Prompt: Rin heard a loud groan when she woke up during the night and ran towards Shirou believing him to be in danger. Instead, she found a scene straight from her nightmares. Shirou was fucking her servant Queen Medb. And they wanted her to join them?

Tags: Shirou Emiya/Rin Tohsaka/Queen Medb, dubcon, threesome, rough sex

Rin tossed and turned in her sleep, a nightmare enrapturing her mind. For most of the day, today had been one of the best Rin had in years. She and Shirou had gone on a date to Shinto and it had been everything she dreamed of. They had gone on a date, and Shirou had seemed to finally enjoy himself. The Mall, to the glasses shop, to tea and lunch. And then there were the batting cages. Those had been the best. The look on Shirou's face every time she drove a pitch moving at 75 MPH, was hilarious. He honestly thought that just because she was a girl she couldn't hit. It was adorable. A day with just the two of them and Saber. It was perfect.

Then it wasn't.

Rin's heart plummeted as she watched the scene in her nightmare unfold. In the dim light of her mind's eye, she saw Shirou, his body a blur of motion, thrusting into Medb's welcoming heat. The latter's legs were wrapped tightly around his waist, her nails digging into his back as she urged him on, her moans a symphony of pleasure that seemed to echo through the confines of Rin's own psyche. It was a sight that made Rin's stomach twist into a knot of jealousy and anger, her cheeks flushing with a mix of embarrassment and arousal that she desperately wished she could shake off.

Shirou's eyes flickered in the direction of Rin, and his voice, cold and accusatory, pierced the silence. "This is all your fault," he growled, his movements not faltering for a beat. "If you hadn't been so jealous, Saber would still be here."

Rin wilted. Shirou was completely correct. It was her fault. She had wanted her date with Shirou to be perfect in every way... and part of that perfection was for Queen Medb to not be there. Her servant was insufferable. She was constantly bending over in front of Shirou to draw his eyes to her legs and she was even trying to sit on his lap at meals. She pushed his arm between her breasts too and constantly made jokes about riding Shirou to show she really was a Rider. Her servant knew of Rin's affection towards Shirou before even Rin learned of her feelings, and had taken pleasure in flaunting that by shoving herself at Shirou. The whore Queen wanted Shirou simply because Rin did. So Rin had refused to let Medb ruin their date and insisted that the Rider stay at home to "guard her workshop." It was a bullshit reason and they both knew it at the time, but Rider had accepted the assignment.

That had been a mistake, no matter how incredible her date with Shirou was without dealing with the headache that was Rider. Caster had ruined everything when they returned to Shirou's home to see a dagger held to Ms. Fujimura's neck. She had demanded that Shirou turn his command spells over to her or Fujimura would die. And the brave stupid boy had agreed to cut off his arm. Saber had tried to shield him, but it was a trap. The dagger of the Witch, "Rulebreaker" usurped control over Saber from Shirou. Their greatest and most powerful ally, a close friend, was now the servant of their enemy. A trap they only had to bait, because they didn't have a chance to fight back. Because Medb hadn't been there on Rin's orders.

The scene grew more intense as Medb threw her head back, her long pink hair fanning out like a curtain around her face, obscuring the twisted expression of ecstasy that Rin knew was there. Shirou's handsome features were contorted into a snarl of pure malice as he pounded into the Queen, each thrust punctuated by a harsh statement, "You're nothing but a jealous little girl, Rin. Your insecurity cost me my servant!"

The sound of their flesh slapping together grew louder, a cacophony that drowned out the cries of the real world. Rin's chest felt tight, her breaths coming in shallow gasps as she watched the man she cared for so deeply defiled her in the sanctity of her own mind. Medb's breasts bounced with every forceful pump, her nipples a stark contrast against her pale skin as they brushed against Shirou's chest.

"You're the worst," Shirou spat at Rin, his voice a harsh whisper that seemed to cut through the fabric of Rin's subconscious. "I hate you and never want to see you again."

The words stung like a slap across the face, jolting Rin awake. She sat up in bed, breathing heavily, her heart racing. The room was bathed in the soft glow of the moon outside her window, the silence thick and oppressive. But wait... there it was again. A low, pained groan, not from her nightmare, but from the room next door. "Shirou!" She exclaimed in a panic. Her heart in her throat, Rin threw off the covers and dashed to the door, her pajama shirt sticking to her damp skin.

