The bedside lamp gave off a faint, comfortable glow. Sitting on the edge of the bed in his pajamas, Cid looked expressionlessly at Eta, who stood by the door. After confirming that it was night, he raised an eyebrow.
"This is rare. With your schedule, Eta, you'd usually be asleep by now. You also deliberately avoided me earlier to go talk to Asia. Is something going on?"
His voice was calm, but as if he had found something interesting, a trace of curiosity entered it. Cid narrowed his eyes, his deep gaze fixed straight on Eta.
Under Cid's stare, Eta felt even her heartbeat quicken. Still, in order to patch the loophole involving Asia that might cause her plan to fail, she walked in.
"Master, did you give the gift I gave you to Asia to drink?"
Eta's voice was as flat as ever, but there was an inexplicable pressure in it.
"I did. How did you know?"
Cid admitted it directly without explaining. It was not a big deal anyway. Eta had already given the thing to him, so what was wrong with letting Asia, his new subordinate, drink some?
Rather than worrying about that minor issue, Cid was more curious about how Eta had found out. Because of Asia's arrival, the milk in the fridge had long since been finished. He had already been planning to tell Eta to send an extra portion next time.
"...I was thirsty and wanted some."
Eta's mind froze for a second at the unexpected question. After quickly sorting through the possibilities, she gave an answer that left the explanation entirely in her hands.
"Mm... That's a pretty reasonable explanation. Unfortunately, because of Asia, our milk consumption has doubled. Everything you sent has already been drunk."
With an expression of sudden understanding, Cid said it in a tone as if it were only natural.
"I'm a little angry. It was a gift I gave to Master, but Master gave it to a vulgar person."
Eta's expression did not change, but there was a hint of dissatisfaction in her voice.
"You have a point. Giving something you gave me to someone else does seem a little inappropriate. But once something is in my hands, the right to decide what to do with it is also mine."
Cid nodded in agreement, but he showed no intention of apologizing.
"I want compensation."
"Sure. What compensation?"
Cid agreed to Eta's completely unreasonable demand as if it were nothing. He would not apologize for giving something of his to someone else, but he did acknowledge that what he had done was not quite right.
"I want Master to help me handle this."
"Huh?"
Cid let out a startled sound without thinking, staring blankly as Eta used a slime tentacle to pull a sheet of paper from her chest and hand it to him.
"Why do I feel like you planned this from the start?"
With a strange expression, Cid took the paper. The sheet should have been white, but it was covered with dense magical runes. Cid focused on it.
"Ancient runes from the ancient artifacts of our world, a hybrid of the power systems from the myths of World One, World Two's unique magical technology, and some messy things I don't know the origin of... Where did you get this? It's like you took the essence of every field."
Cid could not be blamed for being surprised. The value contained in this single page was already comparable to the Library. The Library contained all knowledge from World One, and it was even a conceptual treasure that automatically updated with the passage of time.
But the writer of this page had integrated knowledge from three different worlds. At the very least, they had integrated the knowledge recorded on this sheet.
"I made it together with a pen pal."
Faced with Cid's confusion and surprise, a flash passed through Eta's eyes before she answered with an unchanged expression.
"You have a pen pal?!"
Cid suddenly looked up at Eta. He felt that he was learning more and more strange things today. Eta, who would not give anyone a friendly look besides the Seven Shadows and himself, actually had another friend. Not only that, but it was a pen pal she could discuss research with.
"Mm. There's a topic we both like very much, so I suppose we can be considered fairly good friends. At least for now..."
"I can tell. You're pretty fond of her."
Noticing the sinister smile curling at Eta's lips, Cid silently mourned for that pen pal. Eta's smile clearly meant she was about to trick someone.
Still, it made sense. If that person could become good friends with Eta, she must have research abilities just as incredible as Eta's.
"This is kind of terrifying. There are actually two geniuses who can integrate the knowledge of these three worlds in just over a year, and those two geniuses even know each other... Interested in destroying the world?"
"...Master, are you mocking me?"
