On my next day off, I decided to visit the workshop of the mechanical engineer again to talk about the prosthetic hand.

　This time, I'm not with Sakura, but Garnett.

　I've already had a meeting with him beforehand, so I just showed him my face and he immediately led me to the back of the workshop.

　After they took off their upper body clothes, they sat me down on a chair and gave me a lecture on how to install the prosthetic arm, along with a demonstration.

Then, let's get right to it, I'll explain the installation procedure first. Luke's whole shoulder has been taken away, so the base of the prosthetic arm is finished to cover his whole shoulder.

　Alexia is standing behind me, making preparations for this and that, while continuing to explain about the prosthetic arm that will be installed.

"Bran was in the form of his arm that was torn off in the middle of his arm, so we were able to fasten a belt around the remaining part, but in Luke-kun's case, we'll have to use his torso to hold it in place.

　A cover covering the shoulder and section is pressed directly against the prosthetic hand that mimics the entire arm.

　While I hold it in place with my left hand, Alexia deftly wraps the cloth belt around my body, securing the prosthetic hand firmly in place through the back of my neck and left side.

　Garnett watches the scene absentmindedly from beside me.

　It may or may not seem like he's watching Alexia's hand, but I wonder what on earth he's thinking as he observes.

This is all right ...... I installed it over bare skin for clarity this time, but if it hurts or feels uncomfortable, please wear it over your underwear.
I don't think I can do this alone.
This is the last thing I expected. Since you have a roommate, why don't you ask Garnett?
'Heh?　Oh, me?

　Suddenly the subject was turned around and Garnett rolled his eyes and let out an upturned voice.

'And he's the closest person to me. And it doesn't look like your brother is going to do it.
"......, for heaven's sake. ......

　Garnett mumbled and looked sideways at my upper body - technically a device that secures a prosthetic hand to my body - while muttering.

　Well, ...... this time it's just a practice for clarity's sake.

　I'm sure you'll be able to find a way to make it easier to understand. It's a good idea to have it over your underwear for various reasons.

'Well then, try moving it around. It should feel fine, just like moving your right hand normally.
How's that?

　I tried to move my right hand as I was told.

　Then, strangely enough, the fingers of my artificial right arm, which has the same structure as the autonomous doll, began to slowly open and close as I thought they would.

　Of course, it's not just the fingers.
　I could bend my elbow and raise my arm higher than my shoulder just as I wanted.

'Awesome!　How does it work?　And it's lighter than I thought it would be: ......
The control method is the domain of the wizard, so I can't say for sure. We're just modifying it so that it can do what we ordered it to do.

　I took the shirt Alexia offered me with my right hand and went straight through my arms and neck as I normally would.

　As expected, it wasn't up to the senses, so it seemed to take some getting used to moving it properly by groping, but even with that in mind, it's a great achievement.

But even with that, it's a great piece of work. The prototype was quite heavy. The weight of the prototype was quite heavy, so we made it the same weight as the left arm, but in order to keep it balanced, we made it lighter in various ways.
I see. Are you battle hardened?
'I can handle the logistics like you do, Luke. You can't wield a sword or a spear. It's probably not going to work with a bow either. The strength of the body is the same, but the base of the bow isn't that strong.

　That area is expected to be developed in the future, Alexia added in a bouncy voice.

　As expected, it doesn't seem to be a complete replacement for a real arm at the moment.

''Then it will depend on whether or not it can lift heavy objects and whether or not its fixed parts can withstand it.
Yes, I think the fixed system needs improvement. Luke-kun could make it [fuse] to the human body so that it doesn't come off, but this is part of the research that is based on the premise of widespread use.
What's going on with the power source?
''For now, it's in the form of using Luke-kun's magic power. There's a way to use the magic crystals, but we'll start with a simple structure.

　Both me and Alexia unknowingly had a smile on our mouths.

　Garnett, too, seemed interested, stroking and holding the artificial hands that peeked out from the sleeves of his jacket.

　--I as an adventurer. Garnett as a knight. Alexia as a mechanic.

　Each of us appreciates this elaborate prosthetic hand from a different aspect -- or a similar aspect.

　Due to their profession, both adventurers and knights have a higher risk of losing a limb than the average person.

　Even with the current performance of the prosthetic arm, it would help such injured people to retire and live a life like a normal person, and if the performance is improved, they may even be able to return to the field.

"But then again, there are people out there doing this kind of amazing research.
'Yes. It will definitely change the face of society when it's completed. But it seems that this would not have been possible without Luke's help.

　Alexia smiled strangely and proudly as she began to clean up.

'I found out after actually playing with the contents that the internal structure of this arm is quite influenced by the autonomous doll. The reason I was able to adjust it so quickly is because of my experience in analyzing the recovered autonomous dolls.
''You mean, if we hadn't defeated the Night Ripper or proceeded with the search for the Ark of the Elements, it wouldn't have been completed so quickly?
'What we discover will change the world in the hands of other experts. It's a great thing to be an adventurer, isn't it? Well, me and Luke, you and I both have other jobs as our day jobs.

　You are absolutely right.

　Basically, an adventurer is a 'searcher' and a 'discoverer'.

　In many cases, this is just a part of exploration and treasure hunting, but it can also be a chance to change the world by pulling out things in places that would normally be impossible to find, right in front of the eyes of those who have the appropriate knowledge.

...... By the way, I was going to ask you about it sometime.

　Garnett interjects in a divine manner as me and Alexia's conversation pauses.

''How far has the autonomous doll's analysis progressed?　If you found out anything, I'm sure the White Wolf Knights would have a report for you.
'Hmm ...... I'd say you can guess when there's not much to report. I've been able to analyze the ends of the limbs and other parts of the body enough to make such a prosthetic arm, but when it comes to the contents of the head and chest, it's still not as good as it should be.

　Alexia looked troubled and tapped her head with her fingers.

'It's so complicated and unintelligible, it's a black box that I can't even figure out how to reverse-engineer it.
'Well, ...... d*mn, I was hoping for some clue as to how to take them down, at least somewhat.
This is just a metaphor. If you take the human head physically apart, you can't understand how emotions and personalities are created. You feel that level of incomprehensibility.

　If a technician as good as Alexia is like that, then a complete analysis of the parts that can be called the core of an autonomous doll is really impossible for today's humans to do.

　Even if I look at it with my right eye, I may understand its general function and use, but I don't know the specific mechanism, so I have to say that there really is nothing I can do about it.

　As I was thinking about this, Alexia, in a casual manner, uttered a single word that strangely made sense to me.

'Perhaps the dark elves who are being held hostage by Luke-kun's right arm might know something we don't. They're also doing something nonsensical like 'body replacement'.