The corridor was eerily still as she sprinted towards the sound, her mind racing with worst-case scenarios. What if he had re-aggravated his injuries? What if Caster had come back to finish him off? The thought of her failing him again sent a shiver down her spine, and she called out to her servant through their telepathic bond, "Rider! I need you to get to Shirou!" But there was only silence. No reassuring response, no witty remark. The lack of an answer was chilling.

Her hand found the doorknob, and with a swift turn, Rin shoved it open. The door flew open to reveal a scene that stole the breath from her lungs. There he was, Shirou, naked, sweat glistening on his skin as he lay on the bed, his face contorted in a grimace of pleasure and pain. He was not under attack, no it was worse. What stood out more than his exposed form was the woman straddling him, her pink hair cascading over her shoulders as she moved rhythmically, her hands on his chest, guiding him deeper into her.

"What the fuck are you doing?!" Rin's voice echoed through the room, her eyes wide with shock and betrayal. Rider, or rather Queen Medb, turned her head slightly, a smug smirk playing on her lips as she looked over her shoulder.

"I'm having sex with your precious Shirou, Master," she purred, her voice thick with satisfaction. "Would you like to join us? His cock will show you pleasure that you've never even imagined. He's quite talented for this being the first time he's been inside of a woman." The audacity was astonishing, it was a challenge thrown down in the face of Rin's horror.

Shirou looked up at her, his eyes glazed over with lust. "Rin..." He managed to get out between his teeth, his voice strained. "I didn't mean for this to happen." He was being entirely honest. He simply hadn't had the strength to fight back as wounded as he had gotten today, and she had been so insistent on taking advantage of that fact to finally claim him. And he did kind of want it… He had tried to resist, but when Rider offered to do everything in her power to get Saber back, Shirou had given into his lust, and let Rider have her way with him. He would not think about the fact that Rider was referring to Saber as his concubine. That was just her usual quirkiness.

Medb rolled her hips, grinding herself down onto Shirou's thick, pulsing member as she faced Rin, her golden eyes gleaming with mischief. The sound of their flesh slapping together filled the room, setting the rhythm for the tension that now thickened the air. Rin's eyes were glued to the scene, her chest heaving with a mix of anger and arousal. She couldn't believe what she was seeing, yet she couldn't tear her gaze away from the erotic display unfolding before her.

Rin pinched herself. She had to still be dreaming. This was so similar to her nightmare. She wasn't. All she could do was stare as Medb bounced up and down on that throbbing shaft. She licked her lips subconsciously.

Rin forced herself to glance away from their hips and over to the wall. It was one of the hardest battles of her life. "Of course, I'm not going to join you! Get a hold of yourself, Rider! And get the fuck off of Shirou!"

Medb giggled, her cheeks flushed with exertion. "Oh, come now, Rin. You know you want to. Watching can be fun, but participating is even better." She didn't miss a beat as she continued to bounce on Shirou's cock, her pussy clenching around him greedily. "But if you're too much of a prude to join, at least don't interrupt. It's ruining the mood."

Shirou's eyes found Rin's again, a silent apology in his gaze. Rin felt a mix of anger and sadness when she looked at them. "Rider," she said, her voice trembling. "I don't want this. Please, stop. You've made your point." She tried to ignore the warmth that was building in her core.

For a moment, Rin thought that Medb was actually going to listen to her, but the smug look on the Queen's face told a different story. With a dramatic flourish, Medb dismounted from Shirou's cock, the squelching sound of their separation echoing through the room. She sauntered over to Rin, her hips swaying with each step, her expression a blend of challenge and amusement.

"If you're not going to participate or leave, Master," Medb began, her voice a seductive purr that seemed to resonate through the very air, "then you might as well get a better view, like a proper cuck." Without waiting for a response, she bent over in front of Rin, arching her back and spreading her legs. "What are you waiting for, my knight? Come fuck me with that mighty cock of yours."

Rin couldn't help but gasp at the sight of Shirou's cock, standing tall and proud, glistening with Medb's juices. She had never seen one in person before, and the reality was both terrifying and fascinating. It was a thing of power, a symbol of masculine strength that she had only ever imagined in her most secret fantasies. Her cheeks flushed red as she stared, unable to tear her eyes away.