A very obvious look of confusion appeared on Eta's expressionless face, as if she were genuinely wondering whether Cid's words had been sarcasm.
"Why would you think that?"
"You recognized the origins of all the magical runes and techniques on it with just one glance..."
Cid stiffened. He really did not know how to explain to Eta that he had merely dabbled a little in every technique system. In truth, if he had to be honest, he had already almost forgotten all that knowledge by now.
As mentioned before, once the Magical Power of World Three left the body, it became very difficult to control. Because of that, most people in World Three chose to become close-combat Magical Swordsmen. But that did not mean World Three had no magic.
In ancient times, people found another path. They chose to engrave runes with mysterious powers onto mithril objects, creating ancient artifacts one after another, each with all kinds of mystical powers. Unfortunately, as time passed, the technology to create ancient artifacts was lost, and people could only reverse-engineer them from existing ancient artifacts.
Even before the worlds merged, he had already succeeded in using ancient rune magic outside his body. After all, the only thing that kept the people of World Three from using magic was the issue of control, and his control happened to be just a tiny bit better than most people's.
As for World One's various magic systems... they were in The Library. Upgraded versions, even. Back when he first obtained The Library, his brain had not completely short-circuited yet, so he had studied each magic system step by step. Until he discovered that the so-called upgraded versions actually had backdoors!
As for World Two's Magical Knowledge... he had once infiltrated the predecessor of Netheril, the witch organization that held all kinds of dangerous Magical Knowledge from World Two: The Library.
That unusual experience meant he had some understanding of all kinds of knowledge from the three worlds, but most of it was only surface-level. After all, later on, he obtained the far more convenient "Core."
"I only know a little."
"Is this what Master often calls humblebragging?"
"...Let's talk about this instead."
Unable to come up with a proper explanation, Cid looked away and changed the subject.
"Sure, Master. So is there something wrong with it?
"Because the sample is too precious and too rare, I only have one chance to experiment. That means I'm missing a lot of experimental data."
Eta nodded. She also knew what truly mattered, so she shifted back to the main topic and explained why she had come to ask.
"Mm... this?"
Looking at the various Magic Formulas written on the paper, Cid fell silent again.
He could not understand it.
The core knowledge was laid out on it, so he could tell what it was meant to do and how it was supposed to be used. But whether the Magic Formula itself had any problems, he had no idea.
He could use the Magic Formula on this paper in front of Eta right now, because the Core was the destination, while the Magic Formula was the map. Once he knew the destination, whether he had the map or not did not matter much. No matter what, he could reach the destination.
To put it more simply, his vehicle was an Anywhere Door. As long as he knew the location, he could arrive at the destination. For others, depending on their control and understanding of the "Core," their vehicles might be cars, planes, bicycles, or even their own two feet.
"How about... I demonstrate it once for you?"
Cid said this uncertainly. Even he did not know whether he could solve the problem on this sheet of paper.
If the person standing in front of him right now was not Eta but someone else, Cid would not mind throwing out a few cool-sounding lines and bluffing his way through. But when it came to his friends, he still did not intend to trick them.
"...As expected of Master. You learned something she and I worked so hard to create with just one glance. Is this some new quantum speed-reading technology?"
After a moment of silence, Eta said that with admiration.
No, no, no. A Magic Formula without any secrecy mechanism is basically like a naked drunk woman lying in the street to the "Core." You can get in even without using Magical Power.
"Let's begin, Master."
As Cid silently retorted in his heart, Eta pulled over a small stool and sat by Cid's bed, her eyes seeming to glow as she stared straight at him.
Cid's mouth twitched. He wanted to say something else, but for the sake of his image, he turned and took a Piece out of the bedside cabinet.
"Fine. I happen to have one of Rias's Peerage Pieces here, so I'll demonstrate it once for you. Let me say this first, though. Whatever you create after this has nothing to do with me."
"Mm-hmm, hurry up, Master."
"Fine, fine."
Cid answered half-heartedly while controlling his Magical Power to extract that drop of blood from Rias.
