The tax inspector arrived on the fourth day, which was either very fast or very slow depending on how seriously Karashima took unclaimed hillside real estate.
Ryu was on the roof frame when he saw the man coming up the path. Not because the man was remarkable, he was small, soft, and wearing the specific expression of someone who had been given authority slightly too large for his personality, but because of the two guards walking behind him with the bored competence of professionals who expected no resistance and were prepared to manufacture some if necessary.
"Goro," Ryu said.
"I see them."
"Keep working."
Goro kept working. Kenji kept carrying stone. Fumiko, who was sorting dried herbs in the northeast corner, looked up, assessed the situation with one glance, and went back to her sorting with the focused calm of someone who had decided this was not her problem until told otherwise.
Ryu climbed down from the roof frame.
The inspector stopped at the edge of the flat ground and looked at the building with the expression of a man who had expected a hole in the ground and found something inconveniently solid.
"Mizushima Ryu?" He read the name from a paper he was holding, mispronouncing both syllables.
"Close enough," Ryu said.
"I am Prefect Daizo, representing the interests of Lord Karashima in the matter of unauthorized construction on territory adjacent to district water resources." He unrolled the paper further. It was a long paper. He had clearly enjoyed writing it. "You are required to present documentation of land claim, construction permit, and water usage license before work may continue."
Ryu looked at him. "This is unclaimed land."
"All land in this district is claimed by virtue of its proximity to water resources under the Karashima Charter of the Third Reign."
"Show me the Charter."
Daizo blinked. This was apparently not the expected response. The guards shifted slightly, recalibrating for a situation that had become mildly more complex than anticipated.
"The Charter is a matter of noble record," Daizo said.
"Meaning you don't have a copy."
"Meaning it is not carried in the field."
"Then I'll need to see it before I can respond formally to any claim based on it." Ryu kept his voice the way he kept his hands on a difficult fitting: steady, patient, no excess force. "I'm happy to pause construction pending documentation review. How long will that take?"
Daizo's paper rustled. "Procurement of noble records requires formal application through the district office, which processes applications on the first and third market day of each month."
"Today is the second market day."
A pause. "Yes."
"So the earliest I could receive documentation is in approximately twelve days."
The paper rustled again. Daizo was a man being outmaneuvered by arithmetic, which was visibly painful for him. "Construction must cease pending resolution."
"I'm building on unclaimed land with no documentation of any claim currently in my possession. Ceasing construction based on an unverified verbal assertion would expose me to material losses." Ryu tilted his head slightly. "Is Lord Karashima prepared to compensate those losses while the documentation is procured?"
From the northeast corner, entirely without looking up from her herbs, Fumiko made a small sound that might have been a laugh converted at the last moment into a cough.
Daizo's left eye did something involuntary. "I will report your non-compliance."
"Please do. And when you report, mention that I'm building a public bathhouse, not a water extraction facility. No water is being diverted from any existing supply. I'm using a geothermal vent." Ryu gestured at the steam, which was performing helpfully on cue. "You're welcome to have the vent inspected if Lord Karashima has questions about the geology."
There was a long silence in which Daizo clearly wanted to do something authoritative and couldn't locate the legal mechanism for it.
He rolled his paper back up. It took longer than it should have because his hands weren't entirely steady.
"You will be hearing from the district office," he said.
"I look forward to it. Can I offer you water for the walk back? I have a good well source." Ryu kept his expression helpful. "Clean water. You understand."
Daizo left. The guards followed, slightly faster than was dignified.
Goro set down his chisel and looked at Ryu with an expression that had moved, over four days, from professional disapproval to something approaching unwilling respect.
"That bought you twelve days," he said.
"Eleven," Ryu said. "I want the roof on in eleven."
They made eight.
It was the roof that did it, the practical momentum of a structure becoming a building, of walls acquiring a ceiling and a ceiling acquiring purpose. Goro stopped questioning the timeline somewhere around day six and started racing it. Kenji, who had not spoken more than fourteen words in total, turned out to have an instinctive grasp of load distribution that Ryu recognized as genuine talent wrapped in silence.
Fumiko filled every horizontal surface not currently being built on with drying herbs, which meant the construction site smelled, improbably, of cedar and lavender and something she called yuhari that Ryu couldn't identify but that the back of his sinuses recognized as deeply, ancestrally correct.
