I do not own Fate/Stay Night or Freezing or any other series that might be referenced in this story.

AN:

Hi Raynare here. This is my first story so no flames please or if you have to keep it to a minimum. My heart can't handle it. :P This story was inspired by The Freezing Shinobi by Azure King and Azure Queen but using a different series for the crossover so you will see similarities in the 1st chapter but beyond that it should be different. Some of the terms are borrowed from other series such as the Dimensional Gap from Highschool DxD. The cover I used was found on and was submitted by SubaruSumeragi. I modified it a bit so that it looks similar to the character I had in mind. Anyways any helpful comments are welcome and I hope you enjoy this story.

"Talking"

'Thinking/Thoughts'

Freezing Magus Ch. 1

Standing before the Holy Grail was a sixteen year old boy with auburn hair. In his hands a sword whose beauty was immeasurable. To call it beautiful would only dirty it, yet it was only a copy. A copy which insulted the original, but the boy did not care, he was only focused on destroying the grail. He raised the blade over his head, and roared,

"EX-

CALIBUR!"

A blinding light came crashing down onto the grail and then the boy saw nothing.

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Dimensional Gap

". . . "He opened his eyes and saw swirls of colors all around him. He compared the scene to a kaleidoscope. "Where am I? Did I die?" The boy asked himself. "If I did then it isn't so bad, I destroyed the grail and was at least able to save her." He said thinking about the purple haired, kind hearted girl who he had sacrificed his ideals to save.

Then he heard a voice. "You're not dead yet Shirou onii-chan."

"Illya?!" Shirou yelled in shock, turning around he saw a petite girl with red eyes and snow white hair wearing a dress he considered immodest especially on such a young girl floating next to him.

"You're not dead onii-chan, at least not yet. Right now you are in a temporary bounded field I created inside the Dimensional Gap." Repeated Illya glancing at her brother, her brother who had sacrificed so much for a single girl. She didn't want to admit it, but she was jealous. Besides her parents, she never had anyone who showed so much love and loyalty towards her and then her onii-chan came and gave her a home. She felt loved again, but she wasn't loved as much as that Sakura which irked her.

"What do you mean? Why are you here? What happened after I destroyed the grail? Is everyone ok?" Shirou asked, shaking Illya.

"Calm down onii-chan. The Dimensional Gap is an area between dimensions. Kotomine is dead and so is Zouken so everyone should be fine. I followed you right as you fell through the gap created from the destruction of the grail." Explained Illya before frowning, pushing down her jealously. "But you're dying."

"Haaaa. So I am." He sighed looking very tired all of a sudden. It was bound to happen. He had after all projected Excalibur which was not meant to be copied. In doing so he had burnt out all of his circuits which led to his current situation.

"How can you be so calm about it?!" She cried with tears rolling down her face. "Why?! Why did it have to be you?!" 'Her otou-san and okaa-san were dead and her onii-chan was dying now. Was she destined to be alone?'

Shirou looked into the darkness before turning to her. "Because this is the path I chose and I don't regret it. It's ok Illya, I've accepted my fate already."

"NO! It's not ok!" Illya denied grabbing onto him. She didn't want to be alone, but she knew that both of them could not survive, so her brother shouldn't be the one to die. "Your body is dying, but I can give you another one using the Dress of Heaven, I can give you another body. My own body."

"No Illya don't waste your life on me!" Shirou yelled, pushing her away from him in an attempt to stop her.

"It's ok." Illya smiled sadly reaching out for him again. "You know, I can only live one more year because of my status as the lesser Holy Grail. My body wasn't made to last that long after the grail war because I was supposed to become the new grail. And even if I could live longer, without onii-chan, it isn't worth it. I would be useless to the Einzberns now that the grail is destroyed. So if I can give up my life for onii-chan, then at least there was some worth in it."

"But-"

"Onii-chan don't try to change my mind. I have already decided on it." Interrupted Illya. "But, there is something I need to tell you. Because we are currently between dimensions. So when you leave this place there is a high chance that you won't make it back to our world." She had held back some of the information she knew. While it is true that she could only live for another year, with Avalon she could live longer, but as long as he was alive it was fine. She knew that he would be devastated, but it didn't matter to her that he was in another world. She knew she was being selfish, but she wants her onii-chan to live.

". . ." 'This wasn't what he had wanted. She was supposed to live. This wasn't supposed to be happen to her. Why are the fates so cruel? She had just found family after years of loneliness and now she was going to sacrifice her life. Her life, she didn't have more than a year to live. How could they do that to her. She's just an innocent little girl even if she is technically older than him. No he can't accept this.'

