Fate Stay Night - Medea Caster route

Hi, I'm the author. 

Before you start reading this story/fanfiction I want to inform you that: 

1) This is my first time writing a fanfiction, so I ask you to have mercy on me if you don't like how I write or note some errors. 

2) I'm not English, if you notice any spelling mistakes I'm terribly sorry. 

3) I know that in the Nasuverse there are many terms for mana (Mana, Prana, Od) but I just limited myself to writing mana because I am a very lazy person. 

Other than that, I wish you a good read. 

One wanted to just live in peace, while the other wanted to just follow his ideal. 

None of them ever wanted to hurt or bother anyone, but fate had been cruel with them, since the very beginning. 

What would happen if these two people met? 

Once again she was alone. 

After killing her Master she teleported away from the burning laboratory, her already low reserve of mana now was almost empty and she knew that she didn't have much time left... soon she would die. 

She knew this sensation a bit too well: Hopelessness. 

The woman started to laugh weakly as she walked, she laughed because she realized that no matter what she did her fate would always be the same, that was her destiny, that was the destiny of the Witch Of Betrayal. But then at one point that laugh turned into a desperate lament. 

"Why it must always end like this?" She asked herself. "What have I done to deserve any of this!? I-I only wanted to live in peace, why did th-" 

Her thoughts were suddenly interrupted by a strong thunder, after a moment she looked up into the sky and felt the rain falling on her face. 

Only at that moment she realized that her robes were cold and heavy, she was soaked. When did it start to rain? 

How much time did she spend wandering in this forest? Minutes? Hours? She didn't know and she didn't care, it was too late for her anyway. Right in that moment of distraction as she walked she slipped on the slippery ground and she fell on the wet and cold terrain.

After a moment she was watching the cloudy sky, she didn't know if some drops of the rain fell into her eyes or if she was crying, the only thing that had her attention at that moment was a little star that she could see between the clouds in that dark sky. 

'This is the end, isn't it?' She thought. 'This is the fate of a witch, this is what I deserve for all the horrible things that I've do-' 

*crack* 

Once again her thought had been interrupted, but this time it had been the sound of a branch break to interrupt it. She slowly turned her head toward the place where she heard the sound and saw someone watching her... at that moment she felt something like relief, at least she wouldn't be let to die alone again. Even if she wanted to ask for help she didn't have enough forces to do it, the only thing she could do at that moment was to stay awake. 

After a second she saw the person she was watching sprinting incredibly fast towards her. She couldn't see very well because her sight was foggy, but once his person had gotten closer she noted that this person had red hairs. 

"Don't worry, I'm here." The person immediately said. 

As Caster realized that the person who had just spoken was a male she felt her body getting lifted. 

'He is running. She then thought. He was carrying her somewhere, but before she could think anything else she fainted.. 

That day Emiya Shirou was returning home from the Ryuudou temple after doing an errand for Issei at the temple, while he and the rest of the monk were on a pilgrimage. While he was returning home it started to rain, and he asked himself why he didn't bring an umbrella with him, but luckily no one would scold him when he would return home. 

But then at one point his thought had been Interrupted when he heard a strong thunder and shortly after that he heard a very strange sound, he could swear to himself that he heard a person speaking and then the sound of something falling. After turning around to investigate the strange sound his heart stopped, he saw a person wearing some strange robes on the ground looking at him. Before he could notice the blood or the strange magic smell the woman had he sprinted toward her, after reaching her he saw that the woman was in bad condition. 

"Don't worry, I'm here!" He said. 

As soon he posed his eyes on her he could see that the woman was soaked, very pale and she was even wounded on the stomach. Shirou didn't know the gravity of the wound, but he could see that she was not bleeding badly, maybe it was just a superficial cut. 

'There is no time to waste!' He thought Immediately. 

As he lifted her from the ground he noted that she was really light, he would have no problem carrying her, but he could also feel that she was more shocked than he first thought, and he could hear her breathing getting weaker. After a moment he started to run toward the nearest place where he could medicate her: the temple. 

Medea woke up in a soft and warm bed, and as soon she opened her eyes she could say that it was early in the morning, she was in good condition despite her head hurting a bit, and her mana reached stable levels... huh, she was still alive.

She could tell that nothing bad happened to her while she was unconscious, she could even say that she was treated with care... she was both confused and surprised at the same time. 

