Mercedes is a Naughty Slut

Mercedes was in the cathedral, cleaning up after another school day. Everyone else in the cathedral had already left, off to spend the rest of their day in leisure. It had been a good hour or two since Mercedes had been left alone, but she didn't mind. She loved helping around the monastery, whether it was helping soldiers carry around supplies or assisting the cooks in the dining hall. They were all a part of the same community so it made Mercedes happy to help out that community whenever she could.

That's just who Mercedes was, and everyone loved her because of it.

Unbeknownst to her, however, Mercedes had recently garnered attention from a particular individual for very different reasons, and that individual was hoping to get to know her better.

"There, all done," Mercedes said. She looked over the cathedral, feeling good about another job well done.

Hmm, what should I do next? I think Annie said she was going to be studying in the library. I know she's been having some trouble with this week's lessons. Mercedes clapped her hands together and giggled. I'll go surprise her. I'm sure she would love some help.

Just as Mercedes was about to leave, she heard footsteps. She turned around and saw a large man walking towards her. The man seemed out of place in the sanctity of the cathedral. Normally, anyone who saw this man walking towards them would have immediately put their guard up. Mercedes, however, always made it a priority to never judge anyone based on their appearance.

Who's that? I feel like I may have seen him around the monastery. Is he a soldier?

Mercedes never took part in gossip so she wasn't aware of the stigma that the man had gained since arriving at the monastery.

Yet, she couldn’t shake this odd feeling. Something about him seemed…familiar.

"Hello there," Mercedes said while giving a courtesy bow.

"Good afternoon," Kostas replied. "I'm not interrupting, am I?"

"Oh, not at all," Mercedes answered. "I was just about to leave actually."

"It's the middle of the day. Why are you here all alone?" Of course, it wasn't a coincidence that Kostas was here. Manuela told Kostas that Mercedes had a habit of tidying up around the cathedral all on her own, and he figured this would be the perfect opportunity.

"I just like to help around when I can. The staff here work so hard to keep this place clean for all of us, so if I can help lighten the load a little, then I don't mind giving some of my time."

"Huh. You're a really nice person, aren't you?"

"I wouldn't say that," Mercedes said while waving her hand in the air. "I'm not doing anything special. I just like to lend a hand to others, that's all. It's all a part of carrying out the Goddess's will." Suddenly, Mercedes' eyes widened, realizing she had forgotten to introduce herself.

"Oh, my apologies," Mercedes said. "Please forgive my rudeness." Mercedes extended her hand towards Kostas. "My name is Mercedes."

"Kostas," Kostas replied while shaking the girl's hand.

"Kostas. I see. I think I've seen you around. What do you d-"

"Sorry," Kostas interrupted. "I'm really not in the mood for small talk right now."

"Huh?" Mercedes said. She paused, momentarily confused by the bluntness of his statement.

Kostas's devilish grin appeared on his face. "You seemed very nice, but it's time to forget about your old life."

Before Mercedes could respond, Kostas let out a single word. "Slut."

Mercedes's eyes immediately went vacant, as the words that Manuela taught her emerged from her deep subconscious: Obey. Slut. Cock. Obey. Master. ****. Obey. Her arms dropped to her side, as she stared blankly ahead. Her mind was only filled with the words that defined her very being.

"Do you know who I am now?" Kostas asked.

"You are my master, and I am your slut," Mercedes moaned. "I want you to play with my breasts. I want you to lick my nipples. I want your cock in between my breasts. I want your cock inside my pussy. I am your loyal slut and I will obey."

Kostas let out a bellowing laugh, pleased at how easy it was.

Every time I think my slaves have surprised me for the last time, they pull off something like this. For the first time in a while, Kostas thought about just how lucky he was to have ended up at the monastery. I knew the sluts here would be high quality, but I never thought they would be so…effective.

The enthusiasm with which sluts like Byleth and Manuela had for increasing his harem was inspiring. Just thinking about it was fueling his fire, and he was going to take it out on his lovely new addition.

"All right, let's see what else this bitch can do," Kostas said. Manuela had given Kostas a couple of commands for him to use. She said that they were trigger words she had implanted inside Mercedes's mind. When Kostas asked her about them, Manuela just winked at him and said that she didn't want to spoil the surprise.

"Manuela told me that you want to be naughty," Kostas said. Upon hearing the trigger word, Mercedes' eyes returned to normal, but instead of the usual kind expression she was known for, her eyes were seductive, filled with an intense desire. Mercedes wanted Kostas, and she wanted Kostas to want her in return.

