The ceiling stain, Koichi kept staring at it. The sleeping quarters of Tabizuru—the thirty-room wooden lodging built in Akatsuguri—he could tell from the smell. The dry scent of wood. The wind from the ash plains audible from outside. The thin texture of the futon. All of it was something he had designed and built himself. He slowly raised his right hand toward the ceiling. The Building Master was quiet. It wasn't that it wasn't responding—it felt more like it wasn't there yet. Like something that had sunk to the bottom of a river, refusing to float back to the surface. He didn't feel afraid. He simply confirmed it. For now, it couldn't be used. That was all. (How many days have I been here?) The edges of his memory were still slightly hazy. Being pulled by Serika's hand at the top of the watchtower ladder. Ren quietly organizing the situation. Moving to a place beyond the residents' sight. After that point, the memory grew thin. He turned his gaze to the left. Serika was sleeping, half face-down on a chair. Her water-blue long hair hung from the chair's backrest, spreading loosely around her shoulders. The hair she must have tied up was half undone, and her pale purple eyes were closed. Her mouth was slightly open. Her sleeping face looked about three years younger than usual. Koichi didn't call out to her. A voice reached them from outside the window. "——Goods from the tributaries of the Riine River! Just arrived this morning!" A peddler's voice. From the direction of the sunny plaza—the market Koichi had built first. Followed by the sound of a cart rolling over stone pavement. The footsteps of a running child. Someone laughing in the distance. Even while Koichi was gone, Akatsuguri had kept moving. (Of course. What you build continues to stand even without you.) He knew that. In his head. But actually lying down and looking up at the ceiling while hearing the market's voice brought both relief and something else at the same time. That something he couldn't quite put into words kept moving in his chest for a while. His gaze stopped on the wall. It was a vine pattern. Fine leaf shapes carved in thin lines along the upper edge. The kind Serika had carved while she was at the Tsuzuri Fire Academy. She'd done it saying "it's too plain," before Koichi could stop her. At the time, he'd almost said "it's not in the design," but when Serika asked "Huh, you don't like it?"—Koichi couldn't say anything. It was a detail that wouldn't have been born from him alone. "——Mmn." There was a sound of movement on the chair. Serika opened her eyes. Her pale purple pupils weren't quite in focus yet. With a face still half in dreams, she looked vaguely toward Koichi. "Oh, you're awake." It was a leisurely voice. The serious moment ended abruptly. "……Yes, I'm awake." "Good." Serika yawned. She stretched both arms upward, and her spine made a soft cracking sound. "How many days have passed? I don't remember anything after a certain point either." "I don't know." "So you don't know that either." Serika stood up from the chair and walked toward the window. When she opened it, the morning air came in along with the louder sounds of the market. The wind rustled her water-blue hair. "The market's running." "I heard it." "Because it's a market Koichi made, it runs even without Koichi." After saying just that, Serika turned toward him. She stepped forward slightly, as if to check his complexion. The distance between them shortened. Her pale purple eyes looked at Koichi's face from close up. Koichi subtly averted his gaze. (Why is that embarrassing now?) Before worrying about his physical condition, a strange feeling came. He supposed it was proof of recovery. But acknowledging that felt wrong somehow. "Your complexion looks okay." "Thank you." "Can you sit up?" "Probably." He slowly raised his body. The world seemed to sway slightly, but it settled quickly. His neck was a bit stiff. That was all. --- Then the door was knocked on lightly. "——I'm coming in." Ren entered. His black hair was cut short with red highlights, and his golden eyes glanced at Koichi once before narrowing as if to assess his condition. In his hands were a folded cloth and a single small wooden board. "Has your consciousness returned?" "Yes." "What about the sensation of the magic element circuit?" "Still quiet. I don't know yet if I can use it." Ren nodded. There was no emotional fluctuation, but Koichi understood that meant "as expected." He entered the room and placed the wooden board on the floor. Several lines ran across the sand of the ash plains. A sketch. "I have a report. Last night, during a southern patrol, we captured one scout from the Steel Fang Corps——an armed group controlling the southern mining territories, a military faction with approximately twelve hundred combat personnel." Serika raised her voice. "You captured them?" "Yes. They were acting alone." "By yourself?" "The opponent was also alone." Serika started to say something, then stopped. "According to the scout's account," Ren pointed at the sketch, "the main force is scheduled to head toward Akatsuguri in three days. The advance route is to detour along the southwestern rift valley and approach the eastern defensive wall of Ash Wall Fortress. The minimum number is three hundred." "Three hundred." That number fell into the room. Serika traced the lines on the sketch with her finger, her lips pressing together slightly. "That's faster than I thought, or rather, more than I thought," she said quietly. "Yes. The scale is larger than initially estimated. ——There's one more thing." Ren's tone of voice changed slightly. Koichi sensed it. "The Curtain Veil Institute——ostensibly an organization engaged in trade mediation, but in reality an intelligence organization that plants operatives in various locations to buy and sell information and obstruct the rise of specific powers——we've