As soon she remembered what had happened the night before she started to think, who was the person that saved her? He was a magus, and a good one, no doubt about that. Somehow the man immediately managed to understand what she was and he refilled her mana to a decent level before she could disappear, he even managed to do it without forming a contract with her or doing strange rituals... Who was he? And why did he saved her? 

Medea had to understand what was the Intention of her "savior". 

Even if until that moment he had done nothing to her while she was sleeping in didn't mean that he had good intention towards her... but if he wanted to harm her in some way he would have already done it, maybe he wanted to control her, but he would at least try to restrain her in some way... not that he would be capable of doing it since she could easily dispel any kind of modern magic. Perhaps he was a magus that wanted to forge a contract with her? Could he be another master? Or Could it be that he was really just a passerby that managed to save her just by pure luck? 

She started to sense her surrounding, the first things that she noticed was that she was in a strong bounded field that worked against spiritual entities like hers, and at the same time she sensed that there was incredibly strong and dense magical energy in the air... she noted that it was the same energy that restored her reserve. After thinking a bit she concluded that she was in a well-defended territory connected to the leylines of Fujuki... yea, she had already studied the place, she was more than sure that right now she was at the Ryuudo temple. 

'Huh, how funny. She thought a bit amused. 

Her ex-master started the plan to betray her after she advised him to make this place their future base, the man was so foolish that he didn't realize the sheer number of advantages they would have if she managed to make this place hers, and right now she could only smirk. 

Yes, she was a Caster Servant, she was already one of the weakest class in direct combat and even now she wasn't in any good condition to fight anything, but now she was recovering her strength in a natural fortress, and she was specialized in territory creation, she started to feel lucky! 

After a bit, she started to think about the things that would soon happen. If her savior was just a normal person there was a good chance that he would start to ask her some question about who she was or what had happened to her, she could easily hypnotize him and make him forget about her, as a way to thank him she would not involve him with the war. If her savior was a magus that wanted to control her she could easily kill him or take control of him, and then she would take control of the temple, since she had all the energies she needed. If he wanted an alliance she would even accept it if he demonstrated to be a capable individual. 

She started to get up from the bed... and her blood immediately froze.. 

Right now the body she had was that of a Servant, the body of a Heroic Spirit, all of her senses had been amplified to inhuman levels... and right now she could tell that someone else was in the room. 

She quickly turned around and saw a boy sleeping on a chair. She observed him and she could see that he had red hair and he was a male, it was him, the person that saved her. 

...Why she didn't notice his presence earlier? Was she too distracted by her own thought? Or maybe the strong magical energy and the bounded field hid his presence from her before she recovered all of her senses?

After watching and analyzing him for about a minute she was sure the boy was some kind of magus, it was surprisingly difficult even for her, one of the best mage coming from the Age Of The Gods, to notice it. There were some meters of distance between them, and the boy had no trace of magic in him, she would have mistaken him for a normal boy if not for that strange and magical thing Inside of him. It was like he was hiding his magic from her... hiding? 

Her thoughts stopped. 'Wait... this modern magus was capable of hiding himself from me? Impossible!' She thought shocked. 'Only a Servant is capable of hiding from me, only... wait, could it be the ability of a Servant? An Assassin perhaps? Could it be that Assassin got summoned after I killed my master and I got rescued by Assassin's master? ... No, he can't be a master since he has no seals... But at first I couldn't sense his presence and his magic either, maybe he can even hide his connection to his Servant too?" 

As Medea thought she started to sweat cold, things had started to go in a bad direction. Just some moment ago she was confident about herself and she was already thinking on how to take control o the base, now she didn't know if there was an enemy nearby and from where the enemy would strike. After some moments she returned to study the boy, she hoped that she could sense something from him... but nothing, as if he was not even a magus. Even if she was not directly touching and analyzing him she should at least feel some kind of magic energy coming from him, but she sensed nothing... how was he capable of doing it? 

'Somehow the boy can hide the fact that he is a magus... maybe it's thanks to the thing inside of him? Maybe the same thing is hiding his connection to his servant? Could it be the Noble phantasm or ability of Assassin? It would be quite a useful skill to hide the fact that his Master is both a magus and a Master. She thought. She didn't know what kind of magic object resided in the boy's body, but the fact that she could sense a magic object on him confirmed to her that he was some kind of mage. 

She could sense her surroundings, and she could tell that no one else was in this room. The only kind of servant capable of hiding his presence was Assassin, and right now she wasn't sure that they were alone. If she started to absorb more energy to prepare herself for an imminent fight she would be struck down Immediately, maybe she could at least take the sleeping boy as a hostage... but was he really sleeping? 