"You like what you see, Master?" Medb taunted, her voice dripping with honeyed malice as she looked at her Master, her desire-filled gaze locked onto Rin's. "You can join in if you want. Just say the word, and I'll let you have a turn with my prized stallion."

Shirou's eyes flickered with confusion and guilt as he looked at Rin, still unsure of what was happening. But when Rin didn't move, didn't speak, didn't do anything to stop them, he took it as a silent invitation. With a small sigh, he positioned himself behind Rider, aligning his cock with her soaking wet entrance. He wanted this, but more than that, he didn't want to hurt Rin. But... she wasn't saying anything anymore, just staring. Maybe Rider was right and Rin did just want to watch? The answer sounded hollow to Shirou, but he couldn't bring himself to care.

"Come on, Shirou," Medb urged, pushing her hips back to meet him. "Fuck me like the warrior I know you are." And with that, he thrust into her, filling her completely. Rin watched, her eyes glued to the spot where their bodies joined, as Medb threw her head back and moaned with pleasure. She had never seen such raw, unbridled passion before, and it was both terrifying and mesmerizing. Medb's breasts bounced with every thrust, her nipples hard and pink from the attention Shirou had been giving them.

The sound of their bodies slapping together grew louder and more rhythmic as Shirou picked up the pace, his hands gripping Medb's hips tightly. Rin's own pussy began to throb in response, her inexperience making the sight all the more intense. She felt a warmth spread through her body, a wetness between her legs that she had never felt before. It was wrong, she knew it was wrong, but she couldn't look away.

As the minutes ticked by, Medb's moans grew more frantic, her body tightening around Shirou's cock as she approached climax. Rin's breath caught in her throat as she watched the expression on Medb's face, a mix of pleasure and triumph. She had never seen such a look of pure satisfaction, and it was both fascinating and infuriating. Rin's eyes were drawn to the place where their bodies connected, the way Shirou's cock disappeared into Medb's pussy only to reappear, glistening with her juices. It was a sight that she shouldn't have been privy to, didn't want to be privy to, and yet here she was, unable to look away.

Medb's eyes snapped open, locking onto Rin's as she reached her peak. Her orgasm washed over her in waves, her body convulsing as she threw her head back and screamed Shirou's name. Rin felt a strange twinge in her own core, a feeling she had never experienced before, and she realized with a start that she was getting turned on by watching her servant with the man she had feelings for.

With a surprising amount of force, Rin pushed Shirou away from Medb, his cock slipping out of her with a wet pop. Medb looked at her with a somehow still smug smile, even after she had been forced to stop fucking Shirou. Rin's chest was heaving as she caught her breath.

Shirou looked at Rin, his eyes wide with confusion and lust. Before Rin could react, he grabbed her by the wrists and yanked her closer to him, his mouth crashing down on hers in a kiss that was both hungry and apologetic. She struggled for a moment, but his grip was firm, and the heat of his body was overwhelming. His tongue darted into her mouth, exploring every inch, and she found herself responding, her own tongue meeting his with a passion she didn't know she was capable of.

As they kissed, Medb took the opportunity to slide behind Rin, her hands deftly unbuttoning Rin's pajama top. Rin felt the fabric slide off her shoulders, exposing her naked breasts to the cool air. Medb's hands were everywhere, one gently cupping Rin's left breast, the other wrapping around Shirou's cock, which was still hard and pulsing with need. Rin's nipples tightened under Medb's touch, and she couldn't help but gasp into Shirou's mouth.

Medb's left hand slid down from Rin's breast to her stomach, her fingertips dancing over her mound, teasing her clit. Rin's legs began to tremble as the pleasure grew, her breathing becoming ragged. She didn't know how to process the sensation, the feeling of someone else's hands on her body, bringing her to the edge of ecstasy. Her eyes rolled back in her head, and she felt a sudden pressure in her core.

Medb chuckled into her ear, her breath hot and moist. "Looks like you're enjoying this more than you care to admit, Master." She pinched Rin's clit, sending a jolt of pleasure through her body, and Rin moaned into Shirou's mouth. Medb's fingers danced over her clit, and she felt the first stirrings of an orgasm she hadn't even realized was building.

