I Was Reincarnated as the Prince in a Villainess Story, so I’ll Use My Cheat Knowledge to Create a Noble Lady Harem and Make Them All Happy - 20

Chapter 20: The Quiet Truth Inside the Bottle

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Three days had passed since Reina’s departure, and it was around noon when the sealed bottle arrived in the royal capital.

The bottle, gently placed atop the desk, swayed quietly, revealing a faintly cloudy hue in its water. When Valis carefully removed the tightly sealed stopper, a subtle scent drifted up—heavy and metallic, like iron. The liquid, which should have been clear, had a viscous texture as it slowly trickled down the inner walls.

Valis exhaled softly as his gaze followed the movement toward the bottom of the bottle.

“Just as I thought…”

Lukewarm water. Stagnant circulation. Unclear cleaning frequency. The conditions aligned too perfectly.

Legionella. The name of that bacterium surfaced from his distant memory. It was back when Valis had worked for the city’s water department. There had been a string of pneumonia cases at a senior facility’s public bath. The cause traced back to bacterial growth inside the water storage tanks.

That said, this was another world. There wasn’t even any certainty that the concept of “microbes” existed here. There were no culturing methods, no microscopes. And yet, the “phenomenon” Reina had described was eerily similar to what he had once encountered.

The coughing in the affected village was concentrated among children and the elderly. When questioned, they admitted that the bathwater was rarely replaced, the stones at the bottom were slimy, and the heating was insufficient.

In contrast, in the royal capital’s public baths, there had not been a single case of this kind in years. The reason was simple: more people, daily cleaning, and frequent replacement of the water. A difference of scale and frequency. In other words, a difference in cleaning and circulation.

That seemed to be the logical conclusion. But this was another world, one where remote territories were still rife with unknowns—magical beasts and worse. Hasty assumptions could be dangerous, and future caution would be essential.

“…I can’t be certain, but I can see what needs to be done.”

Valis resealed the bottle and pulled out a set of prepared materials from the lower drawer of the filing cabinet. A hand-drawn diagram, a short written explanation, and a fresh sheet of enchanted stationery for sealing. He intended to send three instructions back with the messenger.

First — Replace the bathwater every day.

Second — Scrub the bottom stones each morning with a brush.

Third — Use the village’s stock of quicklime, dissolve it in water to make slaked lime, and sprinkle it on the stones during cleaning.

After cleaning, drain the water the next morning and refill with fresh water. This was to be repeated until the symptoms subsided. However, lime was finite. Once used, it would eventually run out. And that meant the capital would have to supply more.

Valis took from his drawer a silver-engraved magical document tool—the Solitaria Scripta. He infused the center of the open parchment with mana, and faint letters began to appear.

“I, Valis Alveria, Crown Prince of Alveria, hereby pledge to the following village a periodic replenishment of slaked lime for the purpose of maintaining bathhouse sanitation, to be supplied from the royal capital’s reserves.”

He signed and stamped it. The moment the letters were inscribed, the device glowed softly. Its light served as both record and proof.

“Good.”

He sealed the document together with the letter for the envoy. With the diagram attached to the instructions, he ordered the envoy to explain the procedure directly to the village bath attendant.

Truthfully, he would never know if “bacteria” had truly been the culprit. But as a countermeasure, this was the best he could do—and, in a way, he felt relief that it was a problem solvable through his own knowledge. He was genuinely thankful it hadn’t turned out to be the beginning of some unknown monster or demon incursion.

Still…

Valis stared at the sealed document again, deep in thought. The issue was the lime supply.

For several years, Valis had been promoting the use of lime around the royal capital—for sanitation and as agricultural fertilizer. In particular, it had become essential for cultivating a certain strategic crop now grown in large quantities across the kingdom.

However, mass distribution was still hindered by two obstacles: supply and transport. Alveria was a landlocked nation with no coastline. Its sources of limestone were limited, and it relied heavily on importing seashells and other marine materials from coastal nations.

The nearest such country was the Kingdom of Beltea. Although the refugee crisis there had somewhat eased, instability remained, and large-scale trade had yet to resume. The kingdom still depended on small-scale private imports conducted by merchants.

Moreover, producing lime required intense heat.

Archive Arts was unreliable for maintaining the necessary high temperature and consistent output, making it unsuitable for industrial-scale lime kilns. Craftsmen capable of Spirit Arts, such as Elves and Dwarves, were rare in Alveria, as neither race had settlements within the kingdom’s borders. Hence, steady supply continued to depend on foreign imports.

