A Perverted Nun's Plan (Fate/Grand Order)

A/N: A Perverted Nun's Plan was a commission originally written back in April of 2021. Posting it up here and now for people to enjoy!

Themes: Futa Sex, Tentacle Sex, Breeding

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"Well… I think, after all is said and done, that I know exactly what you two need."

The tone that the Perverted Nun uses puts both Caenis and Mordred on edge as they share an angry, frustrated glance. On the one hand, both of them know deep down that they each have their… issues. On the other, it was not their choice to come here and have a therapy session with Kiara. No, rather, it was their Master, Ritsuka, who had sent them here.

According to the Master of Chaldea, Ritsuka Fujimaru, both Caenis and Mordred needed therapy to deal with their 'gender issues'. Frankly, neither of them saw a point to this. They were Heroic Spirits, summoned to fight for the Earth's survival, nothing more. But Ritsuka was a tender soul, and in some ways, much too soft to be Chaldea's Master.

Except when the mental 'health' of the Servants was concerned, apparently. The soft Master of Chaldea had sent them here with the power of a Command Seal of all things backing the order! It was unconscionable, that Ritsuka would use one of the three Command Seals allotted each day to handle dozens of Servants, just on making sure they went to therapy.

In a way, Caenis and Mordred were undeniably flattered. That their Master cared for them that much was not lost on either of them. It softened the blow of their choice being taken from them just a little bit. But only a little bit! Neither Poseidon's Proxy nor the Knight of Treachery wanted anything to do with Kiara! Ritsuka's insistence in seeing the best in every Servant summoned to Chaldea blinded the Master to Kiara's perversion, but they were not blinded!

Though, it could be said that the nun had been… perfectly fine so far. In fact, the three of them had actually been talking for the past hour about Caenis and Mordred, much to their mutual disdain. The two were forced to confront a great number of things about themselves thanks to Kiara, and though neither of them would be thanking her for it any time soon, if these sessions continued as they were and weeks or possibly even months went by, they might come to be grateful.

Of course, the key words hidden in that whole spiel were actually 'as they were'. As in, IF these sessions continued in this vein, then both Caenis and Mordred might come to be grateful. As it was… that wasn't in the cards. Not at all.

"Yes… I can see that I'll have to prescribe you both a very specific… mm, cure. For one, you'll both be attending weekly sessions with me for the foreseeable future."

Both Caenis and Mordred scowl at that, Mordred even crossing her arms over her insubstantial chest in a distinct huff. The two Servants are already thinking up arguments to make Ritsuka back off. Without the Command Seal, Kiara can't make either of them do a single thing after all. But if Ritsuka really does waste a Command Seal on them once a week… well, that will damage Chaldea, won't it?

"On top of that, I feel that it's only right that I prescribe an injection of hot, sticky semen straight to both of your wombs, twice a week."

And then the ball drops, as the nun's large futa cock causes a tent to form in her habit, and a lewd, wicked, honest smile stretches across from face, splitting her cheeks from ear to ear almost unnaturally.

"W-What?!"

"E-Excuse me?!"

Both Caenis and Mordred are understandably outraged at the idea, even as their eyes flicker between the tent in Kiara's lap and the perverted nun's face.

Giggling behind a raised hand, Kiara's eyes twinkle.

"Well, the two of you have such difficulty with your gender. There's only one solution, as far as I can see it! I'll have to impregnate you both. Only then will you accept the simple truth… you're beautiful women, broodmares meant to be fucked and knocked up. Not all this silly galivanting about with swords and spears and armor that the two of you do."

The two women sputter in shock at that, finding it harder and harder to keep their eyes off of the tent in Kiara's nun habit. Her massive futa member is certainly on the larger sign that either of them would ever have seen… if either of them had ever seen a cock before at all. The thought of the two warrior women being a pair of virgins makes Kiara's cock jump with excitement beneath her habit, and she lets out a truly perverse giggle that deeply unsettles both of her… clients. Clients sounds better than victims, certainly.

"You c-can't… I won't go along with this!"

"Neither will I! This is NOT what Master had in mind?"

"Oh? Did the Master of Chaldea not give you both over into my care? Did Ritsuka not demand that you two do whatever I say to help you get over your respective issues? And with the power of a Command Seal, no less...

She trails off briefly there, smirking as both Caenis and Mordred sit stiffly in rising horror.

"As your… mm, therapist, it is my duty to do everything in my power to help you. I have decreed the method by which I shall help you. All that is left is for you two… to obey."

Sharing a look, their faces fall as Caenis, and Mordred realize that neither of them has a way out of this. When they'd rightfully thought that this wasn't what Ritsuka had in mind, the Command Seal hadn't pressured them. But now that Kiara has spelt it out like she did so… academically, they can feel the pressure of the Command Seals on the back of their minds, egging them on, forcing them to obey, to bend to this despicable sadistic futa nun's will.