"How about I give you a little peek?" Her voice was much deeper, much more sensuous than it had ever sounded before. Kostas had only talked to her for a few brief seconds, but even he could tell that her personality had changed entirely.

Mercedes took a few steps away from Kostas and began to undress. She started by slowly undoing the knot on her cloak, smiling sensuously as she took it off and dropped it to the ground. She did the same with the cloth around her neck, briefly biting it before she too discarded it. Her shirt and skirt were next, as she took her sweet time peeling off her blouse button by button. Kostas's cock grew more erect, as Mercedes discarded her uniform, showing what lied underneath.

Mercedes was now standing in the cathedral wearing black lace lingerie that left little for the imagination. Mercedes ran her hands through her hair, posing for Kostas and showing off all the right angles.

"You like what you see?" Mercedes asked with an alluring tone. While Mercedes was in her trance, Manuela had given her specific instructions to wear the lingerie for their Master and then placed it inside Mercedes' closet afterward. Until now, Mercedes was never even aware that she was wearing it.

Kostas was surprised to say the least, not expecting this level of eroticism from the pure-hearted Mercedes. The girl he had exchanged words with couldn't be more different from the girl seductively swaying her hips, presenting Kostas with a spectacular view of her ass.

Mercedes knew that Kostas was enjoying her performance which made her feel incredibly hot. Mercedes reveled in being Kostas's slut, her heat building as she craved for more of his attention. She felt in control proudly flaunting her body, even though that couldn't be further from the truth.

Mercedes turned back around and pulled on the straps of her panties. "Want more?" Mercedes asked. Kostas nodded with a stupid smile on his face. In response, Mercedes did away with her lingerie, revealing every single inch of her incredible body. Mercedes ran her hands up her body and cupped her naked breasts, displaying their beauty to her master.

"I hope my breasts are to your liking, Master. I know they'll feel sooo good around your cock," Mercedes said. She slowly massaged her full breasts, feeling her nipples harden.

"Oh really?" Kostas asked. Kostas walked forward and sat down on the front cathedral pew. "Well, why don't you come sit on my lap and we'll go down from there?"

Mercedes smiled and walked towards Kostas, her hips swaying with every step. She sat down on Kostas's lap, his cock rubbing against her pussy. Mercedes cupped her breasts again, offering them to Kostas. Kostas accepted and attacked her breasts with great enthusiasm.

He pushed her two perfect, supple breasts together and began to lick and kiss them. He vigorously licked her left nipple, rapidly moving his tongue up and down. He moved onto her right nipple and applied the same approach before going back. He went from nipple to nipple, breast to breast, as he thoroughly enjoyed their taste. Mercedes stroked her Master's head while he roughly sucked on her nipples, pleased that her breasts were bringing her Master so much joy.

In the heat of the moment, Kostas grabbed Mercedes by her hair and smashed his lips into hers. Kostas shoved his tongue into her mouth and Mercedes did the same in return. Mercedes moaned as she sucked on Kostas's tongue, savoring the taste of her Master. Once their lips separated, Kostas gave Mercedes's face a long lick, causing Mercedes to grow a wicked grin.

Mercedes got down on her knees and lowered Kostas's pants. She pushed her breasts onto Kostas's lap and wrapped them around his cock. Mercedes was quite aggressive, pumping her chest up and down at a rapid pace, as her need to please Kostas mixed with her own sexual desires pushed her forward. Kostas let out a satisfied groan which only made Mercedes happier. The warmth of his cock between her breasts was everything she had dreamed it would be, and when Kostas came, Mercedes considered it her sweet reward.

Warm bursts of cum showered onto Mercedes's face with plenty of it getting on her chest and her thick bundle of hair. Mercedes felt so naughty; she wished this moment could last forever.

"You liked that, didn't you? Hehe, you really are a naughty, little whore. Now, how about you get back up here and sit on my cock?"

Mercedes didn't need to think twice about it, as she got up and shoved his cock in between her creamy thighs. Mercedes wasted no time, as she began to vigorously bounce up and down on Kostas's cock. Each upward and downward movement on his cock brought her a crashing wave of pleasure. Her body was on fire; her Master's cock in her pussy bringing her intense pleasure.

