"A barrier cushion car?"
"Yeah, exactly. I’ll lower the rigidity of the barrier to match the unevenness of the ground and deploy it beneath the vehicle. That way, we won't need tires, continuous tracks, or legs."
Jin set to work on a prototype even as he explained the concept.
Reiko and Elsa watched with intense interest, helping him where they could.
Once the prototype was finished and moved to the plaza in front of the laboratory, Jin prepared to climb inside, eager to prove his theory through action. Naturally, it was Reiko who stepped in to stop him.
"Father, please leave the test run to me."
Reiko had performed the initial tests for nearly every vehicle Jin had ever built. Insisting on her usual role, she climbed into the driver's seat.
《I am beginning the trial.》
An external speaker was attached to the craft, allowing her voice to carry clearly across the plaza.
The magi engine hummed to life, and a magical barrier materialized across the bottom of the hull.
Jin observed the craft for a moment and realized the barrier's hardness was set a bit too high; the ride looked like it would be uncomfortably stiff. It was even slightly gouging the ground beneath it.
"Reiko, lower the barrier's hardness a little."
《Yes, Father.》
By adjusting the hardness based on the terrain, the barrier's shock absorption could be fine-tuned. With the adjustment made, the craft stopped scarring the earth.
Furthermore, by varying the output "strength," they found they could adjust the vehicle's hovering height within a range of roughly ten centimeters to one meter.
With the basic hovering parameters established, they moved on to the driving test.
"Alright, Reiko. Try moving forward slowly."
《Understood.》
The craft used a force generator for propulsion.
The prototype glided forward as if sliding on ice. It left virtually no trace upon the ground.
"Oh, it's a success!"
"It’s amazing," Elsa added, her voice filled with genuine admiration.
It was likely the first time she had ever seen an automobile with neither wheels nor legs travel while hovering a full thirty centimeters off the ground.
The craft reached the edge of the plaza at roughly twenty kilometers per hour before performing a crisp U-turn.
On the return trip, Reiko doubled the speed to forty kilometers per hour before bringing the vehicle to a sudden, dead stop.
Such a maneuver was only possible because of the force generator.
Because the device exerted "force" upon the vehicle's entire structure—affecting every individual molecule and atom—the pilot wouldn't feel the effects of inertia or G-forces, no matter how quickly they accelerated or decelerated.
"Good. Now for the flight performance. It's all yours, Reiko."
《Yes. Here... I go!》
This time, the prototype rose vertically into the air.
Reiko was an expert pilot, and the craft was equipped with a secondary control core as a backup, so Jin was able to watch her maneuvers with total peace of mind.
《It can easily maintain a speed of one hundred kilometers per hour.》
"Alright, that’s plenty. Good work."
If they needed to travel long distances, they could simply use a dedicated reconnaissance aircraft. Jin was more than satisfied with the prototype's current performance.
＊ ＊ ＊
Before they knew it, evening had arrived.
"Today was another productive day..."
Jin headed home, feeling a sense of pleasant exhaustion.
As he soaked in the hot spring and stretched out his limbs, he could feel the fatigue that had pooled in his shoulders and neck simply washing away.
"I can't wait."
The thought that he would finally be going to the Moon in just a short while filled Jin with excitement.
"...Even so, a spacesuit, huh..."
"Father, it would be best if you could be satisfied using a 'Body Double' (Double)..."
Reiko spoke up, responding to Jin's quiet murmur. She was still deeply worried about his safety.
"I will no longer try to stop you from boarding the spaceship. However, when it comes to exploring the lunar surface, please leave that to a Double."
When they had raided the Unifilar headquarters in the past, Jin had stayed safely aboard Pegasus 1 to issue commands, leaving the actual infiltration to a Body Double.
"Hmm..."
"If the current models are unsatisfactory, you could always create an even more advanced Body Double..."
At Reiko's suggestion, Jin's eyes lit up.
"That's it! Why didn't I think of that? I've got it, Reiko. Let's do it!"
He let out a cheerful shout, his creative drive clearly ignited by the idea.
"...Hmm, but if I share its senses, I'll end up taking damage too..."
Jin was half-distracted throughout dinner, and by the time the meal was over, he had fallen into a state of total, single-minded absorption.
"...Reiko-chan, did you say something to him?"
Elsa asked the question in a slightly stern tone.
"...My sincerest apologies. Because I do not wish for Father to put himself in danger, I suggested that he create a high-performance Body Double instead of a spacesuit."
"...I see."
It was exactly the kind of project Jin would jump at.
"...In that case, why don't we all work together to help him finish something truly wonderful?"
"...Elsa-sama... Yes!"
Reiko had been looking a bit dejected, but she lifted her head at Elsa's encouraging words.
"Master, I believe the key will be the limiters," Anne suggested.
"Yeah, you're right."
Sight, hearing, smell, taste, and tactile sense—all of these would be transmitted to the operator. However, any sensation exceeding a certain threshold would have to be blocked.
If they didn't do that—for example, if the sense of pain were transmitted directly—then any attack the Body Double suffered could cause actual damage to Jin, even though the machine itself would be fine.
"Sharing the senses is a must. I want to feel as though I’m actually there."
Since he couldn't physically set foot on the exploration site, Jin's greatest wish was to experience it as vividly as possible.
"But please, ensure the body is as durable as it can be."
"It shouldn't just be durable; make sure its strength and speed are the absolute best possible."
Anne, Loll, and Refa all offered their technical insights.
Specifications were decided one after another, and a complete blueprint began to take shape in Jin's mind.
"Jin-nii, you won't actually start building it until tomorrow... right?"
Noticing the worry in Elsa's eyes, Jin gave her an obedient nod.
Thanks to everyone's help, it was still only 10:00 PM.
"Thank you. I’ve got the general specifications worked out. I'm going to turn in for the night."
"Understood. Master, good night."
"Good night, Master."
Loll and Refa bowed and withdrew.
"Master, sleep well."
Anne stepped into the adjacent room, and Elsa followed suit.
"Good night, Jin-nii."
Elsa returned to her own room, leaving only Jin and Reiko behind.
"Ah, Reiko... thanks to you, I think I can make something really special. Thank you."
"No... I was worried that I had overstepped."
Jin reached out and patted Reiko on the head.
"Not at all. I'm truly grateful. Now I’ll be able to enjoy space in complete safety."
With that, he crawled into his futon.
"Good night, Reiko."
"Please rest well, Father."
The light of the magi-lamp was extinguished, plunging the room into darkness.
The only light remaining was the soft glow of the moon streaming through the window.
"...I'll be solving your mysteries very soon."
Jin glanced briefly at the Moon before closing his eyes with a peaceful heart.
That night, it seemed Jin had a very good dream.