Ilya was waiting for them anxiously when they arrived home. She threw herself on all three of them, wringing her hands and double checking to make sure that they were alright. She spent a rather long time verifying that Shirou hadn't sustained any injuries to his abdomen or biceps and eventually an exasperated Rin dragged her away under the guise of a hug, for which Shirou shot her a grateful smile.
Berserker was as stoic and silent as ever as Shirou animatedly described their escapades. Ilya was a gratifyingly rapt audience, gasping and squeaking in fright at all the right spots. Shirou cast Berserker as the hero of his tale, barely mentioning his own heroic leap from the window or his one sided fight against Archer. He glanced at Rin before he mentioned the file that she had taken as if asking if they should tell Ilya about it. Rin nodded.
"No more secrets. No more lies." She said.
Shirou nodded and continued his tale. But what was that in his eyes? Guilt? Rin knew that he wasn't telling her everything and she was beginning to form a theory about why.
When he mentioned Archer's master the mysterious blue haired magus Ilya's interest piqued.
"Blue hair? About my height, about your age?" She verified.
Rin was surprised.
"You know her?" She asked.
"Maybe." Ilya replied. "I think I saw her once several years ago when my father was meeting with a representative from the Matou family. Could she be the Matou heir? S- something. Sakura?"
"Matou heir?" Shirou asked, one eyebrow quirked in confusion.
Rin explained that most mage families sent their children to the Clocktower for some basic training before instructing them in family secrets. Being such a small and closely knit (if not exactly friendly) community means that most mages know each other, especially mages of an age to have attended the Clocktower together. The Matou family, even more secretive than the rest of the Mages Association, never sent their heirs to the Clocktower to train. Rin had heard rumors of an heir being groomed to take over the family but she had never met them. Until today, apparently.
"So Archer's master is here from the Matou family, you're here from the Tohsaka family, and Ilya's here from the Von Einsbern family, right? That's the three families mentioned in Genjo's letter as being connected to the Omega Weapon. That can't be mere coincidence?" Shirou said.
Rin tapped a thoughtful finger against her chin.
"Hmmm. Unlike me and Ilya this Matou girl obviously knows about her family's connection to Omega. I hadn't even heard about it until I came here. Perhaps we could track her down and force her to reveal...ugh. But this discussion is rather pointless." She said.
She waved the file that she and Shirou had stolen from the safehouse.
"I'll read this tonight, it looks like it's big enough to take a while to get through. It may answer all of our questions so it's pointless to ask them right now. I'll read this tonight, we should plan again in the morning." She said matter of factly.
Ilya protested but she was exhausted from the day's exertions. Caster left with her to tuck her into bed and make sure she didn't stay up to hear what Rin found in the file. Shirou nodded grimly, his curiosity about the file clearly gnawing at him, but left Rin to her work. Rin made her way into the study to begin her work, spreading the file out on a table near where Caster's magical map was situated. Berserker followed on her heels like a bulldog, silent and protective.
She had just spread the files out to begin reading when she caught sight of Shirou through the window lugging a heavy load towards the garage. Curious, she pushed herself up and opened up the shutters, rapping on the glass to get his attention before opening the window. He sauntered over and to Rin's surprise she saw that he was carrying the items that he had purchased at the music shop, two heavy industrial sized spools of piano wire.
"Where are you going with all that?" She asked.
Shirou grinned and leaned his elbows on the window sill, poking his head into the room and waving at Berserker.
"It's a secret!" He said. As if suddenly recalling Rin's words he changed his tone.
"Er, no more secrets. Right. You'll find out tomorrow, is what I meant to say."
"You're leaving right now?" She asked.
"Eh, life's too short to wait around, ya know?" He said.
Rin gave him a flat look that turned serious when she leaned in.
"Just...be careful." She said, concern heavy in her voice and a slight flush rising on her cheeks. She knew that she couldn't stop him from leaving on whatever foolish errand he had taken upon himself. Her suspicions about him were still in her mind but, more than that, she just didn't like the thought of him being hurt again.