"Look at how wet you are, Master," Medb whispered, her voice thick with lust. "You're so easy to please."

The words stung, but Rin couldn't deny the truth of them. She was close, so close, and they hadn't even really done anything. Her body was betraying her, responding to Medb's touch even as she felt guilty for enjoying it. But she couldn't stop it, couldn't hold back the wave of pleasure that washed over her as Medb's fingers worked their magic. With a cry that was muffled by Shirou's kiss, Rin came, her pussy spasming around Medb's digits.

Medb withdrew her hand with a wet sound, holding it up to show Rin the proof of her arousal. "See? You're already a mess, and you haven't even started to serve your man."

With a wicked smile, Medb stepped aside, gesturing to Shirou's cock. "On your knees, my Master. If you're going to be so selfish as to cum that quickly then you must be prepared to serve your new Master with your mouth."

Rin felt a mix of embarrassment and anger, but she couldn't fight the urge to obey. She sank to her knees, her eyes never leaving Shirou's. He looked at her with a hunger she had never seen before, his pupils blown wide with lust. She took his cock in her hand, feeling its warmth and weight, and she leaned in to kiss the tip. It was the first time she had ever done something like this, and she felt a strange thrill at the intimacy of it.

Medb watched with a knowing smirk as Rin took Shirou's cock into her mouth, her eyes half-lidded with pleasure. "That's it," she murmured, stroking Rin's hair. "Swirl your tongue around it, just like that."

Rin did as she was told, her tongue flicking and swirling around the head of Shirou's cock. She felt his hands in her hair, gently guiding her movements, and she took him deeper into her mouth. She had no idea what she was doing, but she was eager to learn, eager to make him feel good.

The taste of him was salty and musky, and she found herself getting lost in the sensation, her own arousal growing with each bob of her head. Shirou's breath hitched, and she knew she was doing something right. His hips began to rock, fucking her mouth with slow, shallow thrusts.

"Deeper," Medb coached, her voice low and demanding. "Take it all the way down."

Rin's eyes watered as she did her best to take Shirou's entire length, her throat tightening around him. She felt a strange pressure build in her chest, but she didn't pull away. Instead, she pushed through it, her cheeks hollowing as she took him all the way in.

Medb's hand came down hard on the back of her head, pushing her down further until she felt his cock hit the back of her throat. "Swallow," she ordered, her voice a dark purr. "Take all of him like a good little whore."

Rin's eyes widened with shock at the word, but she did as she was told, her throat muscles working to accommodate him. Shirou groaned above her, his hands tightening in her hair. She felt Medb's fingers dig into her scalp, guiding her movements, forcing her to take him deep.

"Look at you," Medb sneered, her voice thick with arousal. "You're a natural. I knew there was a reason I was summoned by you."

The taunts only spurred Rin on, and she began to bob her head faster, eager to prove herself better than the Queen. But it was the look on Shirou's face that truly motivated her. His eyes were closed, his mouth open in a silent cry of pleasure. He was lost in the moment, and she wanted to be the one to bring him back, to show him that she was more than Medb was.

As Rin's rhythm grew more confident, Shirou's breathing grew ragged. His hips began to buck, his cock sliding in and out of her mouth with increasing speed. She could feel his orgasm building, his cock swelling even more in her mouth.

"That's it," Medb coached, her voice dripping with satisfaction. "Make him cum like the good little slut you are."

Finally, with a roar, Shirou's hips bucked one last time, and Rin felt a hot flood fill her mouth. She had never experienced anything so intense, and she pulled back, unable to swallow the massive load. It spilled out, splattering her face and chest. She looked up at him, eyes wide and shocked, as his seed covered her features. Shirou looked down at her, his own eyes glazed over with pleasure, and she could see the regret in his gaze as he realized what he had done to her. That she might not have explicitly wanted it.

Medb, however, didn't miss a beat. She yanked Rin away from Shirou, and before Rin could even react, her mouth was on Rin's, licking and sucking the cum from her face. Rin's cheeks burned with embarrassment, but she couldn't deny the sensation was strange and oddly thrilling. Medb's tongue was warm and skilled, and she made sure not a single drop of Shirou's seed went to waste. It was as if she were claiming him, marking him as her own with every lick.

