Chapter 2 / The Differentiation Formula, Part 5

The clock struck twelve.

The moonlight flooded through Ikaruga's window without much fanfare as she closed her textbook and powered down her laptop. The time it took for her to accompany Murasame was about the same amount of time it would have taken if she had done the traps inspection, but she still found herself slacking behind her usual rate. It wasn't as if she was feeling lazy or tired. It was because of the investigation that caused her to dwindle in her thoughts irrelevant to her studies. Once she realized her inefficiency, she knew she couldn't continue on like that, so she stopped.

Ikaruga left her room, wanting to grab a glass of water before she headed to sleep, but along the way, she noticed a strange sight. It was almost as if the world had been reading her mind.

"Isayuki? What are you doing in front of my brother's room?"

The long-haired boy flinched, not noticing her approach. He had been standing upright, nodding off every so often. His energy was noticeably missing, but he tried to keep his usual upbeat tone as he turned to Ikaruga. "O-Oh, Ikaruga? What brings you here?"

"I should be asking you that question."

Isayuki proudly nested his hands on his hips. "I'm helping out Mister Murasame!"

Ikaruga blinked slowly. "In what way?"

"Mister Murasame went to his room after we returned, but he looked like he had a lot on his mind. I could at least tell that he was going to be busy, so I wanted to help. Mister Murasame then told me that if I wanted to help, I should stand guard outside here and make sure that no one interrupts his focus."

That would have meant that Isayuki had been staying here for the last few hours.

"You should head back to your room for some rest."

"I have to stand guard! I told Mister Murasame I could do—"

A big yawn escaped Isayuki's lips, causing him to be flustered.

"You're tired, Isayuki. It'll be fine. My brother will understand."

"Are you sure?"

Ikaruga smiled softly. "If you're uneasy, then I'll take your role for you. That way, my brother won't be disturbed by anyone else in the building and you'll get the chance to rest."

"You'll do that?" Isayuki gasped. "Wow, thanks! I appreciate it, Ikaruga!"

Isayuki stretched his arms upwards, letting his yawns out more freely. He gave Ikaruga a brief wave, wishing her a good night as he quickly left for his room. Ikaruga gently waved back until Isayuki turned the corner, prompting her to stop afterwards, but she remained still for a brief moment.

"Amnesia, huh?"

She turned towards the door and knocked. She might have promised Isayuki that Murasame wouldn't be disturbed by anyone else, but by the nature of her wording, it didn't include either Isayuki or herself in that act. She hadn't been a big fan of lying, but she was willing to teeter the edge by laying out a technicality. Honestly, it might have been in the Houou blood to do so.

"Murasame? Are you awake?"

There wasn't any response, so she welcomed herself in. Murasame barely ever locked his room to begin with, so if anyone really wanted to come talk to him, they were always able to do so. None of the staff would ever dare to if not strictly permitted by Murasame himself, nor their parents did so, since they were frequently out of the house and were physically unable to. By those means, Ikaruga technically had that right to enter like this all to herself.

"Murasame?"

The room itself was dark, but blue light was centralized around the corner where Murasame's desk was. She could see the outline of her brother hunching over the monitor of his computer. Lines of text covered his screen with its image reflected into his eyes. The only movements were from his hands, to control his mouse and his keyboard. Other than that, it was as if he was a statue.

Murasame was inept as a shinobi, but when it came to his work, he was the best of the best. Researching was a part of his daily task, whether that would be on the current market or his competitors, Murasame didn't let a single thing slip through the cracks. He never really thought about it too much, being rather dismissive about his skills in this particular field, but the focus in his eyes told anyone that they need to know about how good he is at gathering information.

"Murasame."

She called out once more, this time without the barrier of the door. Sometimes when he does do research though, he would get lost in the reports and documents, losing track of time easily , especially if it is on his own personal time where there wasn't any schedule to adhere to.

Murasame grunted without looking over. "Do you want something, Sister?"

"Sorry. I don't mean to disturb you."

"You're already doing that, so you might as well get whatever you want over with."

"I probably know the answer to this already, but I'm assuming you haven't done the inspection of the manor's traps yet. From the sounds of it, it would appear that you've been here this entire time."

"How would you even know that?"

"You forgot about leaving Isayuki at your door, haven't you?"

"The kid? Oh, shit! The kid!" Murasame spun in his chair in his own realization before coughing and recollecting himself. "I-I mean, of course not. How could something like that ever slip my mind!?"

