[Genderswap, Twinning]

Wu Zetian. A ruthless and bratty empress who got what she wanted when she wanted it. And those that tried to show her any kind of resistance, those that tried to fight back against her orders, they were usually made to face execution. That was usually how things went back when she was alive. Back when she was at her peak.

But after being summoned in the guise of a young girl in the pursuit of Human History's survival at the hands of Chaldea, things subtly changed. She wasn't sure how or why it had happened, but her needs and her whims had been tempered. Her bratty need had slowly but surely petered out, and there only seemed to be one proper explanation for this change.

It was her Master, Fujimaru Ritsuka, who seemed to be to blame. His endless optimism and his infectious smile had managed to worm its way into many of the Servants that served Chaldea. If not for him, many probably would be up to their usual antics. Whether those antics were harmless or truly evil, he seemed to be the lynchpin in everything.

And admittedly, she had developed a few feelings for the young man. Of course she didn't consider him on the level of a consort, but the way that he treated her with a gentle hand and always did what she asked, while still admonishing her for being so impatient... It was like she felt shame at disappointing him.

I-It certainly didn't help that he had been giving her gentle hugs and pets whenever she fell in line with the way that he thought a girl like her should act. It was... It was not at all why she had become so toothless. Neither were the compliments and respect he showed towards her position, always calling her Empress whenever he wanted to impress her. Which... Which was all the time...

Ahh, just thinking about him was making her a mixture of embarrassed and furious. But that was why she had concocted this latest plan of hers. This plan would directly ensure that not only would he stop spoiling her and pampering her like she was little more than a defenseless child.

She was an Assassin after all. And if there was one thing that she had gotten better at ever since she manifested as a Servant, it was crafting powerful poisons that would lead anybody to obediently follow her commands. Whether it was one of those maddening Berserkers that would otherwise be completely untameable, or somebody like him.

All it required was a simple situation that he wouldn't be able to turn down. And since he had the habit of underestimating girls like her, treating her more like a child while still respecting her authority, there was one way that she could strike at him without him even realizing that he had been outplayed.

Even if the mere concept of what she was about to do was making her wicked heart spin inside of her chest. If it meant that he would stop treating her like this, then she'd do it without hesitation...

---

Ritsuka was having a rather pleasant day, all things considered. Sure, the Yandere trio had tried to lock him away to keep him all to themselves. Sure, Heracles had managed to destroy a block all on his own due to a feud with one of his fellow greeks. And sure, Nobunaga had tried to claim the rest as her own territory because she was too drunk. But most of those things were solved through his care and his nurture, and especially his gentle voice because there was no way that they could keep up their hostile efforts when he tried to dissuade them.

But because he had to defuse all of those dangerous situations, there was one critical part of his routine that he had been neglecting. Around this time, right before noon struck, he was supposed to bring all the children of Chaldea a cup of milk. Even though none of them were able to grow up and reach adulthood due to the nature of their existence, that didn't mean that he wanted them to neglect themselves. They were still human, even if they weren't able to live their lives like they were.

And as he arrived in the mess hall, ready to warm up a bunch of cups of milk so he could carry them off to the various children, he saw a familiar sight behind the counter. Which not only managed to shock him enough to stop right in front of it, but also stutter in surprise as he looked straight at the purple-haired despot.

"Empress? What in the world are you doing?" Ritsuka honestly couldn't believe it. The tiny despot that had entered his service, that wonderful little Wu Zetian, was standing behind a counter like a commoner. Well, granted, it was something that he had tried to help her learn. He wanted her to gain a bit more commonality with her people, even if there was nobody that she could rule over at the present. He wanted to imprint upon her and make her better for the future, should anybody be able to summon her after she left his service.

Wu laughed and covered her wicked grin with a fan. "Oh? You're asking me what I'm doing? That's awfully out of turn, is it not? You should be on your knees, begging to know what I might be doing!" She shouted in such a bratty manner, yet it was several octaves softer than when she was first summoned. She had definitely learned the value of being soft, even if she was still as bratty as ever.

Ritsuka really wanted to hurry along and get those cups heated, but he also wanted to know what his Servant was doing. So he did as she asked, getting down on both knees and pressing his head against the ground to make sure that she couldn't possibly mistake this for anything but the most devoted type of begging. "Empress Wu, please. Enlighten me, let me understand why you find yourself behind that counter."

Ah. There it was. One of the reasons why she couldn't keep up her bratty mood for long. The way he just did exactly what she asked with just... Way too much enthusiasm. It made her blush and cross her arms as she tried to keep a straight face. No, he mustn't get to her. He was beneath her. He was her Servant, not the other way around.