confirmed that one of their operatives had infiltrated Akatsuguri." "……That merchant." Serika said in a low voice. "Yes. The merchant-like man who had been staying since the third night. He was counting the number of pillars outside the circle of the bonfire." Serika's expression changed. She bit her lip, and her gaze stopped on the sketch on the floor. It was Serika who had said "maybe he's doing it as a reference for business." Koichi had answered "that might be so" and returned to his calculations in his notebook. Neither of them had stopped it. "Last night, he disappeared. His luggage was left behind. When we checked the contents——" Ren flipped the wooden board over. Items were written on it. "Observation record scraps. Records of the number of facilities in Akatsuguri, population trends, frequency of Building Master usage. And——" Ren paused for just a beat. "One magic element furnace core stone." "A magic element furnace core stone……?" Serika's eyes widened. "Why would an operative have something like that in their luggage? That's more expensive than a jewel, right?" "It's not a jewel." "But it's expensive like a jewel." "……It's a rare ore that seals magic elements at high concentration. The properties are different." "But it's expensive either way." "It is." For just three seconds, the flow of the serious report completely stopped. Ren gave a light cough and brought the conversation back. Koichi listened to that moment while staring at the sketch on the floor. His eyes weren't on the map, but on his own palm. He looked at his right palm once more. Nothing happened. It remained quiet. (Three days, then.) --- After Ren left the room, only Koichi and Serika remained. Serika stood near the window, looking outside. The market's voice continued. "The buildings Koichi built are still running today." She said what she'd said before, once more. This time, in a slightly quieter voice. "The buildings continue to stand even without Koichi. But——" Serika closed her mouth. There was a pause. A moment where she was choosing her words. "But without Koichi, nothing new will be born." Koichi didn't respond. He turned his gaze outside the window. Beyond the defensive wall of Ash Wall Fortress, the skeleton of an incomplete watchtower stood against the sky. The gray wooden pillars piercing the gray sky, unchanged since yesterday morning. One tower was complete, one had stopped midway. (Three days won't be enough——) "I want to recalculate the remaining construction process for the defensive wall starting now." Serika turned around. For a moment, her expression almost became exasperated. But it stopped. Her expression changed quietly. She knew she couldn't laugh. She'd started to smile, then stopped. That was all Serika could do now. That Koichi would continue to move his mind like this, that it was the only way for him to process his emotions——Serika understood. So she didn't interrupt. She just kept looking at Koichi's face. A quiet moment fell over the room. Koichi took out his notebook. The incomplete process table spread open. The items not crossed out with lines. He held a pencil but didn't move it, staring at the blank space in the sketch. "One person won't be enough in three days." His voice was small. Close to confirming a fact. There was no emotional explanation whatsoever. But Serika accurately received the density of those words. "I understand." That was all. Neither added anything more. They didn't need to, so they didn't. Koichi stood up and opened the door. "I'll call Ren." --- The three of them gathered around the sketch. "Please design the defenses." Koichi said to Ren. He omitted emotional explanations. He didn't apologize. He simply asked. Ren looked at Koichi. Just for a moment. Then he turned to the sketch. "Understood." His golden eyes moved across the map. His finger traced the lines. "Prioritize the eastern defensive wall, the watchtowers can be built simultaneously depending on materials. Adjust the resident traffic flow so it doesn't intersect with building material transport, using the northern passage——" Serika cut in. "Use magic element detection to excavate buried materials, like we did yesterday." "That would help. Priority would be——" "Deep areas on the eastern side, choose the ones with high density. That worked best last time." "Fill the hole in the eastern wall in three days, build two watchtowers. Secure evacuation routes for residents. This is the minimum." Ren looked at Koichi. "Depending on the Building Master's recovery——" "I'll make it in time." Ren nodded once more. This time, for longer. At that moment, Serika looked up from the sketch. "Hey, what about calling this thing in the middle the Bond Tower?" "We're not at the naming stage yet." "But having a name would——" "A name affects morale." Silence. Koichi looked at Ren. He looked twice, slowly. Ren continued tracing the sketch with his finger, his expression unchanged. It was unclear whether he was even aware that he'd made a point. Serika leaned forward. "See!?" "……We'll decide later." "Ugh! Let's decide now!" "Serika, we need to confirm the process first——" "But you agreed too!" "I only mentioned the morale aspect." "That's the same thing!" Ren quietly but firmly cut Serika off. "We need to check the inventory of materials on the eastern side tonight. After that, I'll listen to the naming discussion," he said. Serika said "……Okay, but I'm definitely asking about it later" and backed down. Koichi watched that moment from the corner of his eye. Before, Serika's words would have floated between the two of them. Now, Ren cut Serika off, and Serika yielded. Within the sparseness of words, the three of them were facing the same direction. Koichi was aware of that. --- Night fell. The three of them stood in Akatsuguri's central plaza. The sky was cloudy, with few stars. The wind thinly carried the sand of the a