Disclaimer: I do not own the Fate or Tsukihime it belongs to Kinoko Nasu and Type-Moon.

Moonlit Fate

Prologue

Heavy footsteps thudded through the air as the priest made his way through the dilapidated old house, past rooms that had known better days and were now left to gather mold and dust, towards a locked and steel-reinforced door. The doorframe was also encased in steel, runes carved into the metal to further keep what was inside, inside.

The priest lifted the key from his pocket, fit it into the lock, and turned it to unlock the door. As it swung inwards, he raised his other hand, the gem it held flashing. The runes flashed in response, and with a sharp stink of copper let their vigilance down. The priest stepped inside, the gem in his hand dimly glowing and providing light as he made his way down old, dusty stairs to the basement below.

The house was located in the suburbs of the city, and had been purchased by his mentor ten years ago for the sake of the man's elder daughter. Although…calling it for 'her sake' would probably be pushing it. It wasn't a home after all. No one had ever lived in this house ever since Tokiomi Tohsaka had purchased it, and no laughter, no smiles, and no tears had ever graced it.

It was a prison, a place of convenience to lock away his greatest shame in the faint hope that somehow, in time, Rin Tohsaka could be saved of the curse that had been inflicted on her.

The man had died before he could find a way to save his daughter, and his student Kirei Kotomine had taken over the role of warden, making sure Rin Tohsaka was clean, feeding her with blood swiped from the blood bank…

…and making sure the chains which bound her were in good condition.

Today however…today was special.

Rin Tohsaka was slumped as usual on the floor, wrapped up in a straightjacket of consecrated cloth, black chains and a collar of thrice-forged, thrice-blessed meteoric iron binding her to the floor, the chains driven into the ground by blessed electrum stakes at forty-eight points around a circle of sealing. The magic of the seal expanded and grew with the prisoner, ensuring that it never needed to be taken off and replaced as she grew.

Ironic…considering vampires were supposed to be immortal and thus had no need to grow but then again, she was no ordinary vampire

Kirei's lips curled as he beheld the sight of the seventeen year-old vampire before him, the long dark hair falling to the ground the only part of her body exposed to him. Not that it really mattered seeing as the power of the seal paralyzed her completely.

How would her sister react should she learn of this darkest secret of her family?

With a smile on his face, Kirei knelt down and grabbed hold of one of the blessed electrum stakes.

Is it alright? Letting her go like this?

"It's better this way." Rin replied to the voice in her head. The voice had always been there, offering advice when she needed it, warning her if she was about to make a mistake, and even just listening to her when she wanted to say something but couldn't say it.

It was after all, just another part of her. It was what she would eventually become, the magus she was meant to be, but because she also wanted to be a normal little girl her magus-self had become detached from her, becoming a voice in the back of her head.

It was a little frightening at first, but she'd gotten used to it. As the voice said, it was a part of her, and so it wouldn't and couldn't do anything to hurt her. And it was helpful, helping her get past several problems in her magecraft that had stumped her on her own.

If anything, that proved that the voice was in fact her magus-self, held back by her own weakness. It had shamed Rin a bit, but the voice assured her that as a child, it was understandable that she was holding back. She should enjoy her childhood, short as it was.

Because once she grew up, then the fun and games would end, and she'd have all the power of her family's magic and the responsibility that came with it to deal with.

With that in mind, it hadwarned her that in time she'd have to make a choice: to be normal or be a magus. A magus had to place the Art above everything else after all, and Rin wondered if she could really do something like that, or what kind of choices she'd be asked to make.

And now she had an example.

As she watched from a window her sister being led away by hollow-eyed men in suits to a waiting car, the voice spoke to her. "How is it better this way?" it asked.

"Sakura cannot become a magus." Rin replied, parroting her father's words. "Only one in any generation can become a magus. Any more would risk unnecessary rivalry…"

"That's what your father said." The voice interrupted her thoughts. "What do you think?"

"M-me? I…"

"You won't just be a magus after all." The voice pointed out. "You'll also be the head of your family after your father. You have to place the Art above everything else, but you're also just a Human. You will grow old and die."

"What's your point?"

"My point is you need your family to carry on your legacy that is the Art."

"My father…our father knows best. I have to…"

"You're thinking like an ordinary person." The voice interrupted her again. "Think like a magus and look beneath the surface."

"I am!" Rin angrily thought back. "I know it's going to be hard for someone like Sakura. She…she's too timid…to be a magus. And she'll have to study another family's magic. That's even harder. But this way…this way she won't waste what talent she has…"

"Do you really think that's the end of it?" the voice asked. "Your sister is one year younger than you are. And don't deny it: those people look scary, don't they?"

"Well yes but…"

"Our sister is scared right now. Look at her. And she's going to have a hard time, without you or our mother to help her. Don't deny it: even with me, you still depend on mother and Sakura at times, don't you?"

