It took Jin and his team a full two days to modify the boat.
First, they installed a cockpit and rigged the rudder with wire cables for steering. Next, they added levers to independently adjust the output of the left and right Air Jets. As a safety precaution to keep debris from being sucked into the machinery, they protected the intakes with wire mesh.
Then, prompted by a remark from Eira—
"Jin, we can't back up like this, can we?"
—they took the first prototype they had built and mounted it backward on the bow to function as a reverse engine. Finally, after reinforcing the wooden hull with bronze fittings, the powerboat was complete.
"Ho, this is marvelous!"
Paerova Sondvik, who was still staying in the village, shouted with satisfaction after taking a test ride on the finished vessel.
"Well done. Jin, Eira, Kachea."
From around this time, Paerova began referring to him simply as Jin. Jin felt relieved, as the man’s wariness toward him finally seemed to be fading.
"If we mass-produce boats of this design, water transport will thrive!"
In the Mercana Principality, towns and villages had long developed along the Great Noshina River. However, despite the lack of waterfalls along its length, water transport hadn't actually flourished as much as one might expect.
The main deterrent was the sheer effort required to navigate upstream. While traveling downstream was as simple as riding the current, returning necessitated either immense manual labor or a power source. As a developing nation, the usage rate of the existing roads remained much higher.
However, while the powerboat Jin and his team developed had a higher initial crafting cost, its maintenance expenses were comparable to a normal boat. It could travel upstream at a speed only slightly slower than a carriage, and on the return trip, it could travel nearly twice as fast.
"Alright, let's try mass-producing them."
Furthermore, since the design didn't utilize any complex, specialized technology, it was well-suited for production. Even so, the pace would likely be limited to about one boat every five days.
＊ ＊ ＊
Upon returning to Rofon, the three were given a special reward of 50,000 Toll each—equivalent to roughly 500,000 yen.
"...It feels like a dream."
The amount easily exceeded her monthly allowance of 10,000 Toll. Kachea felt bashful, constantly insisting she hadn't done enough to earn such a sum.
"That's not true. You've been a huge help with all the calculations," Jin reassured her.
"Is that... really true?"
"It is."
Jin explained that if he built things based on intuition alone, they often required extensive rework. The biggest problem, however, was that he frequently ended up creating items that were impossible for anyone else to replicate.
"I think... I might understand that, in a way."
"Yeah."
Having engaged in manufacturing here, there was something Jin had come to realize clearly as well.
"The importance of returning to one's roots... remembering why we make things, and understanding what makes a product truly 'reproducible'..."
Particularly the last point—consideration for mass production—was something Jin hadn't focused on in a long time. He had rediscovered a different kind of fulfillment, one distinct from the thrill of creating a unique masterpiece.
"Hey, Jin, now that we've got some extra income, let's head out for a meal."
"Oh, sure."
Jin had been lost in thought in his room, but he stood up and replied when Eira called out to him from the hallway. When he opened the door, Kachea was standing there beside her. The two women seemed to have become quite close.
"It's still bright out."
"It's summer, after all. Besides, I know a nice little place. I'm sure you'll like it, Jin."
"I'm looking forward to it, then."
Jin and Kachea followed at a quick pace as Eira strode confidently through the streets. She headed toward an alley near the edge of town and led them to a small shop.
"Welcome."
The shop's construction was strikingly reminiscent of Japanese architecture.
"I'm Eira Shiata, I have a reservation."
"Yes, we have been expecting you. Right this way, we have a private room prepared."
The clerk greeted them politely and led them toward the back.
"They have private rooms here," Eira explained. "You have to take off your shoes, which is a bit of a chore, but it’s a relaxing place."
"Taking off our shoes?"
"That's right. Here, take them off. The clerk will put them in a shoe box for you."
Eira pointed toward a wooden slatted mat.
"How interesting," Kachea said, being the first to slip off her shoes and step up into the shop. Jin and Eira followed her.
"This way, please."
They passed through a corridor with wooden flooring and across a covered walkway. The inner garden was much more expansive than it appeared from the outside. The three were shown into a private room that felt like a detached annex.
"Shall I bring the food immediately?"
"Yeah, please."
"Understood. Then, please, make yourselves comfortable."
The clerk bowed and withdrew.
The room was about the size of six tatami mats, featuring a wooden floor, a low table, and several zabuton cushions.
"This feels somewhat nostalgic," Jin murmured.
"I thought you might say that," Eira replied, sitting down on a zabuton and crossing her legs.
Kachea turned a little red and tried to imitate her, but Jin stopped her.
"Kachea, you don't have to force yourself. Sitting sideways or duck sitting is fine."
"What is... duck sitting?"
"Like this."
Jin demonstrated. Duck sitting involves sitting with your bottom on the floor while your legs are tucked beside your thighs. It was also known as "girl sitting" or "petan-style sitting."
"Ouch, ouch... Do you get it?"
Jin, whose body was quite stiff, found holding a duck sit for even a short time to be an ordeal.
"Yes, like this, right?"
Kachea, however, managed it with ease.
"Ho ho, like this?" Eira tried to copy her as well. It seemed uncomfortable for her, too. "...I like my way better after all," she said, shifting back to a cross-legged position.
Jin sat cross-legged as well.
"Thank you for waiting."
Just then, the food was brought in. After setting down the dishes for the three of them, the clerk placed a handbell on the table.
"If you need anything or wish to place an additional order, please ring this bell."
With that, the clerk departed.
"Alright, let's toast."
Eira poured drinks into Jin and Kachea's glasses. The liquid was transparent with a slight yellow tint and carried a fruity aroma.
"A toast to our team's success!"
"Cheers!"
They toasted and took a sip. And then...
"...Is this alcohol?" Kachea, who had expected juice, was taken aback.
"...Ginjo sake?" Jin, on the other hand, was surprised for an entirely different reason.