Shirou looked pleased and, to Rin's great surprise, blushed a little bit himself.
"Oh! Thanks, I will." He said. The color in his face rose and his eyes darted around the room. His usually cheerful demeanor had changed into an aura of uncertainty.
"Look, ah, after all this is over, well that is if you aren't...er...maybe you and I...we could...um." He stammered, scratching at the back of his head nervously. His eyes darted around like a drowning man clutching for a raft.
"...yes?" Rin asked in a small voice, hoping against hope that he would continue.
The mood broke when Shirou's eyes fell on Berserker, however, and he seemed to deflate slightly.
"Er, never mind. Lemme know what you find in that file." He said disheartenedly, hoisting the two spools of wire once again and trudging towards the garage.
Rin drew her head back in through the window and slammed it shut, shooting a glare at Berserker even though he hadn't done anything wrong. She couldn't see him from behind his book but she thought he might have been smiling. Did he find Shirou amusing? Or was he glad that he was gone because of his feelings for Rin?
It was all very confusing. Rin marched back to her desk and began reading the file.
It was a string of security reports dated nearly ten years ago, presumably from the same facility that the medical reports she had glanced over came from. Although much of it had been censored with thick bars of black ink what remained was both illuminating and disheartening. There were a number of useful clues that Rin picked out. References to a change in security procedures for the elevators to the surface meant that the facility had to be underground somewhere. A casual mention of added security for packages delivered by the Valencia postal service meant that it was definitely here in the city.
Beyond that the report read like something you might find at an SS prison camp. There were reports of "subjects" being herded into containment areas and applause for security officers who ensured that none of them escaped. Routine reports of subjects being hauled off for experimentation and other procedures. Casual mentions of subjects being 'neutralized for noncompliance'. There were death counts, reports of incoming subjects being kidnapped for the Project, reports of bodies being discretely disposed of.
Rin felt sick that her family could have been involved with such a level of inhuman atrocities. She skipped ahead to find any clues about the physical nature of the Omega Weapon itself. To her surprise she was able to find quite a bit. She had somehow felt that the existence of the weapon was something that not even the report could reveal to her. She had assumed that the weapon was something like a magical sword, shield, or suit of armor. The file spoke of containment and testing procedures, transporting it in sealed capsules, its stimulus to biological and magical energy, and the Weapon itself being fed back into storage tanks when it wasn't in use. Could Omega be some sort of magically engineered biological weapon? Some ritual or implant?
A prickling suspicion needled at the back of Rin's mind but she pushed it away.
The last part of the file detailed how Omega had been stolen, the event that had sparked off the search she was now on. It was the only section of the report that the names hadn't been censored out of. There had been an attack on the underground facility by an old time enemy of the project head, a man named Emiya Kiritsugu. Emiya had been trying to bring down Omega since the beginning and the attack was his final stroke. He broke into the facility, killed most of the security forces, and stolen the Omega weapon. Rin's heart began to pound as she read on. He had also rescued a single test subject. Then he disappeared. The enforcers that the Omega project head Kotomine Kirei sent to track him down never returned.
Rin set the file down and stared into space, her face painted with shock. All of her suspicions came rushing in at once. Shirou's reticence about his past and his driving desire to take down Omega, his unbelievable powers that he hadn't even known were magically based until she told him, even his insistence on using a false name when they had first met. It all suddenly made sense. He was the test subject that had been rescued from Project Omega. And he wasn't looking for the Omega Weapon. He already had it.
Rin felt dizzy from the realization. She needed sleep, needed time to process what she'd learned. A glance out the window showed the first pale rays of dawn peeping through the curtains. She'd stayed up all night without realizing it. Berserker was still seated across the room, his chair leaned back and his feet propped on a desk, his mouth open slightly and soft snores coming from his rising and falling chest. She could see the contours of his face beneath the criss cross of scar tissue, his gnarled missing eye twisting an empty patch on his face.