When Rin was clean, Medb stepped back, smirking. "You should be grateful, Master, you got a pleasure few women have ever had in my tongue." she said, her voice low and mocking. "I simply didn't want to see such a delicious treat go to waste."

Rin wiped her mouth with the back of her hand, glaring at Medb. "What the hell is wrong with you?" she snapped, her voice shaking with a mix of anger and arousal.

Medb's smirk grew wider. "It appears that this one still has some attitude, my knight. Break her on your cock!"

Shirou's eyes snapped open, and for a moment, Rin saw something different in them—a hunger that went beyond the haze of pleasure. He bent down, lifting Rin's limp form with ease. She felt his cock, still hard and slick from her mouth, press against her folds. He didn't ask permission, didn't seek her consent- she had already given it to him, whether he knew it or not- he simply picked her up, and pressed her back to his chest. His arms came to wrap around her legs, pulling them up and his hands rested behind her head, holding her in a full nelson.

In a swift, powerful move, he thrust into her, filling her completely in one go. Rin's eyes rolled back in her head as she screamed, the pain unlike anything she had ever felt. But as the initial shock wore off, she found herself lost in the sensation, her body already writhing with pleasure despite her mind's protests. She was so tight around him, so warm and wet, and she could feel every inch of him as he pulled back and thrust in again.

Shirou's hips moved in a steady, punishing rhythm, his cock plunging deep into her with each stroke. Her body bounced in his arms as he fucked her, her breasts jiggling with the force of his thrusts. The feeling was overwhelming, and she could feel her orgasm building with each passing second. She had never felt so full, so alive. It was as if she were being torn apart and remade with every plunge of his cock.

Medb watched with a twisted smile, her hand idly playing with her own clit as she enjoyed the show. "Look at her, my knight," she said, her voice dripping with malice. "My little master is nothing but a toy for your glorious cock now."

Rin's mind was a haze of pleasure and pain, her thoughts a jumble of confusion and desire. She didn't know who she was anymore, only that she needed more of what he was giving her. She writhed in his arms, trying to push back against him, to take him deeper. She had never felt so alive, so alive and so utterly consumed by another person.

Her nails dug into his arms as Rin's body was consumed by the relentless waves of pleasure crashing into her. Each time Shirou's cock hit her G-spot, she felt her sanity slipping away, replaced by an animalistic need for more. Her moans grew louder, echoing through the room, mixing with the slap of skin on skin and the grunts of Shirou's exertion. The sensation was unlike anything she had ever felt before, and she knew she would never be the same again.

Medb watched with rapt attention, her own hand moving faster between her legs as she felt her own climax approaching. "That's it," she whispered, her eyes never leaving the intimate dance between her Master and her lover. "Make her cum for you. Show her who she truly belongs to."

Shirou's strokes grew more powerful, more precise, as if he could feel Rin's body begging for release. Rin's eyes rolled back in her head, her mouth open in a silent scream as her orgasm ripped through her. Her body convulsed, her muscles clamping down around him, and she lost all sense of time and place. All she knew was the feeling of Shirou inside her, claiming her in a way she never knew was possible.

Finally, her body could take no more, and she slumped forward, unconscious from the sheer intensity of the pleasure. Shirou's thrusts slowed, his grip on her loosening, but he didn't stop. He pulled out of her, his cock still rock hard, glistening with her juices, and turned to face Medb. The look in his eyes was one of fierce determination, as if he had made a silent vow to conquer her as well.

Medb looked at him with a mix of awe and hunger, her own body begging for release. "That concubine couldn't even get her master to cum in her virgin cunt? Honestly pathetic."

Shirou took a step towards her. "Don't insult Rin!" he growled a warning.

Medb smirked, unfazed. She spread her legs wider, exposing her glistening cunt. "Your cock seems to disagree," she quipped, her hand stroking her folds. "You want more, don't you? Take me, my knight. Make me scream."

With a roar of his own, Shirou pounced on her, pinning her against the bed with his body. He took her legs and pushed them up, her ankles resting on his shoulders, a position known as a mating press. He thrust into her, filling her completely, making her eyes widen with surprise and pleasure. Her moans were immediate and loud, her back arching as she took his full length.

"Oh, Shirou, yes! Fuck me like you own me!" she screamed, her eyes rolling back. Her hands clutched at the bedsheets, her nails digging into the fabric. Her breasts bounced with every thrust, and she watched as Rin lay there, unconscious from the intense pleasure she had just experienced.