Ikaruga sighed, deciding that it wasn't worth pursuing after that case.

"On a related topic, have you found anything interesting or worthwhile in the information you collected? As a reminder, it would be a good idea to relay any of it to the shinobi council for them to investigate further into it. If Dōgen had any involvement in this matter, then it is for certain that they will bring this up to a high priority. Who knows what might be left from his schemes?"

"Is that right? Was he hard to get rid of or something?"

"Dōgen was initially believed to have died during the original destruction of Hebijo Academy, but he was able to survive despite his fatal injuries. And then he made one more return to Hebijo to continue his conquest for world domination. You could imagine my friend's surprise, along with her squadmates, when he showed up for a third time in Kyoto. It's unlikely that he survived that final encounter, but considering his track record, one can never be too sure. We never did find his body, but that could be attributed to his amalgamation with Orochi."

"Orochi? That one yōma? That was in Kyoto too?" Murasame furrowed his brow from the familiar name. "Ah, never mind. I don't care that much, but the guy sounds like a real cockroach. If the guy is dead, he can stay dead. I don't need any more problems on my plate when I throw this operation of theirs into the shitter."

Murasame leered over to his computer screen.

"So far, I haven't found anything that I could deem as too important. Dōgen would have argued otherwise if he were here, but I think it's just a bunch of bullshit. None of the original research topics are tucked away in his data, so I haven't been able to figure out the process of what they're doing. However, there has been something that was bothering me about his journal entries."

"And that would be…?"

Murasame narrowed his eyes. "He mentioned a central experiment between all of the directors. Not only does this operation hold various ways that they would use these monsters, but they have something spawning from the middle of their collaboration."

He briefly touched upon the details Ikaruga needed to understand what he was saying, but the most important part of this was that the masked person had lied to him. When they said that the directors didn't even know each other, it contradicted whatever Dōgen wrote down.

If Murasame had truly taken that deal from the masked man, there would have been countless lies woven in that masked man's words from that point onwards. There was the possibility that he would have been withholding the truth until Murasame was confirmed to be joining them, but from the sound of his surprise of Murasame's rejection, the masked man probably thought he was already a lock-in for replacing their dead director. In other words, he would have been manipulated and if he had to hate something more than being looked down upon, it was being treated like a tool for somebody.

"No specific names though, so we got nothing to go off on from that end."

"There's something even bigger than the yōma that showed up at the facility?"

"If you're so desperately curious about this, take a look." Murasame rolled away from his desk slightly to let Ikaruga read for herself. "To be honest, I think you're going to be in the right to know this, considering you were just talking about it."

Murasame scrolled through the last few next pages before stopping on a specific entry for his sister. It was dated a few weeks before his sister had even gone to Kyoto. Not only did this mean that Dōgen returned to the facility after his defeat at Hebijo Academy, it meant that he was even active within the project itself since there wasn't any mention of the facility being abandoned yet. In fact, there was no mention of it anywhere. His last entry was a few days before the yōma incident in Kyoto to which he wouldn't be able to return to the journal after his final demise.

"Between the time when he used Hebijo Conquest and the Kyoto Incident—"

"You're giving them proper names now?"

"—he was able to summon the Yōma Generals," Murasame continued, ignoring Ikaruga's curiosity. He pulled up the Kyoto Incident's reports from last year. Some of the information on Dōgen came from the legendary shinobi, Hanzō, who was present at the site. He scrolled through to the relevant information to match up with the journal. "The timeline fits with this entry, even explaining the process in which he did it. This was probably for future reference if all worked out well."

Ikaruga could remember those enemies like it was yesterday. It was a group of ten powerful yōma that was under Dōgen's hand that were summoned using the blood of her friends and those from the Crimson Squad. Going up against one of them was almost like going up against the person that yōma had copied, but in each of the fights, the shinobis were able to come out on top. After all, they were mindless puppets at the end of the day and that would never be able to trump the genuine articles.

"The part I'd like to know more is this domination effect that he was mentioning here. Summoning the yōma, even if it was under all the right conditions, does not make it instinctively loyal to a human. Yōma are monsters who crave blood, carnage and chaos, so the idea that they would serve anyone from right out of the floodgates is an impossibility. Dōgen even said so himself here."

"From what I heard, Dōgen was a shinobi who was experienced in puppetry arts. Perhaps he could have used that on a higher level form?"