Mercedes wanted this more than anything, and now that she had it, she couldn't get enough. Mercedes craved for more, as her mind and body filled with an insatiable thirst to be fucked by her Master. The rougher he fucked her, the better she felt. Every single sensation, every thrust, every touch, every lick upon her breasts. She cherished every second of it.

Mercedes smiled seductively down at Kostas and placed her hands on his chest. Kostas looked into Mercedes's eyes and saw nothing more than the **** need to fuck him. She was quite the sight to behold, naked with his cum all over her.

Manuela really did a number on this one.

"I love how horny you are," Kostas said. Mercedes's pleasure receptors got a jolt of electricity, as Kostas had used another one of her triggers. Mercedes's pleasure multiplied, causing her to let out loud moans.

"Hehehe, that's right. You spent all your time worshipping your goddess. What a load of horse shit. There is no higher calling. If anything, I am your god! Yes! All women like you are meant to worship me! To become my sluts, my whores! The princess, the professor, the knight! It didn't matter who they were before they met me! They were just more sexy sluts for me to take for myself! Just like you. Like the rest, you're horny for my cock. I'll fuck you as much as I want, HOWEVER I want, and you'll like it like the whore you are. You'll worship my cock for the rest of your life. You love being my horny slut."

Every time Kostas said her trigger word, Mercedes's pleasure continued to multiply. As a result, Mercedes's movements quickened, letting the feeling of his cock grinding inside her pussy fuel her. She wanted him to go even harder, to have every inch of his cock inside of her. Her head grew dizzy, the pleasure threatening to tear her apart, but she hung on, not wanting to miss a single moment. Her very being was becoming defined by a desire for her Master and his cock.

Mercedes was her Master's slut and she would do anything for him.

Kostas was thoroughly enjoying the girl becoming more and more slutty before his very eyes. He loved the way his crest transformed these girls, turning them into their best, most depraved versions of themselves. He was showing them who they truly were deep down, and in the end, they always thanked him for it.

"OHHHHHHH YES!!!" Mercedes yelled. "I LOVE YOUR COCK, MASTER! PLEASE MAKE ME YOURS! RAM YOUR COCK INSIDE ME!!! PLAY WITH MY BODY AS MUCH AS YOU WANT!!! FUCK ME, MASTER!!!!!!"

Manuela's programming along with Kostas's crest had fully reshaped her mind. Lust had taken hold of her, and following Manuela's plan, Mercedes was defenseless against it. Even as she serviced Kostas, more of Mercedes's former self was being erased and replaced by her new, slutty personality.

Deep in her subconscious, the kind, selfless girl that was known as the real Mercedes was still in there. The thing Manuela had been most afraid of was Mercedes's strong will and her capacity to stay true to her beliefs. If Mercedes's true self could somehow break free from Manuela's programming, she might be able to resist and save herself.

Sadly, that never happened.

Kostas came inside Mercedes, cementing the changes made to her mind. The last shreds of Mercedes were wiped away, replaced by a dirty girl whose only calling in life was to worship her Master and his cock. Her new tattoo made her even sexier than before, completing her new, slutty appearance and personality.

Kostas enjoyed the sight of Mercedes with his cum all over her. What made it hotter was how Mercedes was cleaning herself off, trying to swallow every drop of his thick semen. As his semen touched her tongue, she felt an irresistible desire for more. The heavenly taste along with the smooth, creamy feeling on her tongue was more than divine, and she wanted all of it.

"You love the taste of my cum, don't you slut?" Kostas said scoffingly.

"Yes, Master," Mercedes said. "It tastes so good. I need more. I'm your dirty slut Master. I'll do whatever you want."

"It really is the good girls that end up being the biggest whores," Kostas said.

Mercedes' naked body, his crest glowing above her wet pussy, the sweat causing her messy hair to cling to her skin, his cum all over her, and her wide, flirtatious smile; she was completely transformed from just a short while ago.

And Kostas vastly preferred her this way.

She was now much more fun. The girls of the Blue Lions looked like they had the potential to be unbelievably dirty sluts just like their professor.

Kostas buried his head into Mercedes's chest, playing with her supple breasts once more. Mercedes moaned, as Kostas gently nibbled on her nipples with his teeth. He roughly yanked her hair again and pulled her into another deep kiss.

Kostas would find another girl to play with soon, but Mercedes was simply too erotic to stop now.

He had to see just how true her devotion was.

Author's Note: Finally got this chapter done! Hope it was worth the wait! I think it came together very well!

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