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Chaldea. The last bastion against the incineration of Humanity’s history. The single organization that would stand against everything that dared to try and ruin them. And though they didn’t always come out on top with the greatest of ease, they damn well tried. No matter how difficult it seemed. No matter who or what stood in their way.
Whether it was corrupted heroes of yore, rulers banding together to face against their successor, a hero with a complex, scientists drowning the world in fog, rulers opposed to the way a world should be governed, or even a king acting like a god on earth, they had managed to beat them all down. And even allied with a couple of them after the fact, thanks to their nature as Servants.
But the latest fight they went through, against the primordial Mother herself, was one that left them all shaken. Not just because she was a Beast, the most difficult kind of trial that they could face off against, but because of what she had done to the population of Babylonia.
Man. Woman. Children. All twisted into such ugly forms, those of monsters with many mouths and no defined features. The Lahmu was what they were called, and they were endless. So many humans were twisted into them. And every single one of them were out for their blood. Even after some of them managed to struggle against their new nature, they still gave in. Leaving them completely and utterly unable to control themselves as they tried to fight against Chaldea.
It didn’t matter how strong the enemy was. It didn’t matter how many they killed. The Lahmu kept on going until they couldn’t. They were driven by a single minded desire to keep fighting until they had satisfied their Mother’s desire. And if that meant throwing their lives away so recklessly, they’d keep going until the very end.
...But even after her defeat, some stuck around. The few singularities that managed to crop up contained a few of them, every single time. Even after their Mother fell, they managed to persist. Even after they dealt with the demon gods, they stuck around. Because they still needed to fulfill her wishes. And they’d do anything it took.
All so that they could make Mother happy.
---
There was a strange air around Chaldea, ever since the day they managed to beat Tiamat. Gudao, the boy that served as the leader by virtue of his ability to command Servants beyond compare, knew that something had to be up. But he just didn’t understand what it was exactly. Maybe if he had more time, he could figure it out. But he had to keep going off to singularities, so there was no time to dwell on this strange air.
And yet every time he returned, things seemed slightly different. He still couldn’t quite tell what the reason was, but there seemed to be something off about his Servants. Whether it was the height of some of their forms, or the lack of feminine features on some of the females. He chalked it up to stress dealt to his body by the singularities, and pushed on despite that. He didn’t have time to worry.
“Mash, how many more Singularities do I have to deal with?” He asked his kouhai and most trusted Servant, the Shielder known as Mash Kyrielight, about the status of his objectives. He had so much to do that he needed somebody to keep track, especially since he barely got a moment’s rest.
If he had bothered to try and look at her every time he came back home, he would’ve realized that something was wrong. But this time, as he looked straight at her chest, he noticed the critical lack of breasts. And almost immediately, his danger senses rang through his mind.
“Hm? Senpai, what’s wrong?” Mash asked, the eggplant-haired girl tilting her head. All while something bulged down below, making the lack of her breasts even more obvious. Wait, was she even… No, she was definitely a girl. Gudao had seen her naked a couple of times as part of their training exercises, he knew the shape of her body.
The youthful Master slowly grabbed her shoulder as he looked her deep in the eye. “Mash. What’s happening?” He asked, a bit of sweat running down the side of his head. He really hoped that he was just seeing things. Hopefully he just confused her breast size for one of the extremely busty girls…
“...Aha, you finally noticed? You really took this long to realize something was wrong?”
...He was right. He immediately hated himself for being proven right, as he slowly lifted his hand off her shoulder.
Mash grabbed his wrist and smiled as she pulled him closer once more. “Really, Senpai. Do you not look at your friends? Your allies? Are you so focused on saving the world that you didn’t take a moment to think about what might happen if some of them get, oh, invaded?”
He didn’t like what she was implying. Nor did he like the slight purplish color he saw inside her mouth. Neither did he like the teeth that were barely visible inside her throat. “Who are you, and what did you do to Mash!?” He shouted, trying to pull himself away from her. He needed to alert his other Servants, to try and solve this problem before it got worse..!
