The assignment took four days.
Four days of Rion's precise handwriting filling the left margins and Kael's faster looser script filling the right, four days of arguments conducted in the careful quiet voices of people surrounded by other people who could not know what they were actually arguing about, four days of a shared laptop screen and tea that went cold and the particular tension of two people sitting close enough to be aware of every small movement the other made.
The topic was mythological marine biology. The irony was not lost on either of them.
They worked in the campus library mostly, at the table in the east reading room that had become by unspoken agreement their table, the one with the good lamp and the clear sightline to the door and enough space between them that the space could be maintained if either of them wanted to maintain it. Neither of them always wanted to.
On the second day Kael had leaned across to correct something Rion had written and his shoulder had pressed briefly against Rion's and neither of them had moved away and the sentence had taken considerably longer to correct than it should have.
On the third day Rion had fallen asleep at the table for approximately eleven minutes and Kael had looked at him for approximately ten of those minutes and had not examined why too closely.
On the fourth day they had finished the assignment at eleven at night and submitted it through the university portal and sat back in their chairs and looked at the ceiling in the particular silence of two people who had been using a task as an excuse to be in the same room and had just run out of tasks.
"Done," Kael said, to the ceiling.
"Done," Rion confirmed, to his portion of the ceiling.
A comfortable silence settled over them, warm and unhurried, the kind that had not existed between them two weeks ago and existed now without either of them having made a conscious decision to build it.
"You wrote the bioluminescence section better than I expected," Kael said.
"You expected it to be poor."
"I expected it to be technically correct and emotionally inaccessible." He tilted his head sideways to look at Rion. "It was technically correct and surprisingly not inaccessible."
Rion turned his head to look back at him. The lamp between them threw warm light across both their faces. "You wrote the cultural mythology section better than I expected," he said.
"What did you expect?"
"Myohyang propaganda dressed as academic analysis."
Kael laughed. A real one this time, unguarded, arriving without being caught first, and Rion watched it happen with the expression of someone filing it under something important.
"Fair," Kael said, when the laugh had settled. He did not look away. Neither did Rion. The lamp hummed quietly between them. "What would you have written if it had not been an assignment?"
"About what."
"About bioluminescence." His voice had shifted, not dramatically, not to anything that could be named too precisely, just slightly warmer, slightly more deliberate. "You wrote about it like it was a language. Like the light meant something specific."
Rion was quiet for a moment. Around them the library breathed its late night quiet, nearly empty at this hour, a librarian somewhere in the back working through a returns cart with the soft rhythm of someone who had been doing this long enough not to think about it anymore.
"It does," Rion said. "Mean something specific." He held Kael's gaze with the steadiness that was his natural mode but had something beneath it now, something less armored. "Different patterns mean different things. Greetings. Warning. Distress." A pause. "There is one that has no direct translation into spoken language. The elders describe it as the light a merfolk emits when they are in the presence of something their body recognizes before their mind does."
The lamp hummed.
Kael's amber eyes held him without blinking. "And does that happen often."
"No," Rion said. "It is considered quite rare."
"Hm." Kael leaned his cheek against his hand, elbow on the table, watching Rion with the expression he wore when he was thinking several things simultaneously and had chosen to present only the surface of one of them. "And if I asked whether it had happened recently."
"I would say that is a very direct question."
"I am a very direct person."
"You are a person who uses directness strategically," Rion said, with the precision of someone who had been studying the difference for two weeks. "Which is not the same thing."
Something sparked in Kael's eyes, pleased and sharp and warm all at once. "You have been paying attention."
"I pay attention to everything."
"To me specifically."
"To everything," Rion said again, with exactly enough composure to make it unconvincing and exactly enough awareness of that to make it deliberate.
Kael smiled. Not the smirk, not the dangerous predator smile, not the performance of confidence. Something quieter. Something that lived closer to the actual face beneath all of it. "Rion."
"Kael."
"The light." He said it simply, no pressure behind it, the question offered rather than demanded. "Has it happened recently?"
Rion looked at him for a long moment. At the white silver hair and the amber eyes and the smile that was real and the eleven minutes he had watched him sleep and the shoulder that had not moved away and the four days that had felt like something they were building rather than something they were enduring.
"The elders," he said, carefully and precisely and with full awareness of what he was doing, "would say that the question is already an answer."
The silence that followed was the warmest one yet.