Shirou's strokes were punishing, each one hitting her G-spot with precision. Medb's eyes glazed over, her mouth open in a silent scream as orgasm after orgasm crashed through her. Her cries grew more feral, her body writhing and bucking beneath him. She wrapped her arms around his neck, pulling him in for a kiss that was more of a bite than anything else.

"Oh, Shirou," she moaned into his mouth, "You're so good. So much better than most other men." Her words were a blend of praise and challenge, pushing him to go harder, deeper.

He didn't disappoint. Shirou's pace didn't falter, his hips moving in a relentless rhythm that had Medb begging for more. Her legs tightened around him, her heels digging into his back as she tried to get even closer. Her pussy was soaking wet, and the sounds of their bodies slapping together filled the room.

"Harder," she demanded, her voice a mix of pleasure and pain. "Harder, my love!"

Shirou's eyes never left hers, his gaze intense as he obeyed her command. His hips slammed into her with increasing force, each thrust sending shockwaves through her body. She threw her head back, her hair cascading over the pillows as she screamed out his name, her body trembling with the power of her climaxes.

"Yes, yes," she panted, her eyes fluttering shut. "This is what I want. You, filling me up, making me yours."

Shirou's breath was hot against her neck as he kissed and bit her, his hands gripping her hips tightly. He was lost in the moment, in the feeling of her tight pussy around his cock. And as he felt her orgasm again, he couldn't hold back anymore. He came deep inside her, filling her with his seed.

Medb's eyes snapped open, a wild, triumphant look in them. "MINE," she whispered in his ear.

Shirou pulled out, his cock still hard, and looked down at her. "Rin is my girlfriend," he said firmly, his voice filled with a newfound authority. Medb was pretty sure that was a new development, and not one that Rin was aware of.

Medb rolled her eyes. "Fine," she said, her voice filled with a purr. "But you are still my consort and will fuck me whenever I demand it." Shirou didn't have the willpower to disagree with that demand.

Rin slowly regained consciousness, her mind foggy and her body feeling both sore and oddly alive. The room was dimly lit, and she could feel the stickiness of cum on her face. As her eyes adjusted to the light, she saw a sight that she never could have prepared herself for. Medb, or Rider as she was known in this bizarre situation, was kneeling before Shirou, her voluptuous breasts enveloping his still-erect cock, her mouth poised just above it, ready to take him back in.

Shirou's face was a mask of concentration as he watched Medb's every move, his hips rising to meet her mouth. Rin felt a twinge of jealousy as she took in the sight of Medb's large breasts. They were so much bigger than hers, and the way they could wrap around Shirou's cock was mesmerizing. It was as if Medb had been crafted to pleasure him in ways Rin never could.

Medb pulled away from Shirou's cock with a wet pop, looking at Rin with a smug smile. "Looks like you're back, my Master," she said, her golden eyes gleaming. "I hope you're ready to serve your master properly."

Rin's cheeks flushed with embarrassment, but she couldn't deny the strange thrill that shot through her at the word 'master'. She was the Master of Medb, but Medb was not wrong when she claimed that Shirou was her master. Medb's words cut through the air like a knife, and before Rin could protest, she found herself on her knees, moving closer to Shirou's body.

"Lick it," Medb instructed, her voice firm and demanding. "Lick Shirou's asshole like the butt slut you are."

The words were a slap in the face, but Rin couldn't ignore the pulsing need between her legs. She leaned in, her tongue tentatively touching the tight ring of muscle. The taste was faintly salty, a mix of sweat and arousal. As she began to lick, she felt a strange sense of empowerment, a thrill that she had never experienced before. She was doing something so taboo, so outside of her comfort zone, and she was doing it for Shirou.

Shirou's body tensed, and she could feel his muscles tighten as she pleasured him. His breathing grew heavier, and he let out a low moan that seemed to resonate through her very core. She just knew that Medb's eyes were watching with a mix of amusement and challenge. Rin knew that she was being used, that Medb was the one orchestrating this entire encounter, but she couldn't help but feel a twisted sense of satisfaction in being able to bring Shirou pleasure.