“Really, you couldn’t figure it out? My, Senpai. You really are an idiot, aren’t you?” The eggplant-haired girl giggled, as she pulled him into a hug, forcing her lips up against his…
All while the bulge down below suddenly rubbed up against his thigh, her giggle intensifying as the boy put two and two together. “N-No way. Y-You’re… You can’t be!” Gudao cried out, the absolute horror dawning on his face.
“I suppose since you’re such a fool, Senpai, I’ll have to spell it out. Even if you got close.” Mash said, as a purple set of teeth climbed out of her throat for a moment. And those teeth started speaking, with a distorted yet human voice that was almost like the girl’s own. “We, the sons of Mother Tiamat, have been infiltrating your little base. Finding our way into your allies, until they’ve become little more than suits for the lot of us to wear. And you never noticed it. Never realizing what a horribly misstep you were committing.”
The boy couldn’t pull away, but he could notice the softer masculine traits on the girl’s face. Combine that with her bulge, and it only made sense why the strange teeth called itself a ‘son’. It had managed to turn her into a boy. And if what the genderswapped girl was saying was true, then… Every single one of the strange traits he had noticed… Was because they were turned into boys.
“You can’t be serious. There’s no way you managed to take over every single one of them… T-They’ve been working alongside me, clearing out your kin! There’s no way..!” Gudao didn’t want to believe it. Despite the evidence being right there in front of him. All he had to do was accept the facts, and he still denied it.
Mash let out a giggle as he put his hands on his ‘Master’s cheeks and put his lips up against his. He thankfully pulled his true form’s teeth back into his throat, the Lahmu controlling him preferring to tease the boy with the body, rather than its true self. “You really keep on denying it, despite everything you see before you. You really are the stupidest idiot, Senpai…” He giggled, licking his lips as his panties tented down below. Oh, he really did enjoy this disgusting body for all of its quirks, despite how inferior it was to his true form…
“T-Then how did you…” The youthful Master said, before the gears started grinding inside his head. “T-The smell. The smell that cropped up every time I came home…” He muttered. No, it couldn’t be…
It was. In fact, it was worse than he thought, because the transformed Shielder was more than happy to show him the source of said smell, as he turned around and grabbed his asscheeks. He spread them ever slightly to let the foul yet subtle smell waft out. “Mmhm. The smell of a hollowed out soul. And you didn’t even think for a second to try and figure out what it could be.” The former girl mocked him even more, before laughing a little as a series of footsteps started to echo from behind him.
“They’re here. Your Servants, come to save you.”
Gudao turned around to look, only to freeze in fear as several more boys, just like the one that had just shown him everything wrong with his current situation, made their way toward him.
Raikou, the maternal Berserker. Scathach, the keen teacher. And Drake, the boisterous Pirate. Each of them were supposed to be older, bustier and more feminine than their competitors. And yet here they were, each of them showing of their newly grown shota cocks, and their utter lack of age considering they looked like boys younger than Jack the Ripper…
“Ara ara. You look pale, Master. Are you afraid of what you’ve realized?” Raikou giggled, his new form seeming like such a contrast to his original one. And yet, he still acted like the sexual tease that he always was. Maybe now it was too potent, considering his cock was currently tenting his bodysuit as he wore literally nothing besides it.
Scathach remained as sharp-eyed as ever, as he glared into the Master’s eyes. “You’re late, Master. This is what happened to me. This immortal body, hollowed out and used as nothing more than a suit for those monsters.” He said, a single finger grazing against the reddened cock underneath his bodysuit. “I’ll have to train you to make up for your mistakes. You best prepare yourself, I won’t give you a chance to rest.”
“Haha! Really, you didn’t notice a damn thing, Master?” Drake laughed, his coat showing off his bare chest and his leggings tented with his surprisingly girthy length. “Really, you should’ve! I’ve been drinking cum out of my Grail ever since we got back from Babylonia, and I’ve been sharing it with all the others! To see my brothers invade them through that cum… Yeah, that’s been a real treat!”
