Breath caught in his throat. Sweat clung to his skin. His vision blurred, flickered, and then stabilized.

Ren Yoru sat bolt upright in a creaking bunk, his lungs dragging in air like they hadn’t tasted oxygen in years.

The room was dim. Faint, flickering lights buzzed overhead. Peeling metal walls. A single desk in the corner stacked with ration packs and data slates. Familiar.

Too familiar.

"No way..." he whispered.

He stumbled out of bed, knocking over a cracked water canister. The liquid splashed across the floor, but he didn't care. He gripped the edge of the desk and stared at the digital calendar etched into the corner screen.

June 21, 2279.

Seven years before the Citadel mission. Before Ayane died. Before Juno betrayed him. Before everything burned.

He was back.

A laugh escaped him—sharp and cracked and full of disbelief. "Echo Protocol... you actually worked."

[ECHO PROTOCOL: TEMPORAL ECHELON SYNCHRONIZER v0.1 ONLINE. SYSTEM SYNC: 98.4%. STABILIZATION COMPLETE.]

[WARNING: PRIMARY DIRECTIVE LOCKED. INTERFERENCE REQUIRED TO PROCEED.]

Ren leaned against the wall and slid down until he was sitting, breath shallow.

He remembered the pain. The betrayal. The cold steel through his chest.

He remembered Ayane's face.

He wouldn’t let it happen again.

Fifteen minutes later, Ren stood beneath the rusted pipework of the orphan training hall—a massive dome-like chamber buried under Neo-Tokyo's old sewer infrastructure. Kids of all sizes jogged around faded tracks, practicing basic drills, their movements clumsy and uncoordinated.

It was like watching ghosts. Ghosts that didn’t know they were dead yet.

A sharp buzz echoed from the wall-mounted cameras. One of them rotated slowly—then stopped. Ren stared at it longer than he should have.

He felt it. Like static behind his eyes.

He was being watched.

"Yoru! You alive or just haunted?" a voice called.

Ren turned, heart catching.

Ayane.

Younger. Her silver eyes full of mischief, not trauma. Her black hair in tight braids. She jogged toward him, sweat on her brow, laughing.

"Don’t tell me you overslept again. If you make us miss points, I swear I’m hacking your toothbrush."

Ren stared. He couldn’t help it.

Ayane blinked. "What? Do I have grease on my face?"

He forced a chuckle. "No. Just... good to see you."

She tilted her head. "You’re acting weird."

"Yeah, well... guess I missed your voice."

A flash of something unreadable crossed her expression. A half-second too long. Then it was gone.

She grinned. "Okay, weirdo. Come on. Instructors'll mark us late."

As she trotted off, Ren followed—steps heavy.

He’d forgotten what it felt like to see her smile. Like really, truly smile. It almost hurt more than her dying.

[SYSTEM NOTE: INTERFERENCE NODE IDENTIFIED: SUBJECT AYANE.] [PROXIMITY: 12m. CATALYTIC POTENTIAL: HIGH.]

He swallowed hard. "System... what do I have to change?"

[DIRECTIVE LOCKED UNTIL NODE ALTERATION INITIATES TEMPORAL CASCADE.]

[TIP: FIRST VARIANCE CREATES DOMINO.]

Drills began with standard obstacle tests. Ren scaled walls, dashed under metal beams, dodged stun-bots with ease. More than ease—muscle memory from his past life kicked in, and his body moved like a veteran among trainees.

"Damn, Yoru," Ayane panted, catching up beside him. "Did someone swap your legs with a servitor?"

"Just... had a good night," he said, flashing a tired smile.

Instructors started whispering. One jotted notes onto a slate. Ren tried to dial it back.

Midway through the sim, something in the environment flickered. Glitched.

A security drone shimmered, then reset. It shouldn't have been there. Not this early in the program.

[SYSTEM ALERT: ECHO STABILITY THREATENED. TEMPORAL VARIANCE: 1.2%. SYSTEM ENHANCEMENTS TEMPORARILY LOCKED.]

[ERROR: HOST CANNOT EXCEED ACCEPTABLE LIMIT WITHOUT STABILIZING THE NODE.]

He frowned. "You're telling me I'm too good?"

[CORRECT. CHOICE: SUPPRESS. GUIDE. OR CHANGE NODE.]

Ren's eyes landed on Ayane. Still lagging behind. Breathing hard. Trying. Just like back then. Except last time, she never got the chance to grow.

In the last life, he’d kept her behind—safe, protected. But that only made her easy to break.

Suppress. Guide. Or change.

He turned to her, offering his hand mid-run. "Want to beat me? Start now."

She blinked. "What?"

"I'll train you. Nights. Extra runs. Real drills. No instructors. Just us."

She hesitated, eyes wide.

"Unless you're scared."

Ayane looked up at him, then slowly nodded. "No. Just... weird. This feels like we’ve said this before."

His chest tightened. "Maybe we have. Just didn’t mean it until now."

[SYSTEM RESPONSE: TEMPORAL NODE ALTERED. VARIANCE +3.7%. CATALYST TRIGGERED.]

[DOMINO EFFECT INITIATED. MONITOR CLOSELY.]

A strange pulse ran through Ren's bones. The timeline shifted. He felt it like a breath held too long finally exhaled.

He had started it.

One choice.

The first ripple.

A buzz echoed overhead. Propaganda screens flickered on above the dome—a smiling Overseer broadcasting with artificial warmth:

"Through obedience, strength. Through loyalty, survival."

Ren looked up at the screen. Then down at Ayane, who was catching her breath beside him.

He made a silent vow:

This time, you won't die for a war you never chose.

And far above them, in the silent towers of Neo-Tokyo, a file updated itself automatically on a forgotten server:

SUBJECT 021: REN YORU
STATUS: DIVERGENCE DETECTED. INITIATE WATCH PROTOCOL.