"Let us get started then" said Illya taking his silence as acceptance. She proceeded to pushing her hand into Shirou's body and pulled out his soul along with Avalon and Archer's memories while simultaneously using her other hand to pull her own soul out of her body before pushing his soul, Avalon, and Archer's memories into her body.

"NO! I can't accept this!" He suddenly roared, and grabbing onto Illya and pulling her with him into the body causing them to fly back and fall out of the bounded field.

"BAKA ONII-CHAN!" Shrieked Illya before the both of them succumbed to the darkness.

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Mindscape

Illya woke up to a field of grass with a twilight sky full of gears and swords littered everywhere . . . Wait a sky with gears?! Illya jumped up, looking around and saw. "Onii-chan!" She cried, shaking the unconscious boy causing him to wake up.

"Uggghh, what happened?" He asked getting up while shaking his head trying to get rid of the drowsiness. The last thing he'd remembered was falling out of the bounded field and into the darkness.

Whacking Shirou's head Illya hollered. "Baka onii-chan! Look at what you've done. You forced the two of us into my body! Now there are two souls in one body and that isn't supposed to happen!"

"Ow! Ow! Ow!" He cried holding onto his head. "Sorry, Illya, but I couldn't just leave you." Then he noticed the twilight sky, swords, and floating gears. "Illya where are we?"

"I believe that right now we are in your soul. This looks like to Archer's reality marble." Illya answered with conflicting feelings inside her. She felt happy that her brother cared so much for her, but was angry at the idiotic stunt he'd pulled. She finally settle for glaring at him even if he meant well it was not a smart move.

Shirou looked away sheepishly, but then asked "But why are we here? And why are there differences from Archer's? We are the same person." As much as he hated they were in fact the same person.

"First we are here because only one soul can exist in a body, because there are two of us I believe that we are to decide here who stays and who dies. Second that's because the two of you had different experiences. Our souls are based on the experiences we had and felt in life which is reflected in the reality marble. I believe that the gears are a representation of the memories from Archer's arm that I took out of your body while the twilight sky and field of grass is your own soul. The weapons are the ones that you and Archer have remembered using your Structural Analysis and then are reconstructed in here." Illya replied already deciding on dying so that Shirou could live.

Suddenly a human sized oval shaped hole appeared distracting the two from their situation and prompting them to investigate which revealed that it was some sort of screen that allowed them to see the outside world.

Looking outside Shirou saw tiny hands and legs and screamed. "We're a baby!"

". . . Haaaaa. Only onii-chan's E rank luck could have gotten us into this situation." sighed Illya shaking her head. Then everything started shaking.

"What's happening?!" Cried out Shirou falling to the ground.

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Outside, Unknown Location

Illya and Shirou's intrusion into the world had been noticed by a woman sparking her curiosity causing her to investigate. This led her to discover a female baby with blood red eyes and snow white hair by the side of a road in the middle of nowhere. The woman was interested in the child who had come here the same way her kind did, so she picked her up.

The woman in question was a goddess in human form. She had long platinum blonde hair that fell down to her thighs with porcelain like skin and a large bust. She was wearing a sleeveless dark blue top with a long, light purple skirt that reached her ankles. Just looking at her took would take people's breaths away, but the most exotic thing about her were her yellow eyes with orange lines going through her pupils.

The woman carefully examined the child's body. After completing her inspection, she nodded and pressed her hand against the baby's chest causing blue lines to appear around their body. Unknown to her, this caused Shirou and Illya to start shaking and screaming in the pain making them collapse before it finally stopped.

While the blue lines were subsiding, the woman heard the sound of a truck coming down the road. Immediately she walked into the forest with the child and faded away.

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Unknown Facility

The mysterious woman phased back into existence holding the sleeping baby. She was then approached by a man looking between 40-50 years old. "Maria." Nodding towards her. "You know Chevalier will get suspicious if you simply wake up and leave." The man admonished before noticing the child in her arms. "Oh who do we have here?"

"Our new daughter, Emilya" replied now named Maria before setting down the baby and then walking away and fading away again, presumably returning to Chevalier.

The man walked towards child not looking phased at all at the declaration and picked her up. "So you're joining our family. You'll make a fine addition Emilya Aoi." Said the man smirking after looking over her with a calculative look in his eyes. "Well I'm your father Gengo Aoi and that reminds me, I have to introduce you to the rest of the family."