Every single one of them had been converted. And judging by their words, they had been converted ever since he defeated Tiamat. He didn’t hear them invade their bodies. Even when he slept right besides them. He slept through those monsters sinking into them like tentacled worms and… and…
“What’s the matter, Senpai?” Mash giggled right into his ear, his cock pulsing against his ass as he wrapped his arms around him. “Are you afraid? Are you ashamed? You should be, considering what you did. You let me and the others get invaded.” He said, as he slowly but surely started to undress his ‘Master’. Just to rub things in further…
Gudao didn’t struggle. Honestly, as much as he wanted to stop them, that part of his mind was currently locked down by how utterly ashamed he was. And instead, he didn’t do a thing to stop the stripping. If anything, it just aroused him further as cum started drooling from the tip of his cock…
“Ara. He’s into it.” Raikou giggled, slowly rubbing his hand up against his cock with a blush on his maternal yet young face. “Maybe we should have a bit of fun with him. Don’t you think, Scathach?”
Scathach nodded, but he didn’t bother waiting. He headed straight over towards his ‘Master’ and grabbed him, shoving him to the ground where he belonged. “Fun is training. And I have plenty to teach him.” He said, slowly licking his lips as his usual stoic expression melted into one of cruel pleasure.
“Don’t just hog the guy, I want a taste of him too!” Drake cried out as he ran over, squatting down by the Master’s face as he started spreading his cheeks. “Hey, Master, ever had a taste of this? Don’t worry, you’ll get used to it before long if you haven’t. ‘Cuz its your only food for now on, haha!”
Mash giggled as he squatted down by his Master and Senpai’s head, turning around so his ass faced that adorable face. “This is your just reward, Senpai. Your reward for messing up horribly. You really should be proud of yourself for how terribly you did. Not noticing the signs, and killing Mother when she just wanted to coddle you…”
With all of those boys crowding around his face, Raikou joining in shortly afterward to line his ass up as well, there was only one potential thing that could happen. And as much as he wanted to stop it, he wanted to experience it just as much.
*BRRRRRRRRRRRRRRRAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAPPP*
The foul gasses, partly made out of pure filth and waste, partly made out of the remainders of each of the Servants’ spirit origins ground into nothing, poured onto Gudao’s face. He was immediately stunned by the sheer rancid scent, and he would’ve probably ended up throwing up if he was in any better state of mind.
But his cock, throbbing within his pants, controlled him. And he was loving every moment of it. Not because of how repulsive it was. But because it was them showing him how horribly he had screwed up. In the end, the Master that managed to defend Human History…
Was nothing more than a massive masochist with a hardon for younger boys, something the four exploited as each of them took a seat upon his face, acting like he was nothing more than a chair for them.
Even as they sat atop of him, they kept on blasting more and more of their foul scented waste into his mouth. The gas soaking into him, practically corrupting him in the process. But he wouldn’t change. Only his tastes did. The only thing that could get him off from this point forward would be the asses of boys that held a Lahmu inside them, and he would be driven to seek that out more and more.
With the three formerly maternal Servants using him as a seat still, Mash stood up and walked over, trapping his ‘Master’s cock underneath his sole. “You’ll help us and our brothers get more suits, won’t you, Master?” He asked, slowly rubbing that dominant foot up against the submissive masochist’s shaft to try and force the cum out of him.
The Master, utterly ashamed of himself both due to how he had failed and how phenomenal this entire experience felt, couldn’t stop himself from letting out a pitiful cry as he came all over that foot. Relishing in his own worthlessness, and accepting the terms that the shota-suited Lahmu put forth.
“Excellent. Do your best, Senpai.” Mash giggled, just like he always did. Happy to see his Senpai agree.
Happy to bind him to Mother’s service, as they planned to fix Humanity for her...