Shuddering, they both glare at her, neither of them saying another word. But Kiara wouldn't be who she is if she couldn't read surrender etched into the faces of those who were still trying to put on a show of defiance. Letting out a lustful giggle… the nun suddenly explodes forward from her seat, while at the same time not moving at all.

In truth, it's the tentacles that explode forward, her habit being lifted away by them as they reach out from her body and grab at Caenis and Mordred. The two Heroic Spirits can only yelp and squeal as they're lifted into the air and held aloft. At the same time, the removal of Kiara's habit also reveals her massive, fat, futa cock. Throbbing and pulsating with need, she strokes it delicately with one of her actual hands, even as she brushes the knuckles of her other hand against one of her tentacles.

"Relax, girls. There's no reason this can't be… fun."

Letting out another giggle, though this one sounds a lot more like a cackle, Kiara sets to work stripping both Caenis and Mordred out of their respective clothes. The two squirm, but don't fight nearly as hard as they could. They struggle but can't bring themselves to use any of their real strength or power to break free because of the Command Seal.

Soon enough, they're both naked. Looking them both over, Kiara hums for a moment… and then stuffs two of her tentacles into their mouths, which are open because they're both panting at this point. The aphrodisiac-laden tentacles are doing their work, but a direct infusion of their fluids… yes, that does the trick.

The two are soon moaning and writhing in her grasp, and with a wicked grin on her lips, the tentacle nun finally stands up, moving towards them both. When she pulls the tentacles out of their throats, Caenis and Mordred can only gaze around hazily, their tongues rolling out of their mouths, tasting the air and seeking something to play with, to suck on.

She almost gives them her big fat futa cock… but that's not why they're here, is it? No, Kiara needs to break the little bitches properly, and oral sex just won't cut it! Giggling, she slaps her futa prick down on their flushed faces anyways, back and forth as they moan and wiggle their tongues across her shaft.

"Now then, which of you should I start with? Who wants the first injection, hmmm?"

They'd probably both be begging for it, if they were capable of speech. Though, if they were capable of speech, they probably wouldn't be out of their right minds enough to be moaning so wantonly. In which case, they would be cussing her out, not begging for it. All the same, Kiara doesn't get a straight answer from either of them… and so in the end, she has to play a little game.

"Eenie… meenie… minie… moe~"

Back and forth she slaps her cock down onto their faces, until finally, she lands on Caenis. With another giggle, the futa nun lifts the dark-skinned fighter up into the air and promptly spins her around. She's facing Mordred as Kiara steps up behind her and grabs her by her thicc hips, holding them steady and bringing the fat futa cock she's rocking up to Caenis' pussy lips.

Before she can even get inside of the dark-skinned Heroic Spirit, the sound of sucking and slurping catches her attention. Looking over the top of Caenis' head, Kiara coos when she finds that she and Mordred have started kissing, the two heated, turned on women making out with one another.

"Aww~ Such progress! This is going to be FUN!"

She punctuates her statement by thrusting into Caenis from behind, making the white-haired Servant squeal into Mordred's mouth. Of course, she's not idle with Mordred either. Her tentacles restrict themselves to simply holding Caenis aloft for her while she fucks her silly from behind, but for Mordred, Kiara lets her tentacles prepare the Knight of Treachery for her… cumming.

In and out, both Kiara's futa cock and her massive tentacles piston, fucking Caenis from one end and Mordred from the other as the two Heroic Spirits makeout in a truly adorable way. Oops, Kiara forgot to check if Caenis was a virgin when she thrust into her at first… and now she can't remember if there was anything in the way or not.

Would a Servant even be summoned with a hymen, even if they were a virgin? Kiara thinks about it for a moment before shrugging and setting it aside. It was definitely something she would investigate later. For now, she had a pair of sluts to break in properly~

"That's it! Take it, you gorgeous little treat! Take my cock!"

Pounding into Caenis from behind, Kiara doesn't even hesitate. After all… she's trying to break them. Mentally, if not physically, she wants to ruin these two little cunts. The Master of Chaldea was concerned because Caenis and Mordred didn't seem to think of themselves as women. Well, when Kiara was done with them, they wouldn't even see themselves as human or spirit anymore! They would be broken at her feet, her lovely, willing slaves!

It was high time that Kiara begin her take over of this facility, of the Chaldea Organization. It was high time that that Master learn not all Servants could be so easily controlled. Licking her lips at the thought of it, of all of the beauties for Kiara to toy and play with and break upon her cock, she picks up the pace, fucking Caenis even harder, causing the dark-skinned Servant to cum again and again on her thick fat futa member.

Finally, Kiara spills her seed deep inside of Caenis' womb, giving the other spirit the injection of semen that she'd promised. After blowing her hot, sticky load all across Caenis insides, one might think that Kiara needed a break… but no, she was just getting started. Thoroughly turned on, her lusts fully roused by this point, the futa nun cackles gleefully as she pulls out of Caenis and has her tentacles spin both her and Mordred around.

