April 13th was declared another day of free time. Since they were scheduled to depart the town of Miyako the following day, the 14th, Jin wanted to ensure no one had any lingering regrets.
"I have a promise to keep..."
Elsa caught Jin's murmur.
"Jin-nii, what promise?"
"You know, the one about making a library golem and showing them how to make sweets."
"...Oh, right."
That referred to the casual agreement Jin had made with Mii on the day they arrived, alongside his plan to scan the books in the Library.
"Are you going to make it now?"
"Yeah. I'm good at making golems, so I should be able to finish it up this morning."
After saying that, Jin addressed the rest of the group.
"I'm heading to the Factory."
"Then I'll go too."
"I'll be heading to the Library for the morning."
"Ah, me too!"
And so, for the morning hours, Jin and Elsa went to the Factory, while Saki and Hanna headed for the Library.
"Saki-sama, may I accompany you?"
"U-Uh, sure."
For some reason, Mii had taken a stronger liking to Saki than to Elsa. Saki herself looked rather bewildered by the attention.
"Welcome. How may I help you today?"
At the Factory, the Factory Manager Automaton greeted them just as it had the day before.
"I have something I want to build. Could I use a section of the Factory? I'll also need some materials."
The Factory Manager Automaton nodded.
"Yes, that is acceptable. Please let me know which materials you require."
It appeared that private use of the facility was permitted.
"Please use this area."
They were guided to a fairly spacious workspace.
Looking around, Jin felt that there really ought to be more people using this place for personal projects.
"Thanks. For materials, I'll need about 30 kilograms of bronze. Also, seven magi-crystals of a quality suitable for control cores, three regular-quality magi-crystals, and 20 kilograms of magi-resin."
"Understood. Right away."
The Factory Manager Automaton ordered working golems to bring in the materials Jin had requested.
"All right, let's get to work."
"...Jin-nii, what about the materials for the magical muscles and magi-nerves?"
Elsa voiced the natural question.
"About that—I'm not using them this time. Considering the maintenance, the locals won't be able to service it if I use Hourai Island specifications."
This was a conclusion Jin had reached after inspecting the golems inside the Factory.
"The maintenance golems in this Factory probably wouldn't know what to do with Hourai Island specs. If I'm leaving it at the Library, it needs to be maintenance-free for the next hundred years or so."
If he used the system known as 'Form Drive', Jin could make the golem almost entirely maintenance-free. Even if something did happen, the Factory's maintenance golems would be able to handle the repairs.
"...I see."
It was rare for Jin to build a golem using the 'Form Drive' system.
To be precise, 'Form Drive' was the system used in the golems created by the Negadolls, so in a way, this was his first time building one from scratch using that method.
The technique he had used when repairing the prototype golems that became the basis for Gon and Gen in Kaina Village was more accurately described as a 'Forming' movement system.
"Thank you for waiting."
Just then, the materials Jin had requested were delivered.
"Thanks. Just put them there."
With the materials gathered, Jin finally set to work.
"...Thinking about it, this is my first time seeing this."
It seemed this was also Elsa's first time watching a 'Form Drive' golem being constructed.
"Well then, watch closely....Though I'm not exactly an expert at this style myself."
"Mhm."
A Form Drive golem was relatively easy to build, provided one was just looking for basic functionality. It was, so to speak, a beginner-level golem.
"First, I'll shape the body with magi-resin."
He applied 'Forming' to the magi-resin, molding it into the desired shape. Since it was destined for the Library, he chose a slender, androgynous build.
"Next is preparing the control core. Though it doesn't really matter whether I do this or the resin molding first."
As he explained, Jin crafted the control core, the ether converter, and the mana driver.
"Since this one is for the Library, I'll use high-quality magi-crystals for the eyes as well."
"Okay."
Two magi-crystals remained from those prepared.
"One is for auxiliary memory."
He intended to have the golem memorize every book in the Library.
If it were the National Diet Library of modern Japan, a single magi-crystal would obviously be insufficient, but the scale of the Library here was smaller than a typical elementary school's collection, so this would be plenty.
"What about the other one?"
"I'll make it into a 'manacam' so it can send information back to Laojun."
That way, it would be secure in terms of data backup as well.
"I'll set it to transmit only, so there's no chance anyone could trace it back to Laojun's location."
Conversely, if anything happened here, Laojun would be able to sense it.
"The rest are the ears and the vocalization device."
He used the regular-quality magi-crystals for those—two for the ears and one for the vocalization device.
"All right, the internals are complete."
It would technically function as it was, but it was made of resin; it looked unfinished and had low structural strength.
To remedy that, he would use the bronze to add an exterior shell.
Unlike a human-shaped golem with complex internal machinery, the interior was a solid body of magi-resin, so he didn't need to worry about precise joint placement. The only concern was mobility.
Broadly speaking, as long as the joint areas could bend, any design or structure would work.
"...And so, Elsa, why don't you try making the exterior?"
"Eh, me!?"
Elsa was startled by the sudden request.
"That's right. You know I'm not great at aesthetics, don't you? This is your turn to shine, Elsa."
Since it was meant as a gift, he wanted to avoid a rugged, purely functional appearance.
"Mhm, I understand....'Forming'."
Elsa was also top-class when it came to magi-craft. She finished crafting the bronze exterior in less than thirty minutes.
"Good, all that's left is to fit it on."
Because the interior was magi-resin, it was easy to adjust whether the fit was tight or loose, making the assembly highly efficient.
With the two of them working together, the job was finished in ten minutes.
"Jin-nii, what about its knowledge?"
Since the control core was already embedded, she was curious about how he would perform the 'Trans Info'.
"Ah, this magi-resin conducts mana very well. Even with the golem finished, as long as I remove a piece of the exterior, I can easily write to it."
"Oh, I see."
This library golem's strength was only about one and a half times that of a human. It was completely unsuitable for combat.
Therefore, he hadn't implemented any countermeasures against Master-Slave Rewrite Magic.
"So, I've been thinking about what to do for its knowledge base. I figured using the same data as the Golem Maids would be best."
"The Golem Maids'?"
"Yeah. They have more than enough knowledge, and their behavior is excellent. I won't make it a simple copy, though."
"I understand."
Jin contacted Laojun through Reiko and had him send a magi-crystal containing a copy of the knowledge from Perido, who handled the most housework among the 5-Color Maids.
The magi-crystal was transferred via the warp gate in about two minutes. Jin then proceeded to transfer the necessary knowledge from it.
"Trans Info, Level 5....There, that's done."
All that remained was to take it to the Library and transfer some of the librarian's specific knowledge, and the project would be complete.
"We still have time. Let's do that other thing too."
The time was 10:30 AM.
"Jin-nii, are you making something else?"
"Well, there was that kagami mochi. But when I asked the dining hall staff at the Guest House, they said they'd never even heard of eating such a thing."
"Wait, what are you talking about?"
Jin answered Elsa's question with a mischievous smile.
"That's a surprise. You'll see."
"...Honestly."
Jin could be like this sometimes, teasing her by being mysterious. Elsa gave him a mock pout in response.