Prices rose, logistics suffered, and the material rarely reached rural villages.

“…I thought I could handle it through Archive Arts somehow, but the deeper I study, the more I realize the weight of this world’s dependence on Spirit Arts for daily life.”

Alveria, like other nations, benefited from Spirit Arts—but to develop something new, one needed exceptionally skilled practitioners capable of withstanding the strain. He had even drafted a budget to recruit foreign students on a large scale, but races proficient in Spirit Arts—Elves and Dwarves—were reluctant to leave their own settlements, whose communities were strong and self-contained.

Moreover, Spirit Arts were inherently regional. Their effectiveness was often tied to the local spirits they commanded. Even spirits of the same attribute could vary by region, sometimes weakening when removed from their native land. Still, wishing for what one didn’t have would get him nowhere.

He would build systems that minimized sickness as much as possible. That was Valis’s duty.

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Two more weeks passed.

According to regular reports, the number of coughing children and elderly had visibly decreased, and the management of the bathhouses was gradually stabilizing. Milia’s healing magic had also been effective. Elderly patients once bedridden in the infirmary were now able to walk out into the garden.

The village children, too, were laughing again, running about the square. Valis had worried they might grow afraid of bathing, but that fear proved unfounded. In fact, the children eagerly helped clean the bathhouse every day. For them, perhaps cleaning the tubs wasn’t so different from playing in the water.

Valis set the report down and gazed out the window. The sky above the capital was clear, and blue banners fluttered quietly over the castle gates. At that moment, a waiting attendant spoke softly.

“Your Highness, Reina-sama and Milia-sama have returned.”

“…I see.”

Valis exhaled deeply and stood. This time, he would go greet them properly.

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“We’re back! Ahhh, I’m exhausted!”

With a bright voice and outstretched arms, Milia entered the office with Reina and Valis. A light sheen of sweat glistened on her forehead, her cheeks flushed as though brushed with rouge. Yet her expression was radiant. There was no trace left of the pale, anxious girl who had once rushed out of the capital.

“Milia, show some restraint. You’re in His Highness’s presence.”

Reina followed, her attire a unified ensemble of blue armor and dress—a battle gown of sorts. She had brushed off the dust of travel but kept her posture perfectly composed, though faint shadows of fatigue lingered under her eyes. She had likely worked even harder than Milia, managing both logistics and command.

“Oh, come on, it’s fine! We visited like ten villages, you know? On foot! Every single one of them was on narrow paths even the knights’ horses couldn’t take!”

“In parallel with the knights’ deployment, I also oversaw the bath attendants’ training and the sealing procedures.”

“…And after all that, you still look flawless. That’s so unfair, Reina.”

Milia grumbled, pouting slightly as she walked up to Valis and promptly clung to his arm.

“So, Valis, since you’re a prince and all… You are going to soothe the weariness of your beloved princesses who worked so hard for you, right?”

Her tone was light and teasing, but beneath it lingered a faint, genuine plea. It made Valis’s arm go slack for a moment. Reina narrowed her eyes quietly, casting a chastising glance at Milia’s back.

“It’s fine to lean on His Highness, but perhaps save such behavior for later, once we’ve settled down.”

“Eh, but come on~ It was bath-related this time! Isn’t relaxing in the bath the proper way to recover from it?”

With a soft laugh, Milia pressed her cheek even closer to Valis’s arm.

“…Huh?”

Valis blinked, caught off guard and before he could recover, the other woman moved soundlessly.

“Now that you mention it, Your Highness, we don’t recall receiving any reward in the form of a bath for our efforts.”

Reina murmured. Gone was the composed lady who had just scolded Milia. Reina now slid her arm smoothly around Valis’s other side, her gaze steady and warm—not overly provocative, but carrying unmistakable heat.

“I could, of course, prepare the finest royal bath for the two of you anytime, but… That’s not what you’re implying, is it?”

He said timidly and their answer came in perfect unison.

“Obviously!”

“Obviously, Your Highness~♡”

Even their voices harmonized perfectly.

Wait. Are they actually saying they want me to bathe with both of them at the same time…?

With two beautiful princesses gazing up at him with sparkling eyes, Valis could do nothing but steel himself for what was to come.

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