"Well, if you truly must know, I wished to make myself a drink. Nothing more, nothing less. However, when I managed to balance all the flavors just right, I found that it was rather tasty. Far too tasty for me to just keep all to myself. So rejoice! You will have the opportunity to have a taste for yourself!" She cackled and laughed almost like a much older woman should, all while planting a simple jug full of something questionable.

It was a deep purple liquid. Which instantly identified it as something he wasn't supposed to drink. It was probably a poison, if he had to be entirely honest. And yet at the same time, how could he possibly turn down a drink from his beloved Empress? Okay, he could, but then she'd get even brattier and then he'd be taking several steps back. He hadn't worked so hard to try and take care of the younger Servants, just to see them return to their original and horrible ways.

"Are there any benefits to drinking it, Empress?" Ritsuka asked as he casually poured himself a glass. He wasn't going to not drink it, but he just wanted to hear it from her mouth. Considering her skills with poisons, there was a very big chance that it could have an opposite effect. After all, if you knew how to kill somebody, you probably knew how to cure them as well.

Wu laughed in turn. "Benefits? You truly want to hear bene-" She tried to act as smug as possible, only for the boy to nearly slam his face straight into the floor to make sure that she understood that he was begging her as he should. "G-Give me a moment to gloat before you go ahead and act so obedient!" She cried out, her face turning bright red in a mixture of shock and shame.

He just kept his face pinned against the ground. He wouldn't dare embarrass her by saying another word. Which just embarrassed her further. Oh, she was definitely going to fix him so he wouldn't treat her like this. It was one thing to respect and adore her, and it was another to exaggerate that kind of behavior just because she looked so much younger than any of her fellow rulers.

"As I was saying..." Wu muttered as she narrowed her eyes. "It's healthy, yes. Just like the milk you were probably planning on delivering to all of the other children of Chaldea. Does that satisfy your natural curiosity, boy, or do you need me to embarrass myself even further?" Just looking at him kneeling down like this made her vibrate in mild frustration. He was taking her far too lightly. And yet why did it make her feel good!? She wasn't supposed to feel good because somebody was infantilizing her with his treatment!

Ritsuka chuckled a little as he kept his head bowed down while getting back up onto his feet. "I suppose I'll have to treat them all to a cup if it's really as good as you say it is, Empress. Then they'll look up to you like their older sister, all because of your generosity. I'm sure you'd love that." He said, while carefully spinning the liquid around inside of his cup. He had been careful not to spill a single drop while dropping onto his knees, and now it was time to taste it.

Wu narrowed her eyes further, to the point where you could barely catch a glimpse of the malice within. "Oh, yes. I'm sure that they could learn their place in the world." She muttered as her tone was filled with nothing but contempt. Both for the children that she would have to endure, as well as the boy in front of her. All while she watched him drink away at the concoction.

Truth be told, it really was little more than flavored water. But the flavor itself was the best part. She had extracted her very own flavor, the flavor of one of the greatest rulers of all time, and allowed it to mix with the water. And thanks to the sheer concentrated essence of dignity within it, there was no way that he wouldn't end up changing somehow. He was guaranteed to see her in a new light after this. Whether as her true vassal, or something more...

Or rather, that's what she expected. But as soon as she blinked, the entire jug's worth of liquid had vanished. And she could see a faint purple mist leaving her Master's lips, which in turn made her eyes bulge out in distress. He had swallowed ALL OF IT!? HOW? SHE HAD TAKEN HER EYES OFF HIM FOR A SECOND!

"Aaaahhhh... That really was a tasty drink, Empress!" Ritsuka chimed as he looked at the jug, before sheepishly giggling a little as an equally purple blush made its way onto his cheeks. "Whoops. Looks like I've gone ahead and drunk a little too much. Guess it was way tastier than I thought. Sorry, Empress!" With the way that his words were ever slightly slurring, it was almost like he had ended up intoxicated from drinking it. Something that wouldn't surprise her, with how he tended to end up in festive situations.

She wanted to hit him and torture him after what he had done. But instead she decided to just simply watch him and keep an eye on what might happen. There was still a good chance that the liquid would do something. Poison him into proper obedience, maybe just erode his will and leave him a husk. Whatever was going to happen after he drank way more than she expected him to... Was anybody's guess. She just hoped it would end up in her favor.

