Dea Rhodoreef envisioned many things she could do after school that day, but towing a sea cow wasn't one of them.

She swam backwards, kicking the water with her tail, and pulled hard at the makeshift leash. The animal didn't budge.

"Listen, cow," Dea burbled, poking the sirenian's smooth face. "You need to go home, understand? You can't keep following me."

He just looked at her with his little button eyes and drifted closer.

Dea let out a sigh, breath fizzing away in myriad bubbles. If the animal wasn't going home on his own, it was up to her to make sure he did. Her brain churned excuses she could tell the manager when she showed up late for the afternoon shift. Sighing again, she dug a hand into her backpack and pulled out a handful of seagrass—slender, green stalks against the turquoise of Calliathron's waters.

The button eyes that watched her shone like baubles, and a plump muzzle gave her a nudge.

"Manners, cow!" Dea held out the grass and watched it disappear in the blink of an eye. "You can't be that old, huh? You're small for a cow."

Indeed, the chonky mass before her was almost her size but nothing like an adult animal that could rival the bulk of a four-seater DSV. The muzzle gave her petite form another nudge, accompanied by a hopeful chirp.

"Well," she said, resisting the impulse to pinch his face, "you'd better come with me if you want more."

Dea gave the algal leash a firm tug, and this time her cow showed more enthusiasm about their excursion. She met the amused eyes of her neighbors, some of whom were swimming their otters. Her face heated up, but she bit her lip and pretended not to notice. Then she took off with a graceful thrust of her tail, towing her charge along.

In this plebeian corner of the city that Dea called home, the swimway wormed through mobile houses, stacked high against walls of coral. They were tiny smart domes in shells of eco