Aine came on day five with three women from the village who needed work and had heard something was happening on Fuchi no Yama.
She introduced them with the efficiency of a woman filing paperwork. "Misa, former laundress, noble house. Hana, herbalist's apprentice, relevant experience. Tomoe, no relevant experience, but she's large and she doesn't panic."
Ryu looked at Tomoe, who was indeed large and who was looking at the half-built bathhouse with the calm assessment of someone deciding whether a thing was worth her time.
"Can you lift that beam?" Ryu pointed.
Tomoe lifted the beam.
"Welcome aboard," Ryu said.
Aine stayed after the others had been assigned tasks. She walked the floor plan with the measuring precision of someone who had lived in houses where the floor plan mattered, running her fingers along the limestone and checking the level of the channels Ryu had cut for water routing.
"The channels slope correctly," she said, with the tone of someone who had expected to find fault.
"They need to. The drainage has to move by gravity. I don't have pumps."
"You don't have pumps," she repeated. She crouched over the main channel, tracing the line of it toward the vent. "How does the water get from the vent to the bath chamber?"
"Copper pipe. I'm fabricating it from fittings I have and raw copper stock Fumiko sourced from the metalsmith in lower Mizutani." He crouched beside her. "The vent feeds a collection basin here, the basin feeds the main soaking chamber here, overflow routes through the drainage channel and disperses in the soil downslope. The temperature moderates naturally over the run length, so the soaking chamber sits at a usable temperature without any regulation mechanism."
Aine was quiet for a moment.
"You designed this in your head," she said.
"In the dirt first. Then my head."
She stood. "It's going to work."
"Yes."
"That's the problem." She looked at the walls, solid and pale in the afternoon light. "Things that work attract attention. Karashima's inspector was fast. When this opens and word travels, the next visit won't be a man with a paper."
Ryu stood too. "I know."
"Do you have a plan for that?"
He was about to answer when the floor moved.
Not the shiver he'd felt on the first day, the polite rhythmic knock of something curious and cautious. This was a full heave, brief and localized, centered on the northeast corner, where the limestone floor cracked along a seam and a section approximately one meter square tilted upward like a trapdoor being pushed from below.
Everyone in the building went still.
The section tilted further. Something small, blue, and extremely put-out pushed itself through the gap and sat on the edge of the cracked stone with the dignity of someone who had intended to use the door and found the door had been built on top of them.
She was roughly the height of a ten-year-old child but the proportions were wrong in small precise ways that added up to unmistakably not human. Blue-grey skin. Two horns curving back from her temples, short and smooth, the color of old copper. Hair that was either black or very dark blue depending on the light, and eyes that were solid amber with no visible white.
She was also, and Ryu registered this as a separate and significant data point, visibly furious.
She pointed at the drainage channel. Then at Ryu. Then she said something in a language he didn't know, at a speed and volume that communicated its meaning perfectly without translation.
Fumiko made the cough-laugh sound again.
Aine stepped forward. "Fuchizo," she said quietly.
The creature's amber eyes moved to Aine and the stream of words stopped. A brief, assessing silence.
Then the creature looked back at Ryu, pointed at the drainage channel again, and repeated one word. Slowly, this time. Clearly. As if speaking to someone who was going to need the extra effort.
"Atsui," she said.
Ryu understood that one. His father had said it every summer in the workshop, reaching for a cold drink.
Hot.
He looked at the drainage channel. Looked at the crack in the floor. Looked at where his drain line ran, downslope, through the soil, directly toward whatever was below.
"I'm draining hot water into your house," he said.
The creature stared at him.
"That's. I'm sorry. That was not intended." He pulled out his tape measure. "I can reroute the drain. Two days."
Another silence. The amber eyes moved from the tape measure to his face with an expression that was recalibrating rapidly from outrage toward something more complicated.
She said another word. Pointed at the bath chamber. Then at herself. Then held up what appeared to be, from her perspective, a question.
"She wants to know," Aine said carefully, "if she can use it."
Ryu looked at his floor plan. Looked at the bath chamber, sized for forty humans. Looked at the creature sitting on his cracked floor with hot water damage to her ceiling and copper horns catching the afternoon light.
"Same rate as everyone else," he said.
Fumiko dropped her herbs.