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Mindscape

Shirou looked over at Illya and asked. "Are you ok Illya and do you know what Maria did to us?" Shirou was really confused. Maria had done something to them and then declared that they were her child. While he was happy that they wouldn't die being left in the middle of nowhere, he was hesitant about calling that woman their mom. To him, Kiritsugu was their father and Irisviel was Illya's mother. He never had a mother so he was more accepting of it, but Illya had a complete family before so she might react badly to this.

Illya looked deep in thought and scanned the area. She did not like that these people were trying to take over her parents' position, but it would hopefully be good for her Onii-chan. Shirou had no idea what she was doing, but since she was more experienced than he was, he could only wait.

Finally Illya replied. "She changed our DNA. Biologically our body is now her child. Though the same can't be said for that man, Gengo. The thing is I don't know what my body is made up of now. Her DNA took over 80% of our body. So the 70% of magic circuits that I had are down to just 20%."

Shirou looked confused. "Why are you referring to your body as our body?"

Illya looked over with a deadpan expression. ". . . Is that all you got out of that onii-chan?"

"Ahahaha . . . sorry" Shirou apologized while scratching the back of his head. He noticed that she had avoided answering whether she was ok or not.

Illya pouted. "Moooe. Baka onii-chan. Still we need to solve our immediate problem before we can investigate what that woman did to us." Illya really wanted to investigate what that woman did to them but she knew that they had more important priorities.

"What problem?" He asked. There didn't seem like anything was wrong at the moment besides their situation.

"Well the fact that there are two souls in one body! Did you forget?!" Shouted Illya while hitting Shirou on the head. Her onii-chan can be really dumb sometimes.

"Ow! Ow! Ow! What's wrong with having two souls in one body?" Shirou asked rubbing his head. He really didn't get it. What's wrong with two souls in a body? Wouldn't it be like a split personality or something?

"BAKA! A body can't handle two souls. It will start deteriorating because it can't handle the strain of supporting the both of us. Only one of us can be here even with Avalon." Illya explained.

"Then remove me Illya. It's your body. You should be the one living not me." Shirou could not stand the fact that Illya was trying to give herself up to save him.

"No! The whole point was that I was going to save you and give you a new life! I'm not letting you die!" Rejected Illya. Why couldn't he see that she only wanted to live and be happy?

The siblings glared at each other for 5 minutes before Shirou relented and asked softly. ". . . So what happens now? I don't want you to die Illya."

"Onii-chan. . ." Whispered Illya while blushing. Even though he has a chance to live he still cares for others. He truly is the best brother a sister could have.

'. . . The only way for us to continue to live would be to merge our souls.' Illya thought, before blushing at her thought. 'Ah me and onii-chan together forever. Forever intertwined. Never to separate . . . Bad thoughts Illya, no don't think that . . . But to be with onii-chan for eternity.' Illya started shaking sided to side with her hands against her face.

"Illya are you ok?" Shirou asked, having no idea what was happening inside her head.

"Ah yea I'm fine onii-chan." Replied Illya, before she went on to explain her solution.

"There is one option, the process would combine our souls together so that we are one person, but if we do this we won't be us anymore. It will be a blend of the two of us. We will still have the memories from our current selves, but our personality will be fundamentally different. There will be qualities from the two of us, but basically we will be a new person." said Illya. 'It'll be like our child . . . No! Bad thoughts don't think about that . . . Still . . . Our child Ahhhhh.' Illya could not stop thinking about her and her onii-chan being together.

Hesitantly Shirou asked. "Is there no other way?" Shirou was willing to sacrifice himself to save Illya, but this solution, is it worth it? She won't be Illya anymore.

Shaking her head Illya answered. "This is the only solution we have right now. We don't have any way besides one of us dying. I'm willing to do this so that onii-chan has a chance." Shirou was Illya's only family left so she definitely won't him die.

After much thought he came to the same conclusion as Illya. She was his only family. Damn him if he didn't at least try to save her. ". . . Ok I'm willing to do this so that you have a chance. I've accomplished what I set out for even if I don't get to see the results or be with Sakura or Rin, at least I'm with you, my onee-chan." He said grabbing ahold of Illya's hands and pulling the two closer.

"Baka onii-chan." Illya replied, blushing while looking away. Even though her onii-chan is dense, he can still make girls around him swoon. "If we are going to do this then the assimilation will take a few years to complete, so while that happens we'll let our body's mind naturally develop which is where our base personality is going to come from."

Shirou nodded. "Ok let's do this."

"Ok onii-chan." Illya answered before pulling him closer to her. A bright orb appeared engulfing the siblings.