The growl outside intensified, vibrating through the thin wood of the door. Primo's heart hammered against his ribs like a trapped bird. He gripped the kitchen knife—a simple stainless steel blade that suddenly felt pathetic—and looked around his small apartment.
Block the door? Or the window?
He was on the second floor. A jump was possible, but he didn't know what was waiting for him on the pavement below. He began to back away from the door, his eyes darting toward his backpack. I need water. My phone. My—
CRACK.
His heel caught on a stack of books he'd left on the floor. Balance betrayed him. He tumbled backward, landing hard on his tailbone. The sound of his fall was like a dinner bell.
The scratching on the other side of the door turned into a frantic, high-speed clawing. Primo scrambled to his feet, ignoring the sharp sting in his lower back. He lunged for his bag, but he was too late.
The bottom panel of the door splintered inward. A shape burst through the hole with terrifying speed—a dog, or what used to be one. It was the size of a mountain lion, its fur matted with dark, foul-smelling slime. It launched itself at his throat.
"Gah!" Primo grabbed the nearest thing—a wooden kitchen chair—and shoved it upward.
The beast slammed into the chair, the force throwing Primo back onto the floor. Now, he was pinned. The mutated dog was a snarling mess of teeth and snapping jaws just inches from his face, held back only by the wooden rungs of the chair.
Adrenaline surged, hot and electric. His vision narrowed. His left hand strained to keep the chair between him and the beast, while his right hand frantically slapped at the floor, searching for the weapon he'd dropped.
His fingers closed around the handle of the knife.
Without a second thought, he drove the blade into the side of the creature. Then again. And again. He didn't count the stabs. He didn't hear his own ragged breathing. He only stopped when the heavy weight finally slumped, sliding sideways off the chair in a wet heap.
Primo lay there for a long moment, staring at the ceiling, waiting for his heart to slow down. When he finally sat up, he saw the hole in his door. Silence had returned to the hallway, but the air felt heavy.
He looked at the carcass. It was a Golden Retriever, but warped—larger, with claws that looked like blackened bone. He noticed a thick trail of blood leading from the hallway into his room; the dog had been dragging an injured hind leg. That was the dragging sound.
"I got lucky," he whispered, wiping sweat from his eyes. "It was already hurt."
As the dog's blood pooled on the linoleum, something caught the light. In the center of the mess, near the chest wound he had opened, sat a rough, rounded crystal. It was the size of a small marble, glowing with a dull, visceral red.
He picked it up. It was warm—unnaturally warm—and felt like it was vibrating. He wiped it clean on his shirt, fascinated.
Is this it? A Gene Core?
Before he could process the thought, a sharp knock echoed from the ruined door.
"Is someone in there? Is anyone alive?" A man's voice called out.
The sudden sound sent a jolt of pure panic through Primo. In a moment of sheer, clumsy instinct—like a child caught with a handful of stolen candy—he shoved the red marble into his mouth to hide it.
He went to answer, but as he opened his mouth to speak, he instinctively swallowed. The hard, warm marble slid down his throat.
"I'm here!" he yelled, his voice cracking.
"Fuck! Is he an idiot?" a girl's voice hissed from the hallway, sounding irritated.
A louder knock followed. "Open up! We need to move, now!"
Primo scrambled to the door and pulled it open. Standing there were two of his neighbors: a man in his late 40s who looked like an off-duty cop in civilian clothes, gripping a handgun, and a girl roughly his age or slightly younger, holding a baseball bat.
"Hurry, follow us," the man ordered.
Primo stood there, blinking, his mind still on the marble currently settling in his stomach. The man didn't wait for a reply; he grabbed Primo's arm and hauled him out of the room. They ducked into an apartment three doors down, the man locking the deadbolt with a soft click.
"What—" Primo started to protest, but the man's hand clamped firmly over his mouth.
The man pointed toward the door.
Seconds later, the sound arrived. A chorus of rapid, heavy footsteps flooded the hallway they had just left. There wasn't just one. There were dozens. Low growls and the sound of claws scraping against the walls echoed through the door.
The man and the girl gripped their weapons, their faces pale and set in grim determination. Primo stood frozen between them, his hand over his stomach.
Deep inside him, he felt a sudden, blooming heat. The marble was starting to burn.
The tension in the room was suffocating. The neighbors stood like statues, their eyes locked on the door as the sounds of his apartment being torn apart echoed down the hall.
Primo, however, was fighting a different battle entirely.
As the heavy furniture in his room was smashed by the pack outside, a dull, pulsing heat began to spread from his stomach into his limbs. At first, it felt like a mild ache, the kind of soreness that follows an intense workout. But within seconds, the heat spiked into a white-hot fire.
The pain migrated from his muscles to his head with dizzying speed. A sudden, searing sensation erupted in his ear canals and nostrils, as if someone had poured molten lead directly into his skull. It felt like his very DNA was being rewired, the "essence" of the marble he had swallowed violently forcing its way into his system.
"Mmmph!"
Primo's eyes bulged. He instinctively tried to scream, but the neighbor's heavy hand was still clamped over his mouth, muffling the sound into a low, guttural vibration.
His hands flew to his head, clutching his ears as if he could squeeze the pain out. His vision blurred, and tears pricked at the corners of his eyes. The burning in his nose was so sharp he expected to see smoke. It was unbearable—a raw, agonizing transformation that threatened to snap his consciousness.
Yet, even through the haze of torture, a primal instinct for survival kept him grounded. He looked at the man's grim face and the girl's white knuckles on the bat. If he screamed, if he made even a single loud noise, the pack of mutated beasts in the hallway would turn their attention to this door.
He bit down on the man's palm, not enough to draw blood, but enough to use the physical resistance to keep from vocalizing. He forced himself to endure, his body trembling violently against the wall, sweat pouring down his face as he waited for the S-Rank skill to finish its work.
Inside his mind, a silent notification flickered, unseen by the others.
[Assimilation in progress...]
[Target: Feral Canine Core (Low Grade)]
[Status: 40%... 60%...]
The sounds of scratching moved closer to their door, sniffing at the gap in the frame. Primo held his breath, the fire in his ears finally beginning to dull into a strange, heightened ringing.