The air east of town was different.
The sweetness had faded, replaced by a stuffy sensation, like burying your face in a wet cloth. The color of the mucous membrane had changed too, from pale green to gray-green. Its surface was no longer smooth; in places, it had wrinkled like an old person's skin. Every so often, one or two wrinkles would slowly contract, squeezing out a little gray liquid before quickly drawing it back in.
Winston slid along ahead of him, moving more slowly than before. The outline of his body hadn't changed, and his top hat still sat firmly on his head, but the light of his core had dimmed by half a shade, shifting from orange to the darker end of amber. When he passed over a particularly gray stretch of mucous membrane, the edge of his body shrank slightly, like someone unconsciously hunching their shoulders while walking through a cold draft.
The cat merchant noticed. He didn't ask.
"It's just ahead." Winston stopped and turned to look at the cat merchant.
Ahead stood a round building larger than the others. Its surface flowed very slowly, and it was a deep indigo, like a drop of night that had solidified. A slime stood at the entrance, a ring wider than Winston, her body a steady dark green and her core glowing with a soft white light. She wasn't maintaining a humanoid form. Instead, she had taken on a shape somewhere between a cylinder and a hemisphere, resembling a small tower.
"Mom," Winston said, his voice growing softer. "This is the apothecary. He came from the north."
The mayor turned around. She had no eyes—or at least none that were obvious—but the cat merchant could feel her looking at him. It was a strange sensation, like being watched by an entire lake.
"So you're the cat." Her voice was different from Winston's. It had no ripples, only a steady weight, like a stone sunk to the bottom of a lake. "Gran wrote me a letter."
The cat merchant's ears twitched. "Gran's letter traveled faster than I did."
"A dwarf carrier pigeon is faster than your wagon," the mayor said. There was no humor in her tone, but neither was there any hostility. "He said you could treat difficult illnesses. He didn't say you were wanted by the law."
Winston's hat tilted slightly.
"I'm an apothecary too," the cat merchant said without changing his tone.
The mayor was silent for a while. Her core flashed twice, as if she were thinking.
"Come in."
It was darker inside than out. The walls themselves were the light source—the indigo walls glowed slowly, like moonlight steeped in water. The floor was covered by a thick layer of gel. His paws made no sound as they sank about half a finger's width into it. Each time he lifted a paw, the gel gave a soft little tug before silently closing up again. A faint salty smell hung in the air. It wasn't the salt of the sea, but something heavier and older, like the trace left on skin after tears dried.
Three slimes lay on gel mats.
No—not lay. They were sprawled out.
Their bodies had lost their normal tension, like water balloons that had been punctured, their edges slowly spreading outward. Their colors were wrong too. One slime that should have been pale blue was covered in large gray-white blotches, as if it had been bleached. Another had fine cracks across its surface, with pale yellow liquid seeping from them. The third was in the worst condition. Its body had become almost completely transparent, and the light of its core was as faint as a candlewick about to burn out.
The cat merchant crouched beside the first one.
He didn't touch it. He smelled it first. When he brought his nose close to the gray-white blotches and inhaled, his ears snapped back.
Acid. But not the acid of slime bodily fluids.
This acid had a sharper, narrower smell, like a needle stabbing straight into the depths of his nasal passage. His nose wrinkled, and he leaned in for a second sniff, slower this time, letting the scent linger in his nose for several seconds. Beneath the acidity, there was something else, faint enough to be almost completely masked—a warm, fatty scent, like the trace left behind by some living creature.
He pulled a thin glass rod from his leather satchel and lightly touched the edge of a blotch. A layer of white fog immediately formed on the tip.
"Strong acid," he said, his rhythm changing to the quick, precise cadence he'd used in the mine. "But not an inorganic acid. It's organic, with a protein structure." He lifted the glass rod to his nose and smelled it again. "And there's residual biological matter. This isn't a chemical reagent. It's secreted by some kind of organism."
The mayor's core shifted slightly, and its white light swept across the cat merchant's face. She said nothing, but a ring of extremely fine ripples appeared on the surface of her body, spreading outward from her core like a pebble dropped into water.
He stood and moved to the second slime. The cracks were unevenly distributed, concentrated on the right side of its body, as though something had been splashed on it from one direction. He drew the glass rod along the path of the cracks, from the edge toward the center. The closer they came to the center, the deeper the cracks grew. At their deepest point, they had split through the surface, and he could see bodily fluid slowly seeping out from underneath. It was yellowish, with a hint of rotten sweetness.
"The attack came from the upper right." He spoke to himself, then crouched to examine the angle of the cracks. "The splash height was probably here—" He gestured at roughly chest level. "Higher than the slime's body, splashed from above."
Winston watched from the side, the core beneath his hat brightening and dimming as if he were holding something back.
The cat merchant stood and went to the third one.
The third slime's condition was different. There were no blotches or cracks. Its entire body was simply turning transparent. The cat merchant crouched beside it and studied it for a long time. The slime's outline was still there, but its boundary had blurred, like a piece of ice placed in warm water, disappearing little by little. The light of its core wasn't dimming steadily. It was trembling—a very faint, irregular tremor, like a person shivering with a fever.