Rin's thoughts fell silent, as she watched Sakura stop walking and look back at the house, at their father with a longing expression on her face. "Do you really think she'll thank us for it?" the voice asked.

"She will understand."

"Will she?" the voice asked. "Magi are Human too, and you know enough that plenty of magi allow their emotions to get the better of them."

"Sakura's not like that! She's a Tohsaka! We're better than that!"

"No, she's not a Tohsaka anymore. She's Sakura Matou now."

Rin felt her heart freeze over. Again, the voice was right. Sakura had the talent like her, but she didn't think like a magus. Well, neither did Rin completely the voice was proof of that but…Sakura. Things would be very hard for her…if she gained a grudge…

…would she really come back for revenge?

"You're smart enough to know the answer to that, my other self." The voice told her.

"What can we do?" Rin asked, watching and biting her lip as the hollow-eyed man in a suit began to pull a weakly-struggling Sakura along. "I can't just…and father…"

"Father is easy. We're supposed to be the next head of the family after all aren't we? Assertiveness will impress him."

"Well if you put it that way…"

"Hmm…do you mind if I borrow our body for a bit?"

"W-w-what?"

"Trust me…trust yourself…I'll get our sister back…and we'll impress father…"

"I…"

"Don't you trust me?"

Rin froze, indecision curdling her thoughts. And then she saw Sakura stumble, the other girl turning and crying for her mother, her sister, and their father, that she didn't want to go. Rin made her decision.

"I trust you."

"Thank you."

Fire ripped through her body at those words, Rin collapsing to her knees to her mother's concern as she began breathing hard. It was…terrible. Magic was painful, like hot metal being stabbed into you, but this…it was nothing like this. It was like each and every last one of her nerves was being stabbed with white-hot needles, her bones felt like they were being crushed by muscles as they tightened and contorted against her will…

"What are you doing?" she screamed in her mind. There was no answer, and she barely registered falling to the ground screaming and thrashing, her mother trying to calm her down. Through a haze of tears she saw her mother's terrified face and…and…and…

…thirsty…

She heard and felt blood pumping with every beat of her mother's heart.

…thirsty…

She could see the faint outline of blood vessels in her mother's neck, filled with rich, warm, healthy blood.

…thirsty…

She felt warmth with every touch of her mother's hands as she began to relax, catatonically staring up at her mother's face. Warm…warm…alive…

…thirsty…I'm so thirsty…

She could see and hear her mother trying to wake her up, a crimson haze blanketing her sight as hunger like nothing she'd ever felt before filled her. She dimly registered the burning in her body as her fingers contorted into claws, and her canines grew into fangs.

…thirsty…I'm so thirsty…I'M THIRSTY!

A second scream erupted from inside the house, and then another, and then another, each weaker than the last. The sound of Rin's screaming had frozen everyone outside, Sakura, the Matou henchmen, Tokiomi, Kirei, and even Zouken as he watched through an open car window.

Aoi Tohsaka's scream sent everyone moving.

"Mama!" Sakura shouted, struggling to run and forcing the man holding her arm to grab onto her shoulders and lift her off the ground. It would the last mistake he would ever make.

Glass shattered as a diminutive form burst out of the window, Kirei and Tokiomi jumping out of the way out of reflex as the small figure leapt across the intervening ground at blinding speed. The man barely had time to drop Sakura and show terror on his face before razor-sharp claws tore him to ribbons, blood and offal exploding around his killer.

Sakura screamed as she was drenched in blood, scampering away and running to her father. The other Matou henchmen rushed the little monster, only to meet the same fate. Again, everyone froze in horror as they beheld a blood and offal-covered Rin, her eyes burning red with fangs and claws bared as she stood over three bloody corpses.

"R-Rin?" Tokiomi stammered, holding his other daughter close as she cowered, holding tightly onto his leg. The girl turned her eyes to him, and his heart broke at the mindless hunger in those eyes.

How? How is this possible?

Ichor exploded weakly as Rin crushed an organ in her hand, the rich fluid washing over her face and into her mouth, and she licked the blood off of her hands. And then everything exploded into motion once more.

"Sakura," Tokiomi said, barely aware of the tears running down his face. Somehow…despite the apparent insanity and impossibility of such a thing…his eldest had become a vampire. He didn't how it had happened. It just did. "Get inside. Go to your mother."

Sakura didn't hesitate to obey, running for the house as Kirei rushed towards Rin, Black Keys flashing in his hands. Grinning maniacally, Rin charged inside of his guard with surprising speed and landing a kick on his belly.

Even with her newfound strength it was barely enough to stagger Kirei…but the shock of lightning that came with it forced him instinctively back. As he fell back, Tokiomi rushed forward, throwing a kick at his daughter's head. She dodged and attacked, fluidly swiping at him with her claws.

