to be Mordred anymore, you can be Artoria!”

Mordred hadn’t the muscle to resist as Medea physically swept her from her feet and started carrying her down the hall. She tried to struggle, but it was really just pathetic pushing against Medea’s surprisingly strong grip with very weak limbs.

The doll was carried right down to Medea’s room - which at this point had become less a living space and more of a shrine to Artoria. The shelves were covered in assorted figures, one wall was completely covered in what a rambling Medea called “candid” (meaning “sneakily taken without Artoria’s knowledge”) pictures of the various alternate forms of the King of Knights. The ground was mostly covered in stands off of which hung assorted dresses that Medea had hoped to put on Artoria one day.

Or, as Mordred realized as she was plopped down on a chair, on whoever she happened to be able to nab. She was ready for her string to be pulled and another shift in her identity, but as it turned out, Medea had other plans. The witch hadn’t even realized she had that string, and was more occupied picking out a dress for her. Mordred was just about to get up and try and run away, when Medea turned back with an overly elaborate pink and red gown.

“Isn’t it the most wondrous thing?” she asked, “I worked so hard on it, I think a princess-y vibe would look great on you - get the cute side of that whole nobility thing. We can try the other end of it, maid, later. What do you think, try this one first?” Medea rambled at light speed, acting as if Mordred could speak back (and probably having forgotten she wasn’t in fact Artoria).

Mordred was about to shake her head no automatically, when she realized such a dress might hide her string and prevent Medea, or others, from making use of it. ...Also, it was cute, and fit someone who would never be fighting again, like her. But mostly to stop her string being pulled.

Medea beamed, and got to work. Mordred’s next half hour or so was a flurry of silks, brushes, and endless nattering from the witch as she worked. She barely could pay attention as Medea helped her into the ensemble, from corset (which could get surprisingly tight given she didn’t need to breath) to poofy petticoats.

Meanwhile, Mordred was looking for an exit strategy - she had to find a way to get out of there once Medea gave her an opening. The witch stepped back to admire her work. Mordred’s silken hair had been brushed out, straightened and smoothed to a more regal (and more Artoria-ish) look. She was now wearing an elaborate, poofy princess dress, red and pink all over and nothing that anyone would mistake for the attire of a fighter. She looked good in it too - it was a natural fit for her.

“Oooh, nearly perfect… hold still while I get some jewelry…” Medea turned and started rummaging through some boxes on a vanity.

That was Mordred’s chance. But she had to make sure she wouldn’t be pursued by the nutcase - she noticed a makeup bottle on a shelf next to her, where it had been placed in preparation to use it on her. Well, she wasn’t going to let that happen. Mordred picked it up (with difficulty - she didn’t have hands anymore, after all, so she had to sort of press it between her arms) and threw it towards the big old Artoria shrine. There wasn’t much strength in the throw, but the bottle had been loosened already as Medea planned to use it, and it still made enough of a sound. The makeup ran across the shelf and towards some models.

Medea let out an ear-piercing shriek of dismay, and Mordred took that as her cue to leave. She stood up and ran as fast as her bad feet and bulky dress would allow her, running down towards a place she could hopefully find aid.

-----

Da Vinci was anything but serious, but they might be able to figure out that something was wrong and might be able to design something to fix it. She might see it as a challenge or something and have fun with it. That was Mordred’s thought process as she entered the workshop, looking about for a sign of the prolific inventor. She’d thankfully managed to avoid confrontations - there had been other Servants in the halls, but with the dress hiding her string none had had the same compulsion as Artoria and Semiramis to pull it and change her mind further.

Unfortunately, nobody was there - not Da Vinci, not Master, not anyone. She settled on a chair, planning to wait for somebody to arrive and maybe help her out. But as she made herself comfortable, she heard footsteps further in the workshop.

“Mordred, good to see you! You’re looking very fancy - Medea had some fun, didn’t she? Of course she would, with a doll like you.” A female voice said. Mordred turned, to find a certain purple-haired Servant, one of the unique “Moon-Cancer” class (at least, that’s what she called it); BB, the (self proclaimed) mysterious black magus and probably kinda nuts. She struck an overly dramatic pose as the sound of trumpets came from nowhere. “Welcome! You’re the very first to enter the mysterious workshop of this butterfly of the moon, BB! You’ve been having a super fun day, huh?”

Mordred stared for several seconds. She seemed to already know… basically everything that had been going on. And had apparently taken over Da Vinci’s workshop, knowing she’d come. Had she been the one to set up the day’s events? Of course, Mordred couldn’t ask, couldn’t even look questioning as her face was frozen in a cheery grin. What she could do, was stand up, and charge down the purple haired crazy. It wasn’t very in line with how she wanted to be, but Mordred could make an exception for this one-!

Or she could, if BB wasn’t capable of keeping her at bay with a single finger poked at her head. Mordred tried to advance, but she was just a doll, after all - she hadn’t the strength to hurt BB even if she could get close, her brash nature running face first into the troubles of reality.

“You should be happy! The tsun-tsun levels in Chaldea have been crazy high lately, so I’ve got to balance it out somehow. There needs to be a nice, even spread of different types of -deres, you know! You should be happy, you weren’t even that good of a tsundere, waaaay too much tsun-” BB rambled on, occasionally interjecting Japanese words that Mordred didn’t care to ask about.