...No, she had to talk to this boy... she now knew that if she did a wrong move it would've been her end... 

"Good morning." She said calmly, and after that moment she saw the boy jump from the chair. 

"G-Good morning!" The boy said as soon he woke up. Medea watched the boy getting a bit embarrassed, his surprise seemed genuine. "I-I'm sorry, I fell asleep here and... I-I hope that it didn't bother you." The boy said as he bowed down his head a bit. 

"...Don't worry, it didn't bother me, but now may I ask you some question?" She then asked politely. She didn't know if he was putting up an act or if he was genuine. 

"Sure... but first are feeling well? Does it hurts somewhere?" He asked concerned. 

"Yes, I'm fine, thanks for your concern, but were you the one who saved me? And if you are, why did you do it?" She asked. If the boy was really a Master it would have been more convenient to kill her, so why did he saved her? 

Shirou remained silent for a second, he did not expect the woman to ask him: 'Why did you do it?' That was a really silly question. 

"Yes I am the person who saved you, but let me ask you a question myself, why I shouldn't have saved you? Do I really need a reason to help someone who needs help?" 

"...You're right, I'm sorry for the foolish question, I hope it didn't offend you." Caster said bowing her head a little. 

'Huh, so that's how you want to play it, how sweet of you. Caster thought irritated. He could try to be a kind person as much he wanted, she would not fall for it, she was sure that he was a magus after all.

Shirou felt relieved that the woman was already in good condition and was already capable of moving and speaking without any kind of problem, but something else was on his mind now... 

At that moment he started to observe the woman and he could easily tell that she didn't trust him, there was something off in the way she was watching him... well, after all, he didn't know what the woman suffered or went through, so he could not blame her if she didn't trust the first person she saw. Shirou then remembered that the woman did have a little cut on her stomach, so she probably had been assaulted by someone. 

He saw it very well since... damn, how could he forget about that? Immediately after finding the woman he met on the way of the temple his teacher Kuzuki, the two of them returned together to the temple and immediately treated the woman's wound since his professor told him that it was nothing fatal. 

After a pair of minutes passed from when they had treated the simple cut the woman had started to breathe normally and her skin required color. After confirming that she was in stable conditions his teacher gave him some towels and a pair of pajamas, he then told him that he should have taken care of the woman and remain in the temple that night since he too was socked, in the meantime, he would call the head priest and inform him about the situation. After that Kuzuki turned around and went on his way, leaving Shirou alone with the woman. After some moments Shirou looked at the now hoodless woman and only at that moment he realized how beautiful she was... and now he was supposed to take off her clothes and dry her? 

After 15 minutes he managed to do the deed, but obviously, he was incredibly embarrassed. After changing her he took her to a room and put her strange decorative knife she had on a table. At first, after finding it in her robes Shirou could not help but stare at it for a pair of minutes, he even analyzed it and he could tell that it was... magical? He was not sure about it since after the analysis his head started spinning and he started to see a familiar land full of swords. 

As soon his head stopped spinning he went in the bathroom to change his wet clothes, maybe he had gotten a fever, so he had to change quickly. After changing he returned to the room where the woman was sleeping and he sat on a chair, that night he would remain there in case the woman woke up in the middle of the night, after some time he fell asleep. Strangely that night he didn't dream of the land full of swords, but he dreamt about a strangely familiar girl with purple hairs and pointy ears, her tragic story, and the horrible things she had done. 

As Shirou recalled the event Caster was watching him, she could tell that the boy was thinking something while looking away from her. 

'Is he thinking on what to say next or he is talking to his servant about the next course of actions. She thought. 

She was not too sure about it, maybe the theory that he was a Master was wrong and she was being too paranoid... but after some brief moment she thought: 'The leylines?' 

Assassins were very weak servants, they surely didn't need too much energy to sustain themself after all. Theoretically, If an Assassin was able to connect himself to them his master wouldn't have to support him, and that would explain to her why she could not feel any kind of connection with the boy... still, he did not have the command seals. Could it be that the magical object was hiding them? Could it be that this boy and the servant were working together while not being a master and a servant? Maybe the master of assassin was somewhere else, maybe he left the servant here so that he didn't need to sustain him? Could it be that even Assassin was a masterless servant? Why would he collaborate with this boy? Maybe something happened to its master and now Assassin was working with him? 

