Tuesday turned me into a volunteer in a neon vest.

  Patterson Park was all low winter sun and long shadows, the pond a dull mirror for bare trees. A Parks & Rec guy named Mr. Cannon handed me a grabber with a rubber claw, a bright blue bag, and a pair of work gloves that smelled like every shed I’d ever been in. “Stay with the group,” he said, ticking my name on a clipboard. “We’ll loop the paths, swings, and the hill by the pagoda. No needles—flag those for me. Anything else goes in the bag. Two hours. You got this.”

  I did. I could pick up cup lids and stray chip bags and candy wrappers for two hours. It wasn’t jail, and it wasn’t glamorous, but it was a lot easier than scraping a wall. A couple other kids in vests shuffled nearby—one with earbuds jammed in, one with hair dyed the color of a Slurpee. A jogger stretched against a tree. A woman with a stroller tucked a blanket around a squirming baby.

  We started along the path, the pagoda watching from the hilltop like a lighthouse. My grabber clicked pleasantly around a gum wrapper and dropped it into the bag with a papery sigh. A soda can rattled. A plastic fork surrendered after a stubborn moment wedged between bricks. The wind brought a whiff of charcoal from someone’s grill practice and the lake’s damp cold. For the first twenty minutes, my brain went blessedly blank—look, grab, drop, step. Repeat.

  Then the birds all left the trees at once.

  It was like someone had shaken the branches and poured sparrows. A dog that had been politely sniffing a bush froze, then growled low. My eyes went where my gut told them to: the street along the park, where a delivery van had just rolled to a stop at the sign.

  Something slid out from behind it.

  It was low to the ground and thick through the shoulders, a compact box of muscle the color of wet asphalt. Its head was wrong. Not a dog’s, not a cat’s—more like someone had bolted a shield to a skull, a plate that came down over its eyes and nose with two blunt, ridged horns curving forward like pried-up railroad spikes. Its back had a raised ridge of overlapping plates down the spine, and tucked between the shoulders was a hump that flexed when it moved, like a spring coiling. It put one splayed, clawed foot on the curb and breathed a visible white puff into the cold air.

  It saw the jogger.

  It lowered the shield and charged.

  I made a sound I’d never heard come out of me before and then realized no one else had reacted. The jogger was lucky. He started turning just before the impact and was only lightly clipped. His face did not do the thing a person’s face does when a battering ram with horns tries to reroute their knees. He looked confused and glared at the tree as the monster clomped past. The mom with the stroller steered away from the area—not like she was avoiding teeth and claws, but like she’d clocked “weird teenagers” cutting across the path and didn’t want them near her infant.

  Because they were there too. The girl first, a dark streak across the grass, her hair a black line at her back, the matte-green blade in her hand like a permanent extension of her arm. The boy half a breath behind, hoodie sleeves shoved up, the dull black sword coming up in a guard that would have looked stupid if it hadn’t been exactly where it needed to be.

  “Back!” he yelled—not to the thing, but to people, to bodies, to the crowd. “Get back!”

  A couple of heads turned. An older guy in a Ravens beanie frowned. “Put that away,” he called, half-scandalized, half-annoyed. “What is wrong with you?”

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  The thing turned in a wide arc and headed back toward the jogger, head down, breath puffing, that spring in its shoulders coiling.

  The girl cut its angle. She didn’t engage; she turned it. A slice of green near the shoulder made it flinch and pivot—annoyed, not injured. The boy stepped past it and swept his black blade low, not to cut but to draw a line. The creature’s shield swung toward him. He danced back. “Alley,” he said, short and sharp, and the girl nodded almost imperceptibly.

  They were herding it.

  To everyone else, it looked like two kids with props playing a game of chicken with empty air. A man pulling a cooler gave them a wide berth and muttered something about “cosplay freaks.” A teen with a skateboard held up his phone and filmed the boy’s footwork like it was a street performance.

  To me, it was a moving box of ruin that wanted to crack open whatever it hit.

  “Sinclair!” Mr. Cannon barked. I flinched. He was twenty yards away, eyes on me, not on the street. “Eyes up. With the group.”

  I took a step toward the street anyway, bag bumping my shin. The thing lunged. The girl feinted. The boy slid, brought the black blade up, changed the angle at the last second so the creature met pressure and not edge. “This way,” he said again, louder, and the thing followed the line of his weight into the mouth of an alley between a rowhouse and a pizza place.

  The girl flowed in after. The boy led, pivoting to keep the thing’s attention. The alley ate them, shadows swallowing detail. The ridge down the creature’s tail vanished last, plates rippling like a snake’s scales.

  “Sinclair.” Closer now. Mr. Cannon, not yelling but the voice that precedes yelling. “Stay with the team.”

  I stood on the edge of the path with my grabber hanging stupidly from my hand and watched the spot where they’d gone. I could still hear it faintly—the scrape of plate against brick, a low, angry huff that might have been breath, or my heart, or a truck a block away. A girl in a yellow puffer fell on the ice at the nearby rink and popped up grinning, still wearing the moment like a medal. The world didn’t tilt. It drew a line and dared me to cross it.

  I didn’t. I couldn’t. Mr. Cannon was ten feet away and closing. I turned my face back to the grass and stabbed the grabber at a plastic bag tangled in a shrub. The rubber claw closed around it with a snap that felt too loud. I dropped it into the blue bag and it made that light, empty sound plastic makes cause it doesn’t know it’s going to last forever.

  “What’s so interesting over there?” Mr. Cannon asked, following my earlier fixation. A delivery van rolled past. A woman tied her dog’s poop bag and looked for a trash can. The alley mouth was a rectangle of shadow and nothing else. “Stay on the path,” he said. “Plenty to do without getting hit by a car.”

  “Sorry,” I said. The word felt like chewing tinfoil. “Got distracted.”

  “Don’t,” he said, not unkind. He handed me a second bag. “You’re filling that one too.”

  I nodded and bent to my work. My fingers shook as I lined the claw up on a cigarette pack. Across the street, a guy in a Ravens sweatshirt showed his friend something on his phone and laughed. Behind me, a kid in a neon vest asked me if I’d found anything cool, like trash had tiers.

  The alley stayed a shadow.

  We looped the pond and the hill. I stole glances back every chance I could, but by the time we circled around, there was nothing to see. No suspicious noises, no cracked brick, no scrape marks on the curb.

  My bag got heavy. My shoulders ached. The two hours slid by, and the light did that thing it does where it all goes soft at once and the streetlights yawn themselves awake. When Mr. Cannon signed my timesheet with a flourish, my name looked steadier than my hands felt.

  On the way home, I walked past the mouth of the alley. It smelled like old pizza and cold. The only sign anything had happened was a dumpster at an awkward angle, and three small scuffs on the brick at knee height that could have been made by anything. A whiff of lemon cleaner and bleach made my skin prickle.

  I pulled out my phone, thumbed half a message, then tucked it away again without sending. I didn’t trust myself to send a coherent message. So I went home and put my vest on the back of a chair and washed my hands harder than necessary. And that night, when I closed my eyes, it wasn’t the wall or the girls or the rink that replayed. It was the moment that thing lowered its head and the girl cut its angle and the boy said “Alley,” and how everyone else kept moving like the world was only what they wanted to see.