Kael held his gaze for another moment, that quiet real smile still present, something in his eyes that was soft in a way his court bearing rarely permitted. Then he straightened slowly, picked up his bag, and stood. He looked down at Rion with an expression that held everything they had not said and was entirely comfortable holding it.
"Come on," he said. "I will walk you home."
"I do not need to walk home."
"I know." He was already moving toward the door. "I want to."
Rion looked at his back for a moment. Then he picked up his bag and followed, and did not examine the warmth in his chest too directly because examining things sometimes made them smaller and this particular thing he wanted to leave at full size.
They walked out into the Seoul night side by side, close enough that their arms occasionally brushed, neither of them moving apart when they did.
---
The assignment was returned six days later.
It appeared in their shared university portal with a grade that made Kael stare at his phone for a long moment and then hold it up without a word for Rion to see. Full marks. The first in the class. Below the grade a single line of feedback in the professor's characteristically economical style:
*Exceptional anatomical accuracy. Source material appears to be primary. Request meeting — Prof. Oh.*
Rion read it twice. Then he looked up from the phone slowly.
"Primary source material," Kael said.
"Yes."
"He knows the information did not come from any published text."
"He knows it came from someone who has lived inside the anatomy," Rion said quietly. "Which means he knows what we are. Or suspects it accurately enough that the distinction does not matter."
They were in the campus courtyard, late afternoon, the autumn light going golden across the stone paths. Other students moved around them unconcerned, belonging entirely to the ordinary version of the world. Kael looked at the message again. Then at the building across the courtyard where Professor Oh's office occupied the third floor corner room with the window that faced the gate.
Professor Oh, who had been at this university for eleven years according to the faculty page. Professor Oh, who had assigned this specific topic to this specific research pair. Professor Oh, who had warm unhurried eyes and ink stained hands and a three streets from campus that he ran on evenings and weekends.
Rion had arrived at it first. He could see it on his face the moment the thought completed itself, that particular stillness that was Rion's version of alarm.
"Oh," Kael said. Not a sound of realization. A name.
"Oh Minho," Rion said.
The professor who had assigned them to each other on the first day of class. The owner who had confirmed each of them to the other. The man with the warm smile and the ancient eyes who had been two steps ahead of every move they had made since they arrived.
Not a neutral party. Never a neutral party.
A position. Placed precisely. Waiting.
"He put us together," Kael said, very quietly. "On the first day. The partner assignments."
"They were not random," Rion said. The courtyard was ordinary around them, golden and oblivious. "Nothing he has done has been random."
"The assignment topic."
"Chosen."
"The feedback requesting a meeting."
"An invitation," Rion said. "Or a summons. I am not yet certain of the difference."
Kael looked at the third floor window. The light was on. A figure moved behind the glass, unhurried, with the particular ease of someone who had been expecting this moment and had arranged a comfortable chair for it.
"He has been watching us since before we arrived," Kael said.
"Since before we arrived," Rion confirmed.
"Which means he knew we were coming."
"Which means someone told him." Rion finally looked away from the window and met Kael's eyes, and in his silver gaze was the cold clear quality of deep water that had stopped being still. "Or he has been watching for this specific moment for considerably longer than our arrival."
The autumn light went golden across the courtyard stones. Inside the third floor office the figure behind the glass went still, as though aware of being observed, and then, slowly, as though offering something deliberate rather than incidental, turned to face the window.
Oh Minho looked down at them from the third floor with his warm unhurried expression and his ink stained hands folded behind his back, and even from this distance, even through glass and afternoon light and the ordinary busy world between them, the smile on his face was the smile of someone who had been waiting three hundred years for exactly this and found the wait entirely worthwhile.
He raised one hand. Not a wave. A greeting between equals who have finally arrived at the same table.
Then he turned back into his office and was gone.
Kael and Rion stood in the courtyard in the golden afternoon and said nothing for a long moment.
Then Kael said, very quietly, "We are going to need Sera."
"And Councillor Seo," Rion said. "He arrives tomorrow."
"Good." Kael looked at the empty window one more time. Then he looked at Rion, and beneath the sharp focused readiness of someone who had just identified a threat there was something else, something warm that the threat had not displaced, that the threat in fact had made more clear by contrast. "Whatever he wants from us. Whatever this is." He paused. "We face it the same direction."
Rion looked at him. At the amber eyes that held both fire and steadiness, at the prince who had shown him three pages of his forefather's journal and trusted him with the weight of them.
"The same direction," he said.
Above them the third floor window reflected the autumn sky, empty and golden and full of everything that was coming.