Medb threw her head back, her eyes closed in pleasure as Shirou's cock slid back and forth between her tits. His strokes grew more erratic, his breathing more ragged. And then, with a final groan, he came, his hot cum spurting out and coating Medb's breasts.

Rin's eyes widened, and she felt a strange mix of arousal and shock. Medb bent over and crawled towards her. "Now, my dear Master," she said, her voice low and seductive, "it's your turn to clean up my mess."

With a sense of determination that surprised even herself, Rin leaned forward and began to lick the cum from Medb's tits. The salty taste filled her mouth, and she couldn't help but feel a strange sense of belonging, of being part of something so primal and raw. As she did, she watched as Shirou positioned himself behind Medb, his cock still hard and ready for more. His cock probed at her asshole and the whore queen thrust her hips back towards him.

"Now, my love," Medb purred, "Fuck me like the king I know you are."

Shirou didn't hesitate, pushing into her tight, puckered hole with a force that made Medb's eyes roll back in her head. She moaned, her voice a mix of pleasure and pain, as he began to pump into her. Rin couldn't tear her eyes away from the sight of Medb's face contorted in ecstasy, her mouth open in a silent scream.

"You see, Rin," Medb managed to gasp out between moans, "I may be your servant, but that does not change the fact that I am your Queen."

The room was filled with the sounds of flesh slapping against flesh, of Shirou's grunts and Medb's cries of pleasure. Rin's eyes locked onto the spot where their bodies connected, the sight of his cock disappearing into her tight hole making her own pussy throb with need. She reached down and began to play with herself, her fingers slipping easily through her wetness.

Medb's body rocked back and forth, her tits bouncing with every thrust. Rin couldn't help but lean in closer, taking one of the pink, stiff nipples into her mouth and sucking gently. The taste of Shirou's cum on her tongue was surprisingly addictive, and she found herself eager for more. Medb's moans grew louder, and she began to buck her hips back, taking Shirou deeper inside her.

"Your boyfriend fucks me so good!"

Rin stopped her ministrations, paralyzing at that declaration for a moment. Boyfriend? They weren't dating? They were just friends… friends who had sex… and a friend who she was in love with. And a friend who at least cared for her. Maybe they should be dating…? She watched as Shirou thrust into Medb with such force that her entire body shook. Maybe she should take a page from her servant's book and just inform Shirou that they were dating now. It worked for Rider…

As Rin watched, she realized that this was not what she had envisioned when she had summoned Medb as her servant. The idea of sharing Shirou with her, of being part of such an intimate, depraved act, was something she never would have considered before. But here she was, kneeling before them both, her own hand buried between her legs, and she couldn't help but feel a strange sense of belonging. Her feelings towards Shirou had always been complicated, but she had never imagined it would evolve into something so... intense.

Medb looked down at her, her eyes glazed over with lust. "Fuck, Master," she panted, "You're such a good little slut for letting your Queen use your man like this. His cock feels so good!"

Rin felt a jolt of anger at Medb's words, but she couldn't deny the truth of them. Shirou was not just her friend anymore; he was something more, something she had never allowed herself to admit. Her boyfriend and her master. And here he was, fucking Medb in front of her, and she was doing nothing to stop it. Instead, she was getting off on it, her hand moving faster and faster as she watched his cock stretch Medb's ass. Yes, this is not what Rin had imagined before the Grail War, but she wouldn't change a thing if given the chance.

A/N:Rin became a bit more of a cuck than I intended whoops. Sucks because I have another Rin cuck one in development and I think some of the idea bleed over into here. I probably shouldn't work on two stories with such similar casts simultaneously again.

The timing of the story was simply because I needed Saber to not interfere, so bladeworks post-date with Medea interference worked. Nightmare was me trying to find a way to give the exposition without just doing a dump. It didn't work at all.

Medb is hot, but I think she's much more straight than this- the bi thing for her in this is mostly just a power dynamic thing. She gets off on having another woman below her in that sort of cuck position and uses her body to flaunt it- especially when Rin is bi which makes it easier for Medb. Medb is not really in love with Shirou, he's just one of her best lovers, and she calls lots of men my love.

These are definitely 2D versions of all the characters, but there are at least enough similarities to recognize them for slightly more than names and appearances. So yay I guess.

And leave more prompts below with any ideas you have as always. I will always be open to having more to choose from in the future.