Tokiomi dodged the first two swipes, and caught the third on his arms. Reinforced cloth tore like wet paper, Tokiomi falling back and diving low as Rin launched another attack. Stepping behind her he threw another kick at her. She caught it on her arms but it was enough to send her flying a good distance.

Rin landed on her feet, snarling as swarms of Matou familiars surrounded her. Claws flashed as she cut hundreds of them down in one blindingly-fast motion, and then she was choking on her own blood as Kirei charged in, landing a crushing blow on her chest. The sound of his daughter's ribcage caving in was like a dagger in Tokiomi's heart, and he looked away, his face twisted in agony as he felt hot tears out of his eyes.

Rin flew back, landing on the opposite of the street and lying in a slowly-growing puddle of blood.

Kirei relaxed, and turned towards Tokiomi. Zouken approached slowly, only to freeze as Tokiomi turned icily at him. "Matou-san," he said.

Zouken sighed, disappointment showing on his face. With Rin Tohsaka now dead there was no way Tokiomi would honor their agreement over his younger daughter. And Zouken had such plans for her…

The old man opened his mouth, and then the three of them turned to the house as a scream rang out. "Sakura…!" Tokiomi shouted as he ran for the house. Kirei made to follow, but he'd barely taken two steps before the sound of tearing flesh drew him back. He turned just in time to see Rin spitting out blackish ichor.

"You taste disgusting!" she spat at Zouken's twitching corpse, her claws dripping with the old man's fluids. Then she turned to Kirei and smiled, her fangs showing as she flexed her claws. "You won't kill me that easily, priest!"

Kirei fell into his stance, Black Keys flashing into existence. Rin grinned, and then lunged at him with claws flashing with blood and sunlight. Kirei dodged at the last moment, an elbow coming down with a sound of breaking bone as he smashed Rin to the ground. Metal flashed and the vampire screamed and shouted in frustration as Kirei pinned her bodily to the ground with his Black Keys.

He considered using the Baptismal Sacrament then and there, but he hesitated and looked towards the house. His master would probably want to investigate this development, impossible as it was.

Or was it?

Moans filled the air, and Kirei glanced around him as dead Matou henchmen rose to their feet. Black Keys flashed into existence, and then the priest moved to purge the Dead rising from their graves.

Meanwhile Tokiomi Tohsaka rushed into his house, where he met a scene of utter horror.

Sakura was on the ground, screaming as she tried to keep her mother off of her. Aoi was pale, deathly so, her eyes blank and staring as she pawed at her daughter, her mouth bared-wide to bite and tear. A horrendous wound dripping with blood and bits and pieces of torn organs ran across her torso, clearly fatal…

…and clearly showing what she was now: Dead.

Bellowing with loss and rage, Tokiomi rushed forward, smashing his wife's living corpse away from their daughter and sending it flying across the room. It slammed against a wall and slid down to the ground, and then with a moan it rose once more and staggered towards him.

"Intensive Einascherung," he whispered, looking away as flames engulfed his wife's corpse. It didn't stop her, the Dead staggering forward even as her hair and clothes turned to ash, and her flesh melted and ran like wax. It only stopped when tendons and ligaments finally burned away as well, Aoi skeleton smoldering and smoking away on the carpet before them.

Neither father nor daughter cared. They huddled together, holding tight to each other. "Mama…onee-san…" Sakura whispered, covered in blood as she cried and held tight to her father.

Tokiomi didn't say anything, crying in silence as he held his only remaining daughter. Everything he had held dear, everything he had hoped for…

…it was all gone.

Why?

Why did this happen?

How could this have happened?

"What mockery is this?" Rin Tohsaka demanded. The priest usually just unsealed her mouth to feed her blood, and then sealed it again.

Tonight though, he had unsealed her entire face. "Rejoice…!" Kirei Kotomine said. "For I come bringing a wonderful gift: freedom!"

"You expect me to believe that?" Rin spat.

"True…" Kirei conceded. "…freedom must be earned. But I believe that you may yet earn it. After all as the Overseer of the Holy Grail War, it is my responsibility to determine those worthy of the Holy Grail."

"What?"

Kirei smiled as he pulled back his sleeve, exposing the large array of command spells on his arm. "Tell me," he said solemnly. "Michael Roa Valdamjong: what is it that you want most?"

A/N

Yes, SHIKI isn't Roa. Rin is.

Seeing as my focus is primarily on Different Fates updates will probably be long in the coming, though as stated in the profile, if I get flashes of inspiration I'll follow up on them. Which is basically what this work is, that is a flash of inspiration.

Not sure about pairings yet, but right now I'm leaning to love polygon with Shirou, Arc, Ciel, Sakura, and Saber. Any thoughts…?

Edited: May 28, 2017.