The end result is that Caenis takes Mordred's place and Mordred takes Caenis'. The same tentacle that was preparing the blonde Knight for Kiara's cock now stuffs itself into Caenis' twat in order to properly… plug up the dark-skinned woman. Meanwhile, Kiara places her hands on Mordred's much skinnier hips, grabbing them tightly as she grins wickedly and places her cockhead up against the blonde's prepared entrance.

"Your turn, bitch."

And then she's inside of Mordred as well, fucking away at the Knight of Treachery with all her might. For her part, Mordred is primed and ready to go. She cums quickly, and once she starts, she doesn't seem to stop, moaning into Caenis' mouth as the two Servants continue their makeout session all while Kiara defiles and breaks them in, fucking them silly on her cock.

Crooning, the lecherous, treacherous nun doesn't let up, not even for a second.

"You two will be my first. You two will be my vanguard~ I will break you and reshape you, molding you both to my will. I will make you into the breeding toys I need to begin my conquest of this place!"

She can just imagine it, taking over Chaldea one bitchy female servant at a time. There are so many to fuck, so little time to do it in, and it's long past time Kiara got started on making her presence known! Just because she looked like a simple nun, the Master of Chaldea had never even looked twice at her, had never even tried to get to know her!

And then, Ritsuka had dumped these two in her lap! Foolish, foolish Master!

Cackling evilly, Kiara plows Mordred just as deeply as she did Caenis. She reshapes the blonde's pussy to her thick fat futa cock and doesn't let up until once again, the release rises up within her. Cresting over the top, she cums deep inside of Mordred's drooling quim, filling her womb with her hot, sticky seed right there on the spot.

Even as she pulls out of Mordred, Kiara isn't done. The tentacles certainly don't stop fucking the two Servants as they continue to kiss. Her futa cock is still rock hard, as she strokes it, circling around the two and considering what she wants to do next, how she wants to proceed.

"This… this is only the beginning, you two. Prepare yourselves. The fun is just starting~"

-x-X-x-

Hours upon hours later, Kiara shudders in orgasmic bliss as she paints Caenis and Mordred with her seed one final time, positively coating them both in her jizz, the perverted futa nun looks upon her work… and is well-pleased.

Laid out sprawling on the floor before her, her first two conquests have been soundly fucked, the both of them. She'd taken them one after the other with her real cock, while continuing to physically break them with her tentacles regardless of which one she was truly inside. Fucking them was an enjoyable experience, especially given how she'd had to hold herself back for so long.

Hiding her true nature was exhausting, while this… this had been positively exhilarating. The Command Seal that the Chaldean Master had put on these two would probably have worn off by now, but Kiara knew that didn't matter anymore. She'd given these two her all, while also releasing all of the tension and buildup within her over these past few weeks. If they weren't broken into her loyal, adoring slaves by this point, Kiara would begin to doubt her abilities, truth be told.

They would-

"That was… that was amazing."

"D-Damn straight. Holy shit you fucked the shit out of us…"

Blinking owlishly, Kiara looks down at the two cum-covered girls again to see them both with their eyes open and looking up at her. They shouldn't be awake so quickly, nor capable of speech. They shouldn't-

Before she can even complete THAT thought, Mordred and Caenis are suddenly on their feet. For an instant, Kiara begins to rear back, sure that they're about to attack her. But they move too fast for her to follow, the Command Seal no longer holding them back. In a split second, they've both grabbed ahold of her… or rather, latched onto her arms, wrapping their own arms around her limbs and hugging her arms to their meager chests as they smile up at her adoringly.

"You gave it to us good, Ms. Nun. You almost certainly knocked us both up!"

"That's right! And since you've done that and made us your women, you'd better take responsibility!"

Kiara just… gapes. This wasn't how this was supposed to go. They were supposed to be her mind broken, addled SLAVES. Not… this in between state. Unbeknownst to Kiara, there was a simple reason that not everything had gone according to her original plan. Both Caenis and Mordred were Knight Classes. She knew that of course, but what she didn't understand was quite what that meant.

Namely, Knight Classes were resistance to damage from Alter Egos. Which is exactly what Kiara was. As had as she'd worked, Caenis and Mordred were never going to break that easily. Instead, they'd both become enamored with the futanari nun. They knew what they wanted, and Kiara was helpless in the face of their overwhelming desire.

Sensing her plans for taking over Chaldea any time soon crashing and burning before her eyes, Kiara just sighs… and smiles as she reaches up to pat both Caenis and Mordred atop their heads.

"Well… I suppose it's been a while since I had a pair of sexy wives such as yourselves."

She wasn't giving up, far from it. But… the plan couldn't go forward if these two weren't completely broken. And neither of them were going to let her out of their sight any time soon, Kiara could already tell. So for now, she would have to settle for having inadvertently seduced the two Servants into becoming her adoring, impregnated wives.

… It still probably wasn't what the Master of Chaldea had wanted, so at least Kiara would be able to laugh at the look on Ritsuka's face when the Chaldean Master found out. It was the small things, sometimes…

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