When the wagon shuddered to a halt, I startled out of my reverie. I hadn’t dreamed that I could remember, but I felt as though I were waking from a deep slumber all over again. The wagon had started to move, and I had watched as we rolled past cobblestone streets lined with buildings, and then the town gate, and then barren fields dotted with houses. After that, I remembered thinking that that would be the last time I ever passed through that gate a free man, but then the rhythm of the road and the lack of rest had hypnotized me.
The latch on the back door rattled, followed by the creak of hinges as it swung wide, letting a fresh stream of blue light and chill air. I shook off the last of my trance as Milos poked his head inside, catching my gaze. He gestured to the other two, then beckoned me to follow. I tilted my head to the side and opened my muzzle, but he quickly lay a finger across his lips, then shook his head. He jabbed a clawless finger firmly in the direction the lynx and other wolf sleeping against each other, tucked into the opposite corner, and understanding dawned.
The lynx’s eyes opened as I nudged him with my hind, and he nodded his response. He bumped the other wolf with his shoulder, then again when she tried to turn away. She lifted her head and turn from him to me, then drew in a deep breath and nodded herself. Together, we carefully crawled out of the back of the wagon into Milos’ waiting paws as he helped us stand. The ground was hard-packed dirt that leeched heat out of my pads, in front of a low, broad building. At intervals around it, a half-dozen wagons sat parked, probably other slavers or possibly buyers. Some of the dray teams had people attending to them; others had slaves tending their needs, clearly distinct from their lack of clothes and the glitter of metal bands at neck and wrist.
Milos clapped twice, pulling my attention away from the area and back to him. He put his arms to the side, indicating the ready pose, and I complied, bowing my head, my ears back against my skull. The slaver’s pet started brushing the straw out of my pelt, delicately picking fibres out of my fur. He was both thorough and embarrassingly casual, brushing my sheath with his pads and combing over my tail with his fingertips. He even lifted my legs, holding the bar between my manacles to steady me, in order to brush the pads of my hinds.
As he was finishing up with the lynx, the slaver returned, holding aloft a sheaf of parchments in one paw and a leather sack in another. “Good, he’s taking care of you,” she said lightly. “I’ve gotten you all good spots in the main hall; it cost me a bit, but it’s been worth it on every sale. Milos?” The wolf dropped to his knees, head bowed. “Rise, finish your work, and then attend to the team. I’ll take them from here.” Her personal slave’s head bobbed, and then he rose, resuming his inspection of the lynx’s fur while the slaver turned her attention to me. “Head up, hold this.” She handed me the sack, which I took while she shuffled the pages, looking between them. “Yes, here we are.” She took the bag from my fingers, then rummaged through it before looking back into my eyes. Her fingers went to my throat, and then something heavy and metallic clacked into place, adding a bit of weight to my neck. “Lot number eleven-fifty.” She stepped past me to the lynx, affixing a metal tag to his collar, then finally to the female wolf.
As Milos shifted his attentions to the last of the group and began grooming her, the slaver began her own inspection, her tailtip flicking lazily behind her as she pored over my fur. She looked into my ears, then clucked her tongue disappointedly at the patch of black on my shoulder again. “Pity,” she murmured, grinning. “No matter. You’ll still fetch quite a price. All of you will.” She nodded to herself, then stepped behind me and stroked my tail, sending a shiver up my spine.
Satisfied with my appearance, she did similar with the other two, then stepped in front of me and clapped twice. “Milos, you have your instructions. The rest of you, follow.” She then turned and led us into the building, through a gate large enough to fit two wagons beside each other. A guard at the entry, his breastplate bearing the interlocked rings of the Slavers’ Guild, checked our tags and her pages, then nodded and motioned at her to proceed. Inside, the air was filled with golden witchlight and the scents of fresh straw, sweat, and fear. The interior looked like a converted stable, with rows of stalls in one direction, and banks of tables in the other. Slavers led their wares around, some in shackles, some on leashes, some simply following behind. Others, much better dressed, stood in groups and chatted amongst themselves, their servants scurrying about to attend to their needs.
The raccoon currently holding my life in her claws checked the sheets of parchment in front of her, then pointed. “End of the row, seven to nine. Follow.” She led us past a few empty stalls, and one in which a single tan-furred vole knelt, her head down, her knees apart. Whoever had brought her to sell hadn’t taken the manacles off of her wrists, or the gag out of her muzzle. A cuff around her tail held it to the back of her collar. Hanging from the front of her stall, a large sign clearly stated, As-is, all sales final.
At that, the slaver laughed. “Oh, perfect.” She gestured to the occupant of the other stall, who lifted her head, sensing she was being discussed. “That has to be Betorik’s work.” At the name, the vole flinched, making the raccoon chuckle. “I suspected as much. He prefers a good deal of fight in his pets, so most of his offerings have almost no training. I would accuse him of raiding, but the Guild would have more than his membership if he did.” She looked down at the slave and smiled. “At any rate, with that as your comparison, you should all do very well. In fact, I doubt we could have asked for a better position. Follow.” She walked down to the end of the row and started unlocking doors.
The vole pleaded with me with her eyes as I walked past her. With breath caught in my throat, I turned my gaze away and walked into my own stall. Sized to hold a dray, the space seemed oddly large compared to the cage from the Slavers’ Guild and the covered wagon. The floor was lined, and a bulging waterskin hung from the wall, capped with a rubber stopper. While I stepped into the confines and knelt, the slaver tacked one of the sheets of parchment to the wall separating me from the people who would pass.
When she closed the gate, the latch dropped into place automatically, effectively trapping me. I could hop over the wall perhaps, but not without falling on my face, and even were I to do so, where would I go? The slaver leaned on the barrier, holding the key for me to see. “A few final rules for you,” she said, her eyes focused on me. “If someone asks you a question, you will answer it. If someone asks you to perform within the stall, you will do it. If you cannot, you will apologize and then explain why. If someone tries to enter your stall, or to make you leave your stall, without someone from the Guild in attendance, you will scream. Do you understand?”
I held very still for a moment, considering, then nodded.
“Well, that would be everything, then,” the raccoon said as she stood, dusting her paws against each other. “Do your best to fetch a high price. They frown on sellers being on the floor once the bidding has begun, so unless no-one buys you, this is it.” She smiled at that. “I find it unlikely that will happen. You’ll make your new owner very happy.”
Suddenly, I raised my head. “Master?”
The raccoon had started to walk away when I spoke; she paused and, though she didn’t look at me, I could imagine her frown in response. “Yes?”
I opened my muzzle, but suddenly every word I had left me. I looked down, blinking. “I… I don’t even know your name,” I finally said.
She smiled, folding her arms across her chest. “No,” she replied. “Nor yours. For now, however, you’re Lot 1150. Remember that, if you hear it. Good bye.” Then she disappeared past the wooden wall, walking to the next stall in the line.

This section leaves me quite curious as to the how of people getting sold into slavery. I mean, if actual raiding (and I take that to mean raiding villages / abducting people off the street) is prohibited, then by what means do people find themselves enslaved?
Without wanting to go too heavily into the history of the world as it existed prior to the story and isn’t immediately relevant, the origins of the institution lie in prison sentences, indentured servitude, and class repression. Slavery was a punishment for those who rebelled against the social order, and as they became more “enlightened,” a way for people to resolve debts they couldn’t otherwise pay. Manumission—releasing slaves—isn’t unknown, though it isn’t common either.