The brand behind Marvis's left ear throbbed with every beat of her heart.
It was a small thing—a circle bisected by a single vertical line, no larger than a copper coin—but it might as well have been a chain binding her to the bottom of the world. She had received it on her tenth birthday, the day the caste assessors had come to the sanitation hub and pricked her finger with a silver lancet.
"O-Negative," the assessor had announced, his voice flat with boredom. "Universal."
Her mother had wept. Her father had gone very still, his face draining of color. Later that night, he had explained what it meant.
"You are the foundation," he had said, his hand on her small shoulder. "Without O-Negatives, the high castes would die. Their bodies cannot accept any other type in an emergency. You are the universal donor. You are precious."
He had smiled then, a fragile thing.
"But they will never let you forget that you are also worthless."
Now, six years later, Marvis stood in the filtration chamber of Sector Seven's main processing hub, scrubbing coagulated blood from a grate with a stiff-bristled brush. The iron smell was so thick it clung to her clothes, her hair, the inside of her nostrils. She had long since stopped noticing it.
Around her, other O-Negatives worked in silence. Twelve of them, all wearing the same grey uniforms, all bearing the same brand behind their ears. They moved like automatons—scrub, rinse, move to the next grate, scrub, rinse, repeat. The shift was twelve hours. The pay was enough to keep her and Mira in bread and thin broth. The alternative was the Processing Hubs, where O-Negatives were kept in sterile pods and drained systematically until their bodies gave out.
She had seen the Processing Hubs once, on a delivery run. She still had nightmares.
"Vane."
The foreman's voice cut through the rhythmic scrape of brushes. Marvis looked up to find him standing at the chamber's entrance—a stout man with a face like old leather and a brand just like hers. The only difference was his uniform: a grey jacket with a single red stripe, marking him as a supervisor.
"You're needed in the sorting office," he said, jerking his thumb over his shoulder.
Marvis's hands tightened on the brush. The sorting office was where allocation orders were processed—where O-Negatives were told which sectors they would be assigned to, which duties, which hours. It was rarely good news.
"What for?" she asked.
The foreman's expression didn't change. "Just go."
She set the brush down, wiped her hands on her uniform, and followed him out of the chamber. The corridors of the processing hub were narrow, lit by the same flickering lumen-globes that plagued the lower wards. They passed other O-Negatives—some scrubbing, some hauling containers of filtered blood, some sitting slumped against walls during their brief breaks. No one made eye contact.
The sorting office was a small room at the end of a long corridor. Two clerks sat behind a counter, their brands hidden by high collars—B-Positives, Marvis guessed, based on the pale blue trim on their uniforms. They looked up when she entered, and one of them slid a sheet of paper across the counter.
"Reassignment," the clerk said. "Effective immediately. You're to report to Textile House Seven."
Marvis's blood ran cold.
Textile houses were where A-Positives worked. High-caste labor, clean work, good pay. Mira had been assigned to Textile House Seven six months ago, and it had been the brightest spot in their otherwise grim existence.
But O-Negatives didn't get reassigned to textile houses. O-Negatives got reassigned to worse filtration hubs, or to the blood farms, or to the Processing Hubs.
She picked up the paper and read it. Her name was there, clear as day: Marvis Vane, O-Negative, Sector Seven Filtration Hub. Reassigned to Textile House Seven, Sector Four.
"This is a mistake," she said, her voice steadier than she felt. "I'm O-Negative. I'm not qualified for textile work."
The second clerk shrugged. "The order came from Enforcement. You want to argue with them, be my guest."
Enforcement. The Blood Market's enforcers. Commander Jeff's people.
Marvis's mind raced. This wasn't a promotion. This was something else. Something she didn't understand.
"What about my sister?" she asked. "Mira Vane. She's assigned to Textile House Seven. A-Positive."
The clerks exchanged a glance. The first one tapped at a console, and a screen flickered to life.
"Mira Vane," he read, "A-Positive. Textile House Seven. Status: Active."
Relief flooded through her, brief and fragile.
"Report by dawn," the clerk said, sliding another paper across the counter—a transfer chit. "Your housing will be reassigned to Sector Four. Don't be late."
Marvis took the chit and left.
The walk back to her quarter was a blur. Her mind churned, trying to find the trap in this sudden change. O-Negatives didn't get moved up. They got moved down. That was the law, the unspoken rule that governed every aspect of life in the city.
But here she was, clutching a transfer chit that would take her to a better sector, a better job, a room closer to Mira.
The Market always collects.
The Commander's voice echoed in her memory, and she shoved it down. She was being paranoid. This was luck—rare, inexplicable luck. Maybe someone had made a mistake. Maybe the universe had decided to give her one small kindness.
She reached her building and climbed the stairs, her legs burning with exhaustion. The door to her room was slightly ajar.
She froze.
The bolt was still thrown. She had locked it that morning. She always locked it.
Slowly, silently, she pushed the door open.
The room was empty. Her cot, Mira's cot, the small table with their single bowl and cup. Everything was in its place.
But on her pillow, there was a piece of paper.
She crossed the room in three strides and snatched it up. The paper was thick, expensive, the kind used by the high castes. On it, written in a precise, elegant hand, were four words:
You have been seen.
Her blood turned to ice.
She spun toward the door, but the corridor was empty. She pressed her back against the wall, her heart hammering, and listened. Nothing. Just the distant hum of the filtration systems and the occasional creak of the building settling.
She looked at the note again. The handwriting was unfamiliar, but the message was clear. Someone knew her. Someone had her room reassigned. Someone had been here, in her space, while she was working.
The Market always collects.
This time, she didn't shove the thought down. She let it rise, cold and certain, and with it came the face of the Commander—grey eyes, predator's smile, the casual cruelty of a man who saw people as resources to be managed.
She crumpled the note in her fist and shoved it into her pocket.
Then she began to pack.