That would explain why he took her to this place, the boy already knew that the leylines at this point could sustain a masterless servant with no problem, and if he knew that she was the Caster Servant he knew that she would be weak against Assassins class servant if caught unprepared, and right now she was also in poor condition... Well, now that she thought about it she had more mana now than with her old master. 

She focused again on the boy, what kind of plan could he be preparing now?

'Should I ask if she wants breakfast? Yes! She now surely is hungry and we could talk while eating.' Shirou thought of a way to break the ice. 

"So, I know you may want to ask many things, but would you like to have breakfast first?" Shirou asked. 

'...Breakfast? What? Could it be that this is some kind of test to see if I'm reasonable? Or does he wants me to lower my guard? Should I accept? But it's not that I can refuse...' Caster thought. 

"...Sure, but-" She started to say. Before she could finish she suddenly sensed someone near the door, and then she heard someone knocking. 

"Emiya-kun, is the woman awake?" A man said from the other side of the door. 

"Sensel? Yes, she is awake and she said that she is fine." 

"Good, since that wound was barely a cut you should be more concerned about her mental health." The man said as he opened the door. 

The man opened the door and Medea almost flinched... there was no doubt in it, that man was an assassin! He was not a magus, but she could feel that he was a highly trained killer. 

'Could he be Assassin? No, I'm sure that he is a human...' Caster thought as she watched the man and falled to sense any kind of magical trace. 'But could he be someone controlled by Assassin?...Maybe, still, how did the boy just call him?' 

If she remembered well the word 'sensel' meant something like 'teacher'. Was the boy the student of an assassin? That man was an extremely good killer, she could hardly tell his presence... but only now, comparing the boy to that man, she noted that the boy had never tried to hide his presence. Maybe she really didn't sense him before because she was too distracted? 

Sure, she woke up in a well-defended magic territory, she didn't sense the boy because she was 'distracted', she 'jumped' to the conclusion that his ability to hide from her was the result of a Servant ability, she checked the boy and he had 'almost no trace of magic, and the man that he called 'teacher' was an assassin. This was just a big misunderstanding, all these things were 'coincidences' and she was being too paranoid. 

Jokes apart, right now she was sure that this boy was somehow involved with the war, even if he didn't have the full control of a Servant. But even if he wasn't a master she could not underestimate someone like him, it was clear that he was plotting something. 

The boy got up and walked toward the door, he watched the man and said: "Sensei, I asked her if she wanted to have breakfast and she said yes, while I go to change my clothes could you show her the dining-room?" He asked as he already started to think about what to make for breakfast. 

"Sure." The man simply said. 

After that the boy went on his way and only the 2 of them remained in the room, she didn't know what to say or do, but then the man said: "Follow me." 

And so she did, she followed the assassin expecting for something to happen, but he simply guided her to the dining-room and left her there. But before leaving he said in a neutral tone with no hostility: "Try to not cause problems." 

...Was he really controlled by someone? I didn't feel any kind of link and checked him for good, he is just a normal human. Medea thought. Things right now were very confusing, she had just met a boy that was a mage but had not magic traces, and with him, there was a professional assassin.

After a minute of waiting the boy arrived, he then asked her what she wanted for breakfast, but she simply said that she did not have any preference, after that the boy put on an apron and then started to cook. 

Well, It turned out that she underestimated him... or more specifically, his cooking skills. Just from the smell, she could say that her breakfast would be something good. Well, now she didn't care about the war, if these people wanted her dead she couldn't stop them, she was in the heart of the enemy territory, in front of her there was some kind of magus, then there was a professional human assassin around the temple, and she was pretty sure that somewhere behind her there was Assassin ready to cut her throat. There was no way that a weakened Caster could survive anything of the sort, so she just gave up and started to relax. In the meantime while she thought the boy served her breakfast and she started to eat. 

When she was princess Medea had been spoiled in every way possible, but she never ate anything of the sort before. This food was so simple, and yet it was more than delicious, she could tell that the boy had paid attention to all its details and flavors... she was so distracted that she almost forgot about the boy in front of her, just almost. Well, now that they were there to talk so he should at least confirm her suspects... 

"Why don't you let 'Him' eat with us?" She suddenly asked as she watched in the eyes the boy who was on the other side of the table. 

'Him? Oh, she meant Kuzuki-sensei?...Right, before I arrived he talked to me and he said that he didn't trust the woman, he said that for some reason she gave him some odd feeling... did she noticed?' Shirou thought. 

"Well, while coming here I asked him if he wanted to eat with us, but he said that he didn't want... to bother you." 

