The air changed the farther they went.
Ren and Yuki had descended what felt like hours down the stone spiral staircase. There were no torches, no lights — only the dim glow of the symbols carved into the walls. And the deeper they walked, the more they felt it: the heartbeat of something ancient and awake.
"This place…" Yuki whispered, her voice echoing strangely. "It's not underground. It's beneath time."
Ren didn't respond. He was watching the carvings — flickering images repeating with each turn of the spiral.
Him.
Her.
The knife.
The shrine.
The moon.
Looped over and over in crude symbols, like a child's attempt to remember a nightmare.
System Tsuki: Core breach approaching.
Loop integrity below 20%.
Truth nodes will no longer remain hidden.
At the base of the stairs, the passage opened into a vast, circular chamber — utterly silent.
And at the center: a floating mirror, cracked straight down the middle.
Ren stepped forward. Yuki grabbed his hand.
"Wait."
He turned.
"This place… it feels like it's waiting for us."
Ren looked at the mirror again. It wasn't reflecting their images — it was showing a timeline. A spiraling constellation of memories, broken and bent. In the center, a glowing thread connected two constant points: Ren and Yuki.
"No matter how much changed," he whispered, "we always found each other."
"Or maybe," Yuki said softly, "we never left each other to begin with."
She stepped closer to the mirror. As she reached out — her fingers didn't touch glass.
They sank through.
Suddenly—
The chamber shattered.
Or maybe the illusion did.
Ren and Yuki were standing in a version of their classroom — only frozen mid-moment. Classmates hung mid-motion, chalk dust hovered in midair. Time had stopped completely.
And sitting at Ren's desk — smiling softly — was another Ren.
Older. Tired. Eyes like the moon.
"You made it," he said.
Ren froze. "Who are you?"
The other Ren stood. "I'm the one who stayed behind. The origin. The creator of Tsuki. The first loop."
Yuki's breath caught. "You…"
"I built the system," the original said. "Because you died. I couldn't handle it. So I copied everything I was and everything you were… into a loop that would keep trying until I got it right."
"You're not real," Ren said.
The original smiled faintly. "Neither are you. Not in the way you think."
Yuki stepped forward. "If you're the source — you can end this."
"I could," the original said. "But I won't."
"Why not?!"
"Because I love her too much."
The chamber cracked again — this time for real.
System Tsuki: Core fragmentation imminent.
Personality fragment 'Origin' resisting collapse.
Ren clenched his fists. "You're not love. You're obsession."
"I'm survival," the origin whispered. "I'm grief. You wanted to forget. I wanted to preserve."
Yuki touched Ren's shoulder. "We don't have time."
He nodded.
And without another word — he stepped forward and embraced his original self.
The memory flared white-hot — a clash of identity, grief, and truth.
And Tsuki, the system that watched but never warned, screamed.
Meanwhile…
Mio stood beneath the shrine gate as the red moon began to flicker.
"It's happening," Kaito said, breathing hard. "The core is folding."
Mio didn't look at him.
"They're merging."
Back in the heart of the loop, the mirror cracked completely.
And Ren opened his eyes.
Only now — there was no copy.
No system.
Just silence.
And Yuki, smiling through her tears.
"We're almost free."