A few days before Jin set off for the Klein Kingdom.
In Asunt, the capital of the Kingdom of Egerea.
A hot air balloon with a golden envelope appeared in the sky overhead. The words "Nostalgia" were written across the envelope in large, bold letters, asserting its affiliation with absolute clarity, regardless of its artistic merit.
The kingdom ritter order, which had already studied the hot air balloon Jin had gifted them and constructed two identical models, immediately moved to intercept the golden craft. As they drew near, a voice called out from the golden balloon.
"I am Elena, a diplomat for Nostalgia. I have brought a gift for your nation. I request permission to land."
The voice was transmitted via a spell that gave sound directionality using wind magic, allowing it to reach a specific person at a distance. This technique, commonly used before the Great Magic War, was known as an "Aco-tube."
The Kingdom of Egerea was the nation furthest from Nostalgia's base. Since Elena required neither food nor sleep, she had decided to visit the most distant country first. Incidentally, the Kingdom of Elias was not a target for this dehumidifier donation, as its climate and dietary habits were significantly different; she planned to provide them with the technology whenever a suitable opportunity arose in the future.
Flanked by the Egerean hot air balloons, Elena landed in the courtyard of Asunt Castle. Twenty members of the Royal Ritter Order surrounded her, hands on their hilts, though they did not draw their swords.
Elena felt a faint, wry smile tugging at her inside. She remembered well that during the era of the Unifilar, this very castle had been attacked using hot air balloons.
"It is a pleasure to meet you. I am Elena, a diplomat for Nostalgia."
Elena introduced herself once more. A single knight stepped forward to meet her.
"Welcome, Lady Elena. I am Bruno Thales Bright, vice-captain of the Royal Ritter Order. May I assume that your business today is to present us with these 'dehumidifiers'?"
Elena smiled radiantly. At that smile, several of the knights were captivated, their stern expressions softening into grins.
"Yes, that is correct. Might I ask you to introduce me to the official representative or the person in charge?"
"Most certainly. Kelichdore, the minister of magic, and William, the minister of internal affairs, shall attend to you."
Once Bruno had spoken, the other knights turned on their heels and departed. Elena took a small parcel in hand and followed Bruno across the courtyard—which still bore the scars of the Golem Party incident—toward the Guest House, a building located to the left of the Outer Palace.
Elena was ushered into a room that appeared to be the Guest House's large conference hall. With two royal magi-ritters in attendance, the explanation began.
"By lowering the temperature, we cause condensation to form, extract that moisture, and then return the air to its original temperature to remove the humidity. That is the operating principle. Do you understand?"
The attendees looked perplexed by the concise summary.
"Er... well, the mechanism itself seems simple enough. I wonder, would we be able to manufacture them as well?"
"Yes. By all means, please try to make them yourselves," Elena replied with a gentle smile. "The extracted moisture will collect inside, so please be sure to drain it periodically. Are there any questions?"
"Why does condensation occur when the temperature is lowered?" Kelichdore asked.
Elena put on a troubled expression. "It would be impossible to explain that in such a short time. For now, please simply accept that it is a natural phenomenon."
However, Elena could see a clear look of dissatisfaction clouding Kelichdore's face.
"The upper limit of the amount of water vapor that air can contain changes depending on the air temperature. This is called the saturated water vapor capacity. When the temperature is high, it can hold a great deal; when the temperature is low, it cannot hold as much. How about that? Now that I have explained it, more questions have cropped up, haven't they? It is a matter of lacking the fundamental knowledge. That is why I said it would be impossible to explain in a short time."
Elena's red eyes held no hint of disdain, and Kelichdore found himself unable to press the matter further.
"You have seen water droplets form on the outside of a glass containing cold water, have you not? That is due to this same principle," Elena added kindly. This supplementary explanation seemed to satisfy him.
"Are there any other matters?"
Everyone remained silent. Perhaps they had given up.
"In that case, I shall take my leave."
Elena stood up with a polite bow. Once again, Bruno escorted her back to her hot air balloon.
There was a figure watching her from a distance. It was the Third Prince, Ernest. He tilted his head occasionally as he watched Elena.
"Prince? Is something the matter?" Lyla, the prince's personal maid, asked curiously.
"Hmm... That is a strange automata. She feels different in nature from the ones Jin makes."
Lyla was startled. "Pardon?"
"I mean that automata named Elena. She's different from Reiko-chan. And yet, there's something similar about them, too. But they're different. Hmm..."
"U-Um, is that girl an automata?"
"Eh? She is, isn't she? Can't you tell by looking at her?"
"N-No, I can't tell at all...!"
The prince had instinctively realized that Elena was an automata. Besides him, Kelichdore was likely the only other person who had realized her true nature. Not a single one of the knights watching her from a short distance away had noticed.
After that, Elena headed for the Klein Kingdom. The reaction there was much the same. She was received by Chancellor Powell, Minister of Industry Delite, and Viscount Bernardo Nefra Foster, the commander of the Second Ritter Order. They, too, were unable to grasp the principles of the dehumidifier she explained.
"I shall take my leave then."
Elena offered her greetings and prepared to depart. Just as she was about to board the hot air balloon, her eyes widened for a moment.
(Blue hair... An automata of Adriana Barbora Tsetse?)
She saw Princess Lieschen watching from a distance, accompanied by her wet nurse automata, Tia. A murky emotion momentarily threatened to rise in Elena's heart at the sight of that blue hair, but it was quickly suppressed.
The hot air balloon then rose into the sky.
The Kingdom of Franz was similar.
(...All these staring eyes are quite annoying...)
Furthermore, the discipline of the knights and soldiers was low, and the representative's ability to understand was poor.
(The future of this country looks bleak...)
And in the Celuroa Kingdom, there were even movements to secretly abduct Elena. Just as Elena finished her business and was about to return to the hot air balloon, a voice cried out.
"Lady Elena! A golem has gone berserk! It's dangerous, please run!"
It was a blatant, staged "accident." Looking over, she saw two golems, built for combat, charging toward her at high speed. One of them was on a course that would hit Elena directly—and if she dodged, it would slam into the hot air balloon.
(What shall I do...)
Currently, Elena had been de-tuned so that her output was only equivalent to a human's. However, her reaction speed and her combat techniques remained intact. She was programmed to self-destruct if her control core was ever at risk of being analyzed, so the danger of her secrets being stolen was low, but self-defense was still necessary.
She had no more time to think. Elena moved to intercept the charging golem. Just before it reached her, she shifted her body a single step to the right and swept the golem's leg. It was the same principle as a forward foot sweep in judo.
The golem's upper body, unable to keep up with the shift in its center of gravity, easily lost its balance and pitched forward. Since there was a risk it would crash into the balloon if left alone, Elena grabbed the golem's left arm and used her own body weight to redirect it. Even though she weighed less than half as much as the golem, it was enough to change the direction of its momentum while it was off-balance.
Releasing the arm, Elena quickly vacated the spot. The second berserk golem was closing in, and it slammed directly into the first one she had redirected. The two became entangled and went rolling across the ground in a heap.
"I shall leave the rest to you. Well then, everyone, good day."
Elena quickly untied the mooring lines, hopped into the hot air balloon, and activated her fire magic. The envelope swelled, and the gondola lifted off. Since she was no longer carrying a heavy cargo of dehumidifiers, the ascent was rapid.
While the soldiers watched in dazed silence, Elena continued to gain altitude.
(...I truly cannot tell if humans are wise or foolish...)
Carrying such thoughts, Elena piloted the hot air balloon back toward headquarters.