Whatever her justification was, it was surely insanity. Mordred might not have fully understood what she was on about but she did know that she was being insulting. BB could shove her “tsunderes” and “derederes” up her-

BB seemed to finally take notice of Mordred’s struggle, and casually stepped out of the way, releasing Mordred as she did so. Mordred took a tumble to the ground, ass in the air. Before she could get up, BB put a foot on her, keeping her as firmly in place as if she’d been bolted to the ground. “Awww, thanks for bending over like that! Makes this next part so much easier. I guess that means your change has been working out, huh? Now this next bit’s gonna feel a bit weird, but I promise it’ll feel real good in a minute.”

Mordred struggled, managing to turn her head around to see BB poised over her with something long and phallic in her hands. There was nothing she could do to stop her, as BB placed it up against her ass. Despite not having that kind of biological need, the hole was still there - and seemed almost made for the purpose, as BB rammed it inside. It was a perfect fit, and yet still stretched Mordred like nothing she’d felt before.

To her great dismay, it wasn’t painful. At least, not as painful as it would have been had she been human. While on it’s own that would be a good thing, the thing that really made her wish it had just hurt like hell was that instead, it felt good. Really, really good, mind-blowingly good, leaving Mordred screaming (or would have been with a mouth) with pleasure.

As Mordred writhed on the floor, BB continued to talk as if nothing was off. “The BB Workshop’s opening up soon, and you’ll be first of our new products! Or well, one of the first, had to get a squatter out before I started, but still. Combination dress up doll, comfort pillow, and massager - and whatever else your owner wants~” she paused, thinking. “Hmmm… but it’s not really good branding for the BB Workshop to sell a Mordred doll, is it? Or an Artoria doll, since that’s kinda what Medea made you. Hmmm…” BB made a show of thinking, before snapping her fingers.

She pushed up Mordred’s skirt and reached inside her dress, hand pawing around looking for something. It was immediately obvious what - but even knowing it, Mordred couldn’t stop BB from finding and pulling on her string. “I think I know what you’re called. You’re a BB Doll, aren’t you?”

“Of course, my name is BB Doll!” BB Doll said. She remembered who she’d been still, quite clearly - a knight who didn’t want to be one anymore. But she couldn’t for the life of her remember what her name had been - all she could remember was the “name”, BB Doll.

BB giggled. “That’s right. I should give you a demonstration, hm? I said you’d be a massage doll, but it’s not obvious how, right?” she said. She reached down to the phallic object in BB Doll’s bum, and hit a switch.

If BB Doll had been ashamed of the pleasure before, now she was completely overwhelmed by it. It was too much, her ass shaking every which way as vibrations shook through her whole body. It wasn’t just her rear end, as her whole being shook. BB Doll tried to gather her wits and fight against it, tried to get out from under BB’s heel, but she pulled the string again.

“Good dollys don’t move on their own. You’re a good dolly, aren’t you, BB Doll?”

“I’m a good dolly!” BB Doll said, even as she went limp, unable to move. She wasn’t even sure she wanted to - she knew she could, maybe even should… but she was a good doll… and good dolls didn’t move on their own.

BB took her foot off the now-immobile BB Doll; without motion, an observer would never realize it was anything but what it appeared to be: A life sized plush doll. BB giggled at the sight - this was going perfectly! “Oh, this is such a fun way of doing this…” she said, as she pulled on the string again. It couldn’t just change minds… “BB Doll, don’t you love your long, purple hair? Your bright purple eyes, your super BB-like voice~?”

“Of course! I’m just like BB, and I love it!” BB Doll said cheerfully as the string withdrew, and as she said it, it became true - in more ways than just mental. Even those words had been delivered not in the crass voice of Mordred, but the tones of BB. The doll’s blonde hair got longer and longer, even as the silk shifted in shade to a bright purple. Soon, it was around the doll’s rear end - and even it’s face had shifted to look more like BB’s. And BB Doll, of course, loved it. She loved her look. She remembered who she was, though! This might feel right, but it wasn’t, was it?

“There! Now you look like a BB Doll!” BB laughed, positioning herself for one final pull. “You’re nearly done~ My kouhai powers are truly great!” She said, as she wrenched the string back one more time. “Now, BB Doll - haven’t you always been a doll?”

That was it; no more fighting, no more worries. BB Doll’s memories faded rapidly as the string withdrew into her body. Knights? Being a human, or a Servant? Fighting? None of that for her. She was, and always had been, a BB Doll. She was a lovely doll who loved to be used by living things. She was an object for comfort and pleasure of humans and Servants - nothing more, and she’d never want to be more anyway.

Confident that BB Doll was good and done, BB picked up the limp doll and carried her deeper into the workshop. “Oh, the grand opening will be soon! I wonder how much demand I’ll have? The BB Dolls will be flying off the shelves!” she said, mostly to herself; it wasn’t as if BB Doll could respond. She deposited the doll on a shelf - alongside a dozen completely identical BB Dolls. “If there’s too much demand, I might have to expand the targets to non-tsuns. I’ve got to make sure the balance is juuust right here…”

The former Mordred was lost amongst the crowd of BB Dolls as BB turned away. Not that it would matter at this point; to make a distinction between that specific BB Doll and the others was pointless. They all sat in silence, waiting for the time they would be bought and begin to comfort their owners...