Seconds passed. Seconds turned into minutes. And little by little, the chuckling that kept leaving Ritsuka's mouth turned more and more feminine. All while his hair seemed to turn the same shade of purple, all while it slightly receded to reveal his forehead, which was now nice and smooth and almost a little sparkly.

The boy that served as her Master was shrinking bit by bit, his clothes getting awfully too large for him. All while he seemed blissfully unaware of what was happening to him. He just seemed to enjoy the feeling of having gotten intoxicated thanks to the taste of his Empress. He just giggled and nearly planted his face up against the counter. All while slowly becoming more and more like her.

"Mmmmph... This was really good, Empress..." He muttered, though his voice had turned fully feminine at this point. Almost a perfect copy of her own. All while he gently tried to grab the jug to pour a little more into his glass. But he found that he couldn't reach the jug. And that his hands were significantly more delicate and slim. And that he could honestly feel a draft, which was the part that managed to make him slip out of his current state of mind.

Ritsuka blinked a few times as he looked at himself. And he saw a painfully flat chest, a very slim tummy and a shapely set of legs that were all trapped within his shirt. Because he had shrunk to the point where he was almost as tall as the Empress herself. That, and he had a thing between his thighs that wasn't supposed to be there. Where had his funny sausage gone?

Wu couldn't believe what she was looking at. Nor could she have expected that this much concentrated... Okay, she honestly should've expected that drinking so much of her essence and flavor would turn somebody into a complete copy of her. It just bothered her that her Master wasn't too bothered by it. If anything, he seemed more mesmerized by his brand new female body.

"Don't you dare touch that, you don't have permission to play with yourself!" The Empress cried out as she swatted at the boy that now had a copy of her body. Which really made him a girl at this point, which she genuinely had to take note of. Especially since it made him a little cuter... N-No, he wasn't cute, and she wasn't cute like this either! "Act like the body that you now own, or I will personally make sure that you understand the ramifications of your current self!"

"Eehhhh? What's the matter, Empress?" Ritsuka giggled, her tone turning a little playful and bratty. There was no sense of being high and mighty, as she was really just a brat when it came down to it. Especially as she started to climb onto the desk, climbing out of her old outfit in the process. G-Good lord, was she always that curvy? Or was it the way that she was practically trying to seduce herself that made her lithe and slim body look so attractive?

Wu could feel the sweat running down her face as her 'twin' came closer and closer. "G-Get away, get away! Y-You..!" She cried out, her heart beating and smashing against her chest as she tried to get away. All while her eyes were magnetized onto that perfect body. Ah, why did she have to notice all of the best parts of her form when she was in such a critical and crucial situation!?

Her perfect hips! Her slim yet wonderful chest! Her untouched stomach! Her elegant hair! And most importantly that wicked smile that seemed way more playful than ever due to how her Master used it! Aahhhh! She didn't want to screw herself, she didn't want to have this happen to her!

And in the midst of her moment of mental duress, she was even more shocked to feel a pair of lips pressing up against her cheek. It was filled with warmth, just like always. All while she heard her Master giggling as he normally would, which didn't exactly comfort her when that giggle came from her own voice...

"You're cute when you're flustered, Empress." Ritsuka chimed as she crossed her legs and turned towards the rest of the mess hall. All while she could stretch and sigh sweetly, satisfied despite her change. "Your body's really good too, you don't mind if I use it for a while, right?"

"I-I..." Wu didn't know how to respond. She wanted to aggressively deny it. She wanted him to stop defiling her image. There was no way that he was going to impact her reputation in a positive way, so she practically wanted to scream right then and there.

But the feelings inside her heart made it difficult to just shout at her. That, and the fact that the doors to the mess hall suddenly shot open, courtesy of one adorable bespectacled Kouhai, who had no doubt wondered why she couldn't find her Senpai.

"Senpai! You didn't get-" Mash Kyrielight cried out as she tried to find Ritsuka, all while her eyes immediately gravitated towards the two Wu Zetians. Especially the naked one, who caused the young lady's glasses to fog up in shock and awe.

Ritsuka giggled a little more. "Hey, Mash! You mind helping me pick out an outfit that fits this body?" The playful and bratty Master chimed, which just served to break her Kouhai more, as Mash fell onto her knees and nearly passed out while kneeling. "Ehhh? Mash, what's the matter?"

Wu silently just pinched the bridge between her eyes. Her attempt to turn things in her favor had given her... A proverbial sister. At least her Master wouldn't treat her condescendingly any longer. And though she managed to rile her up and make her feel difficult feelings, there was just one thought that bounced around in her mind...

Why did she have to be so damn cute while using her body..!?