"No, it involves the experiments they've performed in their branch. If it was a shinobi technique that brought on their loyalty, there would be an entirely different story here, but it was that central experiment that provided the breaking point information he needed to conquer those generals. Of course, only vague details about what that breaking point was is given."

He was starting to wonder if there were more data that they somehow missed out on. He didn't grab everything that there was on the machine, but if everything was titled and sorted properly, then there shouldn't have been any important information that was overlooked. He did digress and continued.

"It's supposed to be some kind of innate attribute that you apply to yourself to make yōma instinctively bow down, but it's somewhat conditional and what works for one yōma won't work on every yōma. Sounds kinda fucked, but I'm not the one that makes the rules. If Dōgen was the only summoning the Yōma Generals into existence, it would make sense that he would know what attribute he needed for himself, especially if the baseline was blood he was keeping for himself."

For some reason, it made him shiver to even consider that there was some creep out there who had a sample of his sister's blood for their own occult bullshit. If Dōgen was still alive, he would have swung at him with everything he had for doing something so batshit insane with the Houou blood.

"All of this would be useful information for the shinobi to know. This can be a way for them to look into part of the organization and discover a way to disrupt their plans if they are planning to move forward with this idea," Ikaruga nodded, confirming what Murasame said for herself as she gently took the mouse from Murasame to scroll for herself. "However, that's an assumption. If this information was left in Dōgen's secret room, there is a real possibility that his organization doesn't know about this."

It was an easy assumption to make.

If that was the scenario, then they have access to the remaining copy of this particular research. Of course, they would have to head back as soon as possible to delete the original files, but other than that, they were holding critical data that the organization might want desperately.

Murasame just couldn't see that being the case though.

"Something about it feels wrong," he muttered under his breath. "It's not adding up."

Dōgen made his intentions clear to the organization that he must have not been interested in cooperating with their ideals any longer. The original destruction of Hebijo, as Ikaruga worded it, could have been certainly attributed to aligning himself with the organization's ideals, but the second attempt at Hebijo couldn't be excused when he wanted world conquest.

How was he able to return back to the facility without any repercussions from the organization? The room was a secret, but the facility wasn't hidden away from the organization. He might have been a main director, but he then had equal power to three others who might have viewed his actions as treason and one more higher-up who wanted the plan to go as smoothly as possible. If that meant cutting out a deserter to their cause, Murasame could see it happening.

"... If anything, I'd like to know more about this central experiment."

"Wouldn't that be the million yen question?" Murasame's words were rather droll. "According to previous entries, Dōgen didn't really show much interest at the start, contributing only his fair share of the money needed to fund the research. However, things started evolving and he took a closer look, even getting involved with some of the testing."

"I must assume that this central experiment is some kind of trump card—or perhaps even the true end goal of this organization. The sooner we can confirm what this experiment is, the better chances the shinobi council will be able to move out and dispatch it."

Everytime Ikaruga mentioned the shinobi council, he would internally wince inside. He told her things about what happened at the facility and mostly what he learned from the masked man, but just as he avoided mentioning it to the detective, he didn't want to tell her that he was suspicious of the shinobi council—at least, that there was a high chance that there was a mole on the inside.

Move out and dispatch it? It would be more like the mole would find a way to tuck it away and avoid any shinobis sent their direction, only bringing about more aggression towards the people who sent in the information. Now was not the time to reveal their hand yet.

Murasame sighed. He was ready to put a lid on this investigation for the night. Just as Ikaruga was coming in to remind him, he knew he needed to take care of the traps as soon as possible.

"We can leave this for another—"

"Do you think Isayuki would know about it?"

"... the kid?"

Murasame glanced at his sister as she was focused on the screen. The words came out of her mouth almost emotionlessly, as if they were out of necessity rather than a simple question of curiosity. He was left a little dumbfounded at the first beat, but he shook his head as he understood what she uttered.

"What? No way! How could a kid with amnesia be able to tell you anything!?"

"It can't be argued that he has some kind of connection with this organization. You told me yourself that the perpetrator invaded the hospital in order to capture Isayuki."

"W-Well, yeah, but that doesn't mean shit!"

"He knows who Isayuki is." Ikaruga backed off from the monitor and took a few steps back. "That's what it means. He feels that it is important that Isayuki is to be taken back underneath their wings. That means that Isayuki, at least the person Isayuki was before his amnesia, likely knows more about the organization that we could find out on these journal entries, specifically because he was there."

