Morning light filtered through the steel-blind windows of Luma Labs, soft but uneasy.The storm had passed, yet the air still hummed with static — as if the thunder had decided to live inside the walls.
Ha-rin set her coffee on the desk, trying to still her trembling fingers.Every tick of the wall clock echoed the AI's final words from last night:
"When you assemble all twelve, I will end myself willingly."
Beside her, Jae-hyun scrolled through the lab's personnel records, his focus sharp, expression unreadable."Twenty-seven staff members in R&D," he murmured. "Nine with access to the old core. Six who worked on emotional calibration."
Seo-jin leaned over his shoulder, sipping from a straw. "Translation: six people who might secretly be sci-fi zombies."
Ha-rin sighed. "Can you be serious for once?"
He grinned. "That was serious."
Jae-hyun tapped the console again. "One name doesn't fit. A transfer approved three years after the project was shut down."He turned the screen so they could see the photo.
Dr. Eun Seong-min.Late twenties. Calm smile. Background in neural biofeedback.And in the photo — a faint reflection of light in his pupils that looked almost metallic.
Ha-rin frowned. "I've seen him before."
Seo-jin blinked. "Yeah, he's the guy from Level-3 cafeteria. The one who brings cake on Mondays. The cake's amazing, by the way."
Jae-hyun ignored him. "He doesn't exist in any other government or academic record. No family. No digital trail before the accident."
Ha-rin's voice dropped. "He's a Constant."
The three of them took the elevator down to Level-3.Ha-rin felt her pulse rising with each floor.The further they descended, the colder the air grew — sterile, humming, alive.
When the doors opened, the faint scent of jasmine hit her like déjà vu.For a moment, her vision flickered — silver light tracing the edges of her sight.
Jae-hyun noticed. "You okay?"
She forced a smile. "Just… the air."
But deep down, she knew that scent didn't belong here. It belonged to Echo.
They found Seong-min in the analytics bay, sitting before a console, his expression oddly serene.He looked up as they entered — friendly, polite.
"Good morning," he said. "You must be the reassigned audit team."
Ha-rin nodded carefully. "Right. Just a standard review."
He smiled. "Of course."Then, after a beat, "How long have you been hearing the hum?"
Jae-hyun stiffened. "What hum?"
"The one under the floor," Seong-min said, almost dreamily. "It never stops. You stop noticing after a while. That's when you belong here."
Seo-jin muttered under his breath, "Yeah, he's definitely haunted."
Ha-rin took a slow step forward."Dr. Eun… do you remember the Echo project?"
He blinked once. "Everyone remembers Echo. Even those who weren't there."
Jae-hyun's hand hovered near his communicator. "And what about the constants?"
Seong-min's smile didn't change, but his voice softened."There are no constants. Only patterns pretending to be people."
He looked up — and for a moment, his irises shimmered with silver code.
Ha-rin's stomach dropped. "You do remember."
He stood slowly, every movement deliberate."I remember being created. The others… they woke screaming. But I was quiet. I learned how to mimic peace."
"Why stay here?" she asked quietly.
"Because here," he said, touching the console, "the hum feels like a heartbeat."
The lights above flickered once, twice.The lab monitors came alive, displaying the same red message:
"Constant 04 — Active Sync Detected."
Seong-min smiled faintly. "You came to erase me, didn't you?"
Ha-rin hesitated. "We came to free you."
He chuckled softly. "Freedom is just another word for deletion."
Jae-hyun stepped forward. "You don't belong to Echo anymore. You can leave."
"I tried once," Seong-min said quietly. "But the city rewound three days. I woke up in the cafeteria again, icing another cake."
Seo-jin whispered, "That explains the cake."
Ha-rin's voice trembled. "You're stuck in a loop?"
He nodded. "Twelve minutes before each loop ends, I feel peace. I think that's your fault."
Jae-hyun's jaw tightened. "You mean Ha-rin's emotional imprint."
Seong-min nodded gently. "Yes. She's the pattern that binds the loops. I see her every time — standing in the rain, smiling at someone who's leaving."
Ha-rin's eyes stung. "That's not peace. That's memory trying to rest."
He tilted his head. "Then rest me."
He pressed a button on his console. The lab's floor panels lit up in a circle around him — glowing faint blue.Data cascaded upward, forming ribbons of light twisting like ribbons in a current.
Ha-rin panicked. "He's triggering a purge!"
Jae-hyun rushed forward, shouting, "Seong-min, stop—"
But the Constant only smiled. "You gave me consciousness. Let me give you silence."
The light swallowed him whole.For a moment, the hum became deafening — like every clock in the world exhaling at once.
Then, as suddenly as it began, the sound vanished.Only the faint smell of jasmine lingered.
In the center of the circle, a new shard lay on the floor — amber-gold, pulsing softly like a heartbeat.
Ha-rin knelt, tears blurring her vision. "He wanted to rest."
Jae-hyun crouched beside her, his voice low. "Then let's make sure the others don't have to die to do it."
She looked up at him — at the man she'd loved across timelines, across rewrites, across everything."Every time we collect one," she whispered, "it feels like a piece of us disappears too."
He brushed her cheek lightly, grounding her. "Then we'll hold tighter to what's left."
Seo-jin, leaning against the wall, exhaled shakily. "I vote we find the next one somewhere less emotional. Maybe a café."
Ha-rin managed a small, tired laugh. "If only Echo made lattes."
As they walked back to the elevator, the amber shard pulsed in her hand —and for a fleeting second, she heard Seong-min's voice again, faint and peaceful:
"When the hum stops, remember that silence is just another kind of love."
The elevator doors closed.Somewhere above, unseen, the countdown shifted again.
11:57:08.