Medea sensed that the boy just said the truth. 

'Perfect.' She thought. 'There really is a servant here, I wasn't being too paranoid, now, what should I-' 

"By the way, I have not yet presented myself, I'm Emiya Shirou, It's a pleasure to meet you." The boy suddenly said while bowing his head. 

'Huh... Emiya Shirou... now that you said your name you are expecting me to say mine? Do I really have a choice now? Will you kill or attack me if I will not speak?...It seems that I have to relent.' Medea thought. Right now there was nothing else that she could do, she had to reveal her Identity. 

"I am... Medea." She said reluctantly after a moment. 

"Greece right? Just like I thought." The boy immediately said calmly. 

Medea wanted to scream 'WHAT?!' but before she could say it the boy continued. 

"You know, I could tell from your appearance that you..." He didn't finish the phrase after he saw Medea's shocked expression. 

'Why are you so shocked? It's obvious that you are a foreign, and your name only confirmed the fact. In fact, I already heard the name Medea... it was from that ancient Greek legend... I think. Shirou thought a bit confused by his sudden knowledge of Greek literature. 

Medea was the Witch Of Betrayal, she would know if someone was lying to her... but she could sense that the boy was speaking the truth.

'WHAT?! Just like you thought?! How could you even discover my identity in the first place?!' She stopped thinking for a second. '... Wait, why did he mention my appearance? Did my ears somehow reveal who I was? Maybe while I was unconscious he studied my body and he somehow discovered some signs about my Divine heritage? Maybe he even studied Rule Breaker? Yea... now I am sure about it, this boy is a capable individual, and he is way more dangerous than first I thought.' She thought as she carefully watched him. 

Shirou noticed the strange look the woman was giving him, maybe he said something wrong? He had to address the problem right now before it could cause further problems in the future. 

"I'm sorry Medea-san but I have to say it: it's clear that you don't trust me. I cannot blame you since I don't what you have been through, but I just want to put things clearly, now you are in a safe place, and from now on nothing bad will happen to you." Shirou spoke with a serious tone. 

'...Now I am in a safe place?" She thought. 

She wanted to burst laughing but she didn't, she was clearly in the lion's den but something was off... she sensed that he was telling the truth... Huh, it seemed that he never was hostile towards her, maybe he wanted to form an alliance since the beginning? 

That would explain why he never tried to restrain or harm her in any way, maybe he took her here in the hope that she would collaborate and help him fortify this place? Yea, that would not be a bad Idea, if she started to fortify this place the other Master and Servant pair would never come here since it would be suicide for them, and if ever one or more of those fools would try to assault this place they would get killed by the joint strength of her and assassin... It was a really good plan. 

But there was a problem, they should become allies, but now the boy knew that she was the Witch Of Betrayal and that she was already masterless... 

"Tell me Emiya-san, what do you want from me?" She asked as she watched him in the eyes. 

"I don't want anything from you, why do you ask? Ah, and just call me Shirou." He simply said. 

'...what?' Caster thought, now she was very confused. 

'Just look at her, she is clearly not used to kindness... Shirou thought bitterly as he watched the woman with a confused expression. What kind of life did she live until now? 

"I know that it can be difficult to believe, but I can only assure you that soon things will start to make sense. Now It's better that you finish your breakfast first then we can continue to talk." He then said. 

Medea nodded and then returned to eat, she had a lot to think about, but before she could start to eat she heard something strange... 

"SHIROOOOOOOU." 

"Fuji-nee?! Why she's here?" The boy said very shocked as he turned toward the sound. "...Oh, sorry I have to go, I will return soon." With that the boy suddenly got up and walked away. 

...Well, she was confused, the boy really wanted nothing from her. It seemed that the theory that he was working for another master was the correct one. Since she had now talked to the boy now she would like to speak to the Servant, she started to focus and she only sensed only 3 presences, and all of them were at the entrance of the temple, still, she couldn't sense Assassin presence, not that she expected the contrary.

"I know that you are here Assassin, could you at least make yourself visible so that we can speak face to face? We both know that now I have little chance against you." 

...

...

...

"Well I couldn't expect less from a cut-throats, but since 'your' Master seems distracted with other things I would like to talk about your future plans and the things you expect from me." 

...

...

...

'Did Assassin leave with the boy or he simply doesn't want to reveal himself?' Caster thought. 

She shrugged and returned to eat, she didn't know much about the boy but she could tell that he was an excellent cook, and this was just breakfast.