"First you do this and this... then that and that... and finally you handle it like this. Did you get it?"
Pointing at the highly concentrated Power of Destruction floating above the Piece in a single mass, Cid turned to ask Eta.
"So that's how it is. I didn't think there was another way to achieve it. There's a problem here that needs fixing."
Eta nodded as if she had understood something. She stared intently at the Magical Power trails that had yet to dissipate in the air, holding a notebook and pen from who knew where as she took notes.
No, what could you possibly have understood from that?!
Now it was Cid's turn to be shocked. Aside from the final endpoint, everything he had just done was completely random. It could be said that it was an entirely different type of Magic Formula from the one on the paper.
"Master, can you do it again?"
After finishing her notes, Eta turned her gaze back to Cid, her eyes shining as if pleading with him.
"..."
Cid fell silent. To be honest, even he did not know what to do now. Aside from his usual habit of putting a magic circle visual effect over it, the rest of the Magical Power trails had been completely random. That meant he had not even noticed which magic circle effect he had used.
"Master, what's wrong?"
Perhaps because he had been silent for too long, Eta asked curiously.
"No, nothing."
Cid shook his head. Magical Power gathered in Rias's Piece once more, and he bit the bullet, picked a random magic circle by instinct, and placed it over the Magic Formula.
"Wow. As expected of Master. You can even handle it this way."
As if she had not noticed that the Magic Formula displayed in the air had changed completely, Eta excitedly continued taking notes.
Seeing this, Cid narrowed his eyes. Could Eta have... realized from the start that the Magic Formula he displayed was just a visual effect, and was only pretending not to for the sake of his pride?
"Master, is there more?"
After finishing her notes, Eta continued looking at Cid. This time, however, Cid said nothing and merely lowered his eyes.
"Are you done messing around?"
"...I wanted to know how many methods Master has."
Faced with Cid's scolding, Eta did not panic. She only spoke slowly and calmly.
She really did notice!
"This time, I was in the wrong. I owe you one favor."
"Then I came out ahead."
A sly smile curled at the corner of Eta's mouth as she took out a gold necklace and handed it to Cid.
"What's this?"
"A gift for Master."
"...Where did it come from?"
Cid glanced casually at the necklace, and the question slipped out by habit.
"A magical tool I bought in Netheril."
Eta said this without the slightest change in expression, meeting Cid's gaze with her calm eyes.
"I'll accept the necklace. But in the future, buy fewer things from Netheril."
Hearing that it came from Netheril, Cid looked at the necklace suspiciously. Only after failing to see anything wrong with it did he accept it, though he still warned Eta solemnly.
Seeing Cid put it on, Eta said goodbye and prepared to leave.
"By the way, Eta, I don't think I know what you came here for. Travel doesn't really suit your personality."
Eta's body froze just as she was about to leave the room. After a moment, she answered again.
"I came to ask Gamma for my research funding back. I'm also meeting a pen pal while I'm here."
"Oh."
Cid answered, and Eta left completely.
...
Eta's Diary:
Since I rarely get to see Master, I'll write an extra diary entry.
There was a flaw in the plan. Asia actually drank that stuff too. If Master discovers Asia's abnormality...
Fortunately, I successfully tricked Asia into taking the Calming Pill, and I also explained things to Master's side. The plan needs to be accelerated, though. Asia isn't Master. Suppressing the symptoms without curing the root cause means it will erupt very soon.
Also, through observation, I discovered that Master is used to making two layers of magic patterns. The inside layer is the real one. But after using the ancient artifact to fleece him only twice, I was discovered.
I have fallen out with Master. The path to Shadow Wisdom has been completely cut off. The plan absolutely cannot stop. I haven't received Shadow Wisdom in an entire year!
I gave the necklace to Master. The thing inside was probably discovered, but I shifted the blame to Netheril and successfully made Master think I had been deceived. He even put on that problematic necklace. Heh. As arrogant as ever, Master.
If Plan A fails, then I can only sacrifice you to carry out Plan B, my friend.