Murasame scowled at her. "What are you implying?"

"I don't want to believe it, but as shinobi, we must be on our guard at all times. We need to consider the possibilities in order to make sure that success is attained. I'm not saying that we shouldn't trust Isayuki, but I want us to be careful around him."

"I don't make wrong choices!" He slammed his fist on his desk. "Who do you think I am!?"

"Can you tell me why Isayuki was floating down the river when you first found him?"

Murasame froze, unable to respond.

"Considering what you've learned about his ties, there could be numerous theories that could paint him in all the right or wrong colors. You cannot be certain which is what." Ikaruga could tell that Murasame wanted to argue and she realized she came off a little too strong. She took a deep breath and relaxed. "I say this with love and care, Brother. I don't want you getting hurt at the end of all this."

She always had some skepticism about Isayuki, being able to hide it very well, but their return to the facility made her more suspicious about Isayuki's background. If he didn't have lots of common sense, clinging onto Murasame's word as if they were the law, it was strange that he would admit that yōma would be a familiar term to him, as if he knew they were more than a folklore.

"I'm not getting hurt," Murasame growled. It was like he was a cornered animal as he stood up from his seat. "I'll believe what I want to believe until I decide otherwise. Do you understand, Ikaruga!?"

She sighed, reluctantly letting her words be defeated. Her brother was a stubborn person until the bitter end and she knew this more than anybody. Letting him know what was on her mind to let that sit with him was the only thing that she could have done.

However, Murasame knew this denial was fair for her. After all, the masked man referred to Isayuki as an experiment, a thing that they simply wanted to retrieve. He believed that Isayuki didn't like the masked man, perhaps even before his amnesia, due to his instinctive dislike for the man when they first encountered each other at the hospital. That felt like a reaction from the core, a feeling that surpassed memories, and his innocent personality came off naturally, as if that was his baseline essence.

And then there was the fact that there was such a degrading tone from the masked man, as if the supposed prototype was nothing except an afterthought. At the very least, Isayuki was absolutely not the end goal of the central experiment, but perhaps he was a byproduct of it. That was, if he could even believe what the masked man even said anymore, but considering the circumstances, he was willing to wait for concrete evidence before trusting another sentence from the man.

However, it wasn't as if he couldn't see it from Ikaruga's perspective.

"If you want to keep tabs on him, be my guest. Are we done here?"

"I apologize. I didn't mean to ruin your mood."

"... Who said anything about that?" he scoffed. "I needed a break to begin with."

He really wanted to put an end to this conversation though, so Ikaruga hadn't been wrong.

The worst thing he could imagine before heading to bed is having a sour topic lingering in his mind before a night's rest. It wasn't as if the atmosphere was tense between them, but it was as if a heavy weight was placed on their shoulders. Even as they said nothing to each other, it was like that weight simply became heavier and heavier every passing second.

For some reason, Murasame felt like it wasn't his imagination until a chill ran down his spine. It caused him to stiffen, forcing him to break out into a sweat. Murasame glanced around him, trying to figure out what the hell was going on because at that point, he knew it wasn't his imagination anymore. He glanced back at his sister, seeing that her guard was completely raised as she turned towards the door.

She brought out her scroll which summoned her long nodachi into her hands and she bent her knees, falling into her combat stance. Murasame should have taken a hint at that point, but he stumbled onto his feet with confusion wincing in his eyes.

"H-Hey, Sister? What's going on?"

"Keep your head down!"

Something sprung through his doors, causing him to follow Ikaruga's words unintentionally. He dropped to the ground on all fours as Ikaruga drew Hien from its sheath, breathing out a single slash. He didn't even get a chance to see what it was before it got sliced into two parts. It crashed onto the ground, giving Murasame a moment to pause and think. He looked over.

"What…? What the hell is that…?"

Murasame couldn't dare to call it a snake, but its serpentine body begged to differ. However, its sharp edges along the spine and irregular cravings along its body made it look more demonic in nature. The problem had been when he looked on its insides. It didn't have a fleshy interior, but instead mechanical parts, quite literally as in gears turning the cogs and wires holding everything together.

Something that was made to look like a yōma, but it was actually a machine. If it was really a yōma, it would have started disappearing, but the red eyes were the only things that did that. There were so many questions stirring in his mind, but there was something important he needed to address.

He coughed loudly before dusting himself off, getting himself back on his feet.

"W-Well, that was sure something." He glanced towards the door, wary of anything else that might have been around the corner. "Now to figure out what's going on."