Between her growing infatuation with Shirou and the hectic demands of the War it suddenly struck her how much she took him for granted. He was so silent. Stoic. Uncomplaining. It was difficult to tell what he was thinking or feeling, what his needs were. Did he have feelings for her? If so what were they? Was he still worried about who he was? If he was a good person? She could trace the details of his craggy features and Rin suddenly realized that she had stood and crossed the room, standing within arms reach of her mysterious partner.
His eye opened slowly. The feet of the chair came to rest against the ground but he didn't rise. He looked at her quizzically. Neither of them spoke as the moments stretched on. Even sitting he was nearly as big as she was. Rin reached out slowly to touch Berserker's face. Two fingers traced the line of his jaw, the slanting rays of the sun sending the shadow arcing over his neck and the outline of his collar bone. His skin was rough, leathery, textured by scar tissue. He leaned into Rin's fingers almost imperceptibly as if relishing her touch.
"Who are you?" She asked softly.
"I don't know." Berserker answered sadly, his eyes falling from her gaze.
She didn't know what had prompted the question but she immediately regretted it. She drew her fingers back a little too quickly, clasping them to her chest as she backpedaled away from the suddenly awkward silence.
"I'm sorry…I shouldn't have…" Rin stammered.
Berserker rose fluidly with his fighter's grace and crossed the room. Standing he towered above her as he always did. But as always his presence was like a bulwark, not a threat.
"It's okay." He said simply.
"Whoever, whatever I was before, I'm yours now." He said.
Rin's eyes widened but Berserker offered no further explanation to his words. She didn't know what to make of them. Was Berserker declaring his loyalty or...
Fortunately Rin was saved from having to come up with an answer by a loud knock coming from the front of the house. She quickly moved towards the study door, feeling Berserker's eyes on her back as she moved across the room. With an uncertain glance back at him she made her way to the front door, wondering who could be visiting at this hour. It turned out to be an elderly fellow in a postman's uniform. He had a single letter addressed to Ilya via express courier service. The postman bid Rin a good morning before handing over the letter and returning to his small delivery truck.
Rin absentmindedly placed the letter on the small table near the coat rack where she knew Ilya would find it, her thoughts preoccupied with what Berserker had meant. I'm yours now. It could be an affirmation of their contract. Or it could be a declaration of...something else. Rin's head was spinning but she was brought out of her reverie by the sound of footsteps on the stairs. It was the first and last person she wanted to see under the circumstances.
"I heard someone at the front door, didn't realize you were already up. You look beat, Rin. Are you up early or are you up late?" Shirou asked cheerfully, his happy mood defusing the situation. Rin glanced ove her shoulder and saw that Berserker standing in the doorway of the study. When he saw Shirou an unreadable expression came over his face and he turned to go back inside. Although he hadn't said anything she somehow instinctively knew that their conversation was over.
"What did you find out from that file? Does it tell us where Omega's main lab complex is?" Shirou continued, craning his neck over Rin's shoulder to glance at the files.
How much did he remember about the experiments? And how would he react towards her once he knew that she knew? Rin was afraid of things changing between them. For some reason she couldn't bring herself to reveal what she knew about him. Not yet.
"I...no. But there were some good leads. At least it will give us a place to start looking. It...it said...we should talk about what it said." She finished lamely. Shirou didn't notice what a hard time she was having.
"Good idea. C'mon you two, I've got something to show you." He said, making off towards the garage and motioning for her and Berserker to follow him.
Berserker fell into step behind Rin as Shirou lead the way to the garage. He didn't notice any of the tension that hung in the air between the three of them as he opened the door for Rin and then climbed into the car himself. Rin was mildly curious about where they were going, but she was more curious about how she was going to handle this new situation with Berserker and Shirou.