The shift happened in increments so small they could almost pass for accidents.
First, the Comfort Nest in the lab annexe became communal territory.
Gu Xun's designated spot on the bare laminate floor was still his penance, but the twins had started treating the invisible boundary like a suggestion.
Beiyu, the quiet one, began rolling off the plush memory foam in his sleep and landing squarely on Gu Xun's chest.
Beiyan, the biter, left half-chewed goldfish crackers in the crook of Gu Xun's arm like offerings to a favoured deity.
Lu Rin noticed everything.
He sat at his workstation, lavender eyes fixed on chromatographs that refused to resolve, pretending the warmth creeping into the room was just poor ventilation.
Friday afternoon, the twins were vibrating with bottled S-class energy.
Lu Rin didn't look up from his notes.
"Gu Xun. The pups need to run. You're getting soft around the edges. Take them to the restricted field. Wolf form."
It was delivered like a lab directive: clinical, efficient, designed to exhaust the boys and force the Alpha to burn calories Lu Rin privately refused to admit he still appreciated.
Gu Xun dropped his textbook as if it had insulted his mother.
"Wolf deployment: immediate and enthusiastic, Rin-rin."
The back sports field after hours was a fortress of privacy wards and motion sensors. Perfect.
Gu Xun knelt in the grass, golden eyes soft.
The shift rippled through him like liquid shadow.
Bones lengthened, muscles poured into new shape, fur unfurled in a cascade of midnight black shot through with molten gold.
The wolf that rose was obscene in size: shoulders level with a grown man's chest, paws the span of dinner plates, built to scatter entire rival packs without breaking stride.
But the scent was wrong, in the best possible way.
No crushing pine. No iron dominance.
Just warm resin, sun-heated earth, and the faint sweetness of fresh milk.
He smelled like safety.
The twins lost their tiny minds.
"Pony!" Beiyan shrieked, launching himself at the massive foreleg like it was playground equipment. He scrambled up the slope of Gu Xun's back, fists buried in thick fur, legs kicking triumphantly.
Beiyu circled once, suspicious nose twitching. Sniffed the flank. Sniffed again.
Then, satisfied that this enormous creature was indeed theirs, he climbed up behind his brother and settled like a king claiming a throne.
Gu Xun lowered his great head, ears flicked back in submission, and began a slow, deliberate circuit of the field.
Not a lope. Not a run.
A trot calibrated for four-year-old balance.
Beiyan yanked fur like reins and growled commands: "Faster! Left! Chase the moon!"
Beiyu sat regal and silent, one small hand pressed between Gu Xun's shoulder blades, occasionally leaning down to rub his cheek along the spine and mark ownership in ozone sparks.
They rode until the sky bruised purple.
When Gu Xun finally shifted back, human again and drenched in sweat, the twins collapsed against his bare chest in a tangle of limbs and exhausted giggles.
Later that night, the lab was quiet except for the hum of equipment.
Lu Rin ran a late sequence, shoulders stiff, pretending the room wasn't already scented with sleepy pups and devoted Alpha.
Gu Xun entered carrying both boys: freshly bathed, pyjama-clad, hair still damp.
"They're fed and clean, Rin-rin," he whispered. "But they won't settle without proper nesting."
Lu Rin's voice cut like winter glass. "Then nest them, Alpha. Some of us have work."
Gu Xun knelt, careful not to jostle. "They need Omega milk-scent for deep sleep. But they proposed a compromise."
Beiyan toddled straight to Lu Rin, arms up.
"Mommy nest."
Lu Rin lifted him without hesitation, settling the elder twin in his lap. A controlled wave of warm lotus-milk pheromones rolled out. Beiyan melted instantly, thumb in mouth, out cold.
Beiyu did not follow.
He walked past his mother's chair without a glance.
Stopped in front of the kneeling Gu Xun.
Stared up with those unnerving golden eyes: identical to his father's, but softer.
Then, deliberate as sunrise, Beiyu placed one tiny palm flat on Gu Xun's bare stomach, right over the ridged muscle that still flexed instinctively under the touch.
Gu Xun's breath stopped.
Beiyu climbed into his lap, curled into a tight ball, and burrowed his face beneath Gu Xun's collarbone.
Small arms wrapped as far as they could reach.
He exhaled a cloud of baby ozone and milk and slept.
Gu Xun didn't move.
Couldn't.
The former crown Alpha, breaker of packs, began to shake: silent, violent tremors of a man handed the world after five years in exile.
A single tear slid down his cheek and vanished into Beiyu's dark hair.
Across the room, Lu Rin watched over the rim of his monitor.
The sight punched straight through five years of armour.
Not for Gu Xun. Never for Gu Xun.
But for the boys: their effortless forgiveness, their instinctive trust in the father who had once failed them before they were born.
He shut the feeling down fast. Locked it behind ice.
"Gu Xun," he said, voice arctic. "If that child wakes because you so much as breathe wrong, you sleep in the hallway for a month."
Gu Xun nodded once, statue-still. "Understood. I'll photosynthesise if necessary."
Silence stretched.
Then Lu Rin spoke again, quieter. "The Lin girl. Name."
"Lin Yu'an," Gu Xun answered instantly, eyes never leaving Beiyu's sleeping face. "Kind. Strong. Crisp linen scent. I rejected the contract the same week your mark began to fade. Slept on the floor outside your apartment until security threatened arrest. Haven't touched another soul since the night I lost you."
Lu Rin's fingers tightened on his pen. No pheromone spike of deception. Just raw truth.
He stared at the solvent vial in his hand longer than necessary.
"Good boy," he muttered, barely audible.
Gu Xun's head snapped up, eyes wide and shining like he'd been knighted.
"Rin-rin—"
"I was speaking to Beiyan," Lu Rin cut in, frost snapping back into place. "He finished his shapes worksheet. Do not hallucinate praise, freshman."
But Gu Xun's smile could have powered the campus grid.
He knew what he'd heard.
He knew what it cost to say.
He bowed his head over his sleeping son, tears falling silent and steady.
The ice hadn't cracked.
Not yet.
But somewhere deep beneath the surface, something had shifted.
The thaw had begun: slow, inevitable, unstoppable.
Beiyu claims Gu Xun as his chosen nesting place for the first time. Lu Rin accidentally lets slip the first praise in five years: "Good boy," before yanking it back.
A late-night confrontation forces the truth of Gu Xun's abandonment out into the open: what really happened the night the lotus froze, shattering the cold veneer for the first time.