"Whatever is happening, a shinobi barrier was erected."

Murasame frowned at Ikaruga's observation.

Shinobi barriers were typically used by shinobis in order to combat other shinobis without the public being able to detect them. No one else would be able to get through the barrier otherwise. The problem is that the thing that just attacked them was definitely not a shinobi or else Murasame would have some serious concerns that they were letting things like that have such a title while leaving him with nothing. In other words, there was still a culprit out there.

"We are under attack, Brother. Head to the safe room."

"Are you kidding me!? They broke down my door! I need to make this bastard pay!"

"Later!" Ikaruga raised her voice sternly. She raised her arm out. "They're not making their presence hidden at all. Somebody is waiting for us downstairs in the lobby with immense bloodlust. I can feel my hair rising just from the pressure."

Murasame bit his lips. He wasn't sure what she was talking about because he couldn't detect anything, but if Ikaruga was on edge, he needed to take her word on it.

"Fine! I'll only listen to this once," Murasame sighed, "but it's only because I'm feeling tired. If I wasn't in this state, I would have taken them down myself!"

"Then please leave this to me in your stead."

Ikaruga dashed out from the room and headed over to her objective, leaving Murasame to awkwardly leave to where the safe room was. Nearby, there had been a reinforced room where it was difficult for most shinobis to penetrate. It should have been enough to shield him away from the time being, at least until Ikaruga is able to take down their opponent.

He still had to be vigilant.

If there was one of those machines, there might have been more. His mind couldn't break away from what that thing might have been. Actually, the important concern should have been the reason. It should be fair to assume that this was an intentional attack, but it left Murasame wondering if it had anything to do with the yōma operation.

After all, he couldn't think of a better time. If they were discovered to be snooping around the facility, it would be fair that they would throw down the gloves and let all hell go loose on Murasame as they would then register him as a definite enemy. If that was the case, he really couldn't trust whatever that masked man said during his parting then.

Then what was the whole deal with the machines?

"Wait a minute… Didn't that guy mention there was a branch of mechanization?"

"Indeed. That would be correct."

Murasame widened his eyes to hear an unfamiliar voice. He whipped his head behind him, only noticing that the lights of their particular hallway had all been taken out. He carefully stepped back, sweating profusely with a giant gulp.

"Who's there!? Show yourself!"

From the shadows, a figure made itself known. As if it was the rhythm of a ballad, their footsteps echoed through the hallway, becoming louder and louder.

"I come as a representative belonging to the branch of mechanization."

The moonlight from the windows finally revealed the person's appearance.

It was a girl, probably around Ikaruga's age, though a little shorter. She had black hair with a red hue and her golden eyes sparked within the darkness. Her skin looked almost pale, as if she was a ghost herself, but what made Murasame hesitate was the strange clothing she was wearing. It was simply a traditional maid outfit. He didn't know who she was serving, but it was definitely no one in this residence.

In her hand, she held a black briefcase to her side.

She raised her other hand, extending it towards Murasame.

"I heard you were a businessman. Let us do some business then."

"I thought I already gave my damn answer to your boss!"

Murasame swore under his breath. He wasn't sure how this girl was able to slip past his sister when it felt like this was the source of the blood lust, but there was no more time to think. He hadn't recovered from his fight in the facility yet. His sickle was still broken as well; he hadn't had time to repair it, so he was stuck in a rough situation.

He clenched his fist and fell back a few steps. If his personal weapon couldn't be used, the best he could do was work on intimidation. He raised his arms, holding a combat stance, the same one he explained to Isayuki. The only problem was that while he had the idea down, he didn't have much confidence in its execution. That being said, he couldn't be flexible.

"Oh, him? I find his methods to be strange at best, so my type of business is far more direct."

Her hand clenched. Murasame could feel her strength from a distance.

"I'll make this simple. Give me what you took from the facility."

"And if I refuse?"

"If you refuse?" the maid chuckled. "I see. You're prepared to die. For such an esteemed businessman, it seems like you're still capable of making bad deals."

"You think you're going to kill me?"

Murasame closed his eyes. He could already feel his body suffering through the stress of the situation, but he pushed himself through it regardless. If he was ever good at anything in a fight, it was being stubborn and durable. And now, this was the one time he prayed he was correct on that analysis. He took a deep breath and open his eyes.

"Come on!" Murasame bluffed. "I'd like to see you try!"