Park Eunji received the vacancy report at 6:43 AM.
The annex building in the fourth district had gone quiet. Her operator had run three sweep passes through the block overnight and the fourth-floor readings had dropped to baseline — the residential ambient of an uninhabited apartment, blood-will at sediment level, the decay signature of recent occupation without current presence. The high-amplitude readings she'd been tracking for three weeks, the specific dual-state frequency signature she'd built an operational file around, were gone.
She set the report on her desk and looked at it.
They'd been watching the investigation coverage. Of course they had. The preliminary article at 7 AM yesterday, the full piece at 11 PM, the committee hearing this morning. They knew the investigation was tightening. They knew Shin Youngjae's cooperation was public. They knew the BTD's operational authorization was going to be formally reviewed within seventy-two hours.
They'd moved between the full article and the sweep window.
She looked at the grid map. The operator's last confirmed read had been from the southern tributary in the fourth district, before the vacancy. The secondary-location dispersal pattern from that address had seven probable options within the transit time they'd have had.
She pulled out her pencil and marked the seven.
Seven locations. She'd eliminate three of them on transit-time grounds alone. The remaining four would require sweep passes, and the sweep passes required operational authorization, and the BTD's operational authorization window was narrowing by the hour as the IIC investigation moved through its preliminary phase.
She had thirty-six hours. Maybe less.
The grid work was technical and verifiable. A sweep was reading, not action — it didn't require operational authorization it didn't have. The authorization question came when she moved on what she found. She wasn't at that question yet.
She'd done more with less.
The cases file on her desk held the operational profile she'd been building since the Anyang corridor signal — the dual-state frequency signature, the healing output parameters, the junction-extraction work her operators had been reading in the tributary network. Whoever this practitioner was, he wasn't alone anymore. The Mun Jaehyun testimony had confirmed a community of practitioners with blood-arts development. The network was larger than the BTD's original assessment.
She understood, abstractly, that the investigation was changing what she was authorized to do. She understood what that meant for the larger operation.
She would run the grid.
She would do the work that was available to do before the window closed.
---
The secondary location's tributary channel ran under the building's north wall. Smaller than the annex's channel — a tertiary branch, quiet, the kind that accumulated sediment slowly and read thin at range. Seonghwa had spent the first two hours after arriving learning its depth and direction.
He was learning it now in the same way he'd learned every channel since the Undercity settlement: slow passes, low amplitude, the old-way extension that treated the Blood Sense not as a probe but as a presence in the water, moving at the water's pace. Elder Goh had called it *reading without asking* — the way blood cooperated with blood when neither was trying to take something from the other.
The channel had been running for fifty years. The sediment in it held the ordinary accumulation of a mid-rise residential block: family cooking smells that had settled into blood-will as daily biological events, the childhood injury frequencies of three generations of apartment kids, the particular residue that long-term illness left in a blood-will profile when a practitioner spent enough time with it. Nothing extraordinary. Just the city.
He sat with it until it felt like his.
Then he went to see how the foundation session was going.
---
Nam Chohee had arrived at 7:30 AM. She'd come in scrubs with her night-shift quality still present and the particular alertness of someone who had been mentally preparing for something on the commute and was now here and in the work.
She sat across from Jisoo with the bone blade between them.
"She can feel you already," Jisoo said. "Your reception axis. She's been reading it since you came in."
Nam Chohee looked at the blade. Not the way a new person looked at an unusual object — the way a nurse looked at a patient whose chart she hadn't read yet. Assessing. Waiting for more information before committing to a read.
"What does it feel like," she said. "From her side."
Jisoo bridged. A pause. "She says it feels like — double-axis blood-will in a high-reception state, which is the most developed innate profile she's encountered in someone without formal training in two decades." She pressed. "She says: your blood is already doing the old-way orientation. You've been teaching it to do this for years without knowing what you were teaching."
Nam Chohee looked at her hands on the table.
"The patients," she said. "I thought I was reading cortisol. Blood pressure. Things that the vital signs weren't catching fast enough." She paused. "The ones who tanked faster than the numbers said they should — I caught three of them in the last year. No one could explain how."
"Blood-will," Jisoo said. "The deterioration frequency reads before the vitals move."
"That's what I was reading."
"Yes."
She sat with that for a moment. Then she straightened, the hospital-efficiency movement that appeared when she'd processed something and moved to the next thing. "What does the foundation training actually involve."
Jisoo explained it. Seonghwa stood in the doorway and listened.
The old-way foundation wasn't technique — that was what Elder Goh had taken three weeks to explain and what Seonghwa still didn't fully understand as an explanation, only as a practice. The technique came after. The foundation was orientation: learning to treat the blood as a partner in the circulation rather than a mechanism to be managed. The blood was already doing what it did. The practitioner's job was to stop fighting it and start listening.
"How long," Nam Chohee said.
"Depends on the baseline," Jisoo said. "Yours is strong. Maybe weeks before the blood starts cooperating with the awareness rather than running beneath it." She pressed the blade. "Serin says: for someone with your reception-axis development, the foundation may be faster than standard. Your blood has been trying to do this for years. It's waiting for permission."
Nam Chohee looked at the blade again.
"Tell her I'm giving it permission," she said.
---
The first session ran for forty minutes. Seonghwa observed from the doorway until the foundation work's initial phase settled into its rhythm, then went back to the tributary channel read.
Mirae came in at 11 AM with the monitoring notebook and updated him on Jisoo's treatment parameters from last night. The hemoglobin response had been better than expected given the drop — the longer session had stabilized the rate of decline. Not reversed. Stabilized.
"The trend," he said.
"Still down," she said. "But the slope is flatter this week than last week." She wrote. "The daily treatment is maintaining the window, right? But it's not pushing the baseline up." She looked at the notebook. "I've been thinking about whether the foundation work is affecting the degradation rate. If Nam Chohee develops the third-way healing output and we can run bilateral sessions — two practitioners generating the healing frequency simultaneously at Jisoo's blood-will network—"
"We don't know if bilateral sessions are possible."
"We don't know they're not." She closed the notebook. "I'll add it to the open-question list." She paused. "Baek Minho. The completion tomorrow."
"He'll be at Hwang Jungsook's building by 10 AM. I meet him there."
"I want to come."
"You don't have to."
"I know I don't have to." She looked at him the way she looked at him when she was making a clinical determination. "The completion protocol — you and Baek Minho have run it four times together. You've refined the monitoring approach each time. I want to see the Dongdaemun completion specifically because it's the final extraction and the foundational layer will be complete and I want to understand what that state looks like clinically before Baek Minho starts the direct-transmission work." She paused. "I need the data."
"Come," he said.
She went back to her notebook.
---
Hyunwoo returned at 2 PM.
He came in and sat at the table and looked at the wall for a moment. Not the formal-register quiet he'd been in last night. Something that had processed overnight and come out the other side. He'd been running operational work since 8 AM — the blood-will contact with the broker network's remaining clean members, the circuit-breaking that had to happen when an intelligence product had been compromised, the specific labor of finding out which of your contacts had known Kwon Seyoung well enough that they might have been secondary exposure points.
He'd been thorough, Seonghwa guessed. He was always thorough. Thoroughness was the form his grief took.
"Kwon Seyoung," he said.
"You found him."
"I found him." He paused. "He's at the independent investigative counsel's intake office in Mapo. Turning over everything he had. The full intelligence product from three years." He paused. "His son was released from BTD custody at 10 AM this morning. Shin pulled the hold before he finished his own intake deposition." He paused. "The coercion contract is void. The leverage is gone."
Seonghwa looked at him.
"He's cooperating because—"
"Because the coercion contract was explicitly documented in Shin's files," Hyunwoo said. "The moment Shin's files became evidence in the investigation, Seyoung's cooperation with the BTD was on the record. Voluntary cooperation with the IIC is better for him legally than waiting to be called as a compelled witness." He paused. "Also because his son is out and he's been in a three-year cage and he wants the door open." He paused. "And because he's angry."
"At Shin."
"At the whole structure that made it possible for a BTD commander to walk up to a broker with a family and say *your son or your network.*" He paused. "He's angry in a very specific and useful way." He paused. "The things he turned over — they're going to be good for the investigation."
"Good," Seonghwa said.
A silence.
"I should have known," Hyunwoo said. Not to him specifically. "He has a kid. The kid is an unregistered practitioner. I knew that. I should have flagged him as a coercion risk and verified his status before I let him anywhere near network location data." He paused. "I didn't. I've been running this network for seven years and I got careless with the security protocol." He paused. "I won't again."
"Hyunwoo."
He looked at him.
"You couldn't have prevented everything," Seonghwa said.
"No," he said. "But I could have prevented this particular thing." He didn't say it like self-recrimination. He said it like a professional updating their standard operating procedure after a failure. "I'll rebuild from the clean contacts. It'll take time." He paused. "We have time. The IIC investigation is running. Eunji's operation is under review. The pressure window for the BTD to make a move before the investigation constrains them is—"
He stopped.
"What," Seonghwa said.
"The Dongdaemun completion is tomorrow," Hyunwoo said. "The BTD has a window. Forty-eight hours before the investigation formally freezes their active operations." He paused. "Eunji ran a sweep grid last night on the fourth district. She knows the annex is empty." He paused. "She'll have moved to the grid pattern for likely secondary locations." He looked at Seonghwa. "How long before she narrows to this district."
Jisoo spoke from the inner room. She'd been in passive-contact since the foundation session ended.
"She's already in this district," she said. "She's running the grid. Four blocks north."
The secondary location's tributary channel ran under the building's north wall.
Seonghwa looked at the wall.
"Tomorrow morning," he said. "We run the Dongdaemun completion and we get clear fast. One hour maximum at Hwang Jungsook's building."
Nobody disagreed.