He extended his hand, palm down, and held it above the nearly invisible body.
He closed his eyes.
A very faint heat came through his palm. It wasn't normal body heat, but an abnormal warmth, like an inflamed wound burning outward from within. His fingers spread slightly as he sensed the distribution of the heat. It was uneven, concentrated around the core, as though something were spreading outward from it.
After a while, he opened his eyes, and his expression changed.
"This one wasn't splashed." He stood and turned toward the mayor. "The first two were external attacks. Acid was splashed onto them from outside. But the third one started from within—his bodily fluids themselves are being altered."
The mayor's core flashed. "What does that mean?"
"Something got inside his body and is slowly turning his bodily fluids into strong acid. He wasn't burned. He's being dissolved by his own body."
Winston's body shook violently, and his hat nearly fell off.
"How could that…"
The cat merchant didn't answer. He crouched beside the third slime again and took a small copper box from his leather satchel—not the one containing the stone-eating bug gastric fluid, but another, smaller one, with a ring of runes engraved on its lid. He opened it. Inside was a thin layer of fine gray powder.
He dabbed a little powder onto his fingertip and lightly sprinkled it over the transparent body's surface.
Several grains lit up the instant they landed.
Not all of them—only three or four. They emitted an extremely brief red glow, then went dark. The points where the glow appeared weren't on the surface but deep inside the body, like embers sunk beneath the water.
The cat merchant stared at the spots that had lit up, his eyes narrowing.
"This powder detects foreign biological residue," he told the mayor. "The spots that lit up indicate biological components that don't belong to him. And they're not on the surface. They're inside, near the core."
He paused, lowering his voice by half a note. "This didn't enter from outside. It was fed to him, or mixed into something he would eat."
The mayor's body surface suddenly solidified. All movement stopped, and even the light of her core froze for an instant. In that moment, she didn't look like a small tower. She looked like a stone.
Then she moved. The white light of her core brightened by a shade. Her voice remained steady, but it was too forcibly steady.
"Are you sure?"
"I'm sure." The cat merchant put away the copper box and stood.
He stood up and put away the copper box.
"Three victims, two methods of injury. The first two were direct attacks; the third was infiltration. But the thing that caused the damage is the same—a strong acid secreted by some kind of organism."
He paused and looked at the mayor.
"Have you seen any unfamiliar outsiders in town lately?"
The mayor was silent. Her core slowly made one full turn, its white light sweeping across the entire room.
"Travelers passing by the edge of the marsh show up from time to time," she said. "But few come into town. There's not much here worth stealing."
"This isn't theft." The cat merchant wiped the glass rod clean and put it back in his leather satchel. "Someone is deliberately harming your residents. And it's happened more than once, in more than one way."
He went to the door and glanced back at the three slimes sprawled on the gel mats. The most serious case had dimmed another shade, and its trembling had grown faster, like a candle flame in the wind.
"I can treat the first two. The abrasive compound made from stone-eating bug shell residue can neutralize the remaining acid. Combined with your own bodily-fluid regeneration, they should stabilize in about two days."
"What about the third?" Winston asked.
The cat merchant didn't answer right away. He stood in the doorway as the setting sun shone in from the marsh, stretching his shadow long. It fell across the gel floor, half swallowed by it, like it was sinking into water.
"For the third, I need to find out what that thing is first," he said. "Only then can I get it out of his body."
He went outside and stood on the mucous membrane for a while. The marsh was quiet in the evening. In the distance, several small groups of slimes slowly rolled across the mucous membrane, their cores glowing in various colors like stars scattered across the ground. But beside those stars, several stretches of mucous membrane were gray—jarringly gray, like bruises growing on healthy skin.
Lolo had followed him at some point. Three heads poked out from behind a marsh banyan, six eyes watching him. The middle head tilted, ears pricked forward, as if asking what was wrong.
He walked over and crouched beside Lolo. The head on her left leaned over and sniffed his fingers. When it caught the scent of powder lingering on the copper box, its nose wrinkled, and it let out a tiny sneeze.
He smiled briefly, then pulled his little notebook from his leather satchel and turned to a fresh page.
He wrote: "Organic strong acid, secreted by an organism. Two attack patterns—external splashing and internal infiltration. Same source. Not a native marsh organism."
He paused, the tip of his pen hovering over the paper.
Then he wrote: "Third victim: acid generated internally. Not splashed—fed. The culprit is not outside."
He read those last four words once more, then added a line beneath them in even smaller handwriting: "There's something very faint in the acid's smell. Like the scent of burning feathers."
He closed the notebook and looked up at the sky. The marsh sky was vast, completely different from the narrow slit above Rockrun. The clouds hung low, their edges stained orange-red by the setting sun.
The head on Lolo's far right rubbed against his hand.
"Someone's bullying the people here." He stroked her head, his voice very soft. "And whoever it is knows how to hurt slimes."
He stood and brushed the mud from his knees.
Beneath his cloak, a third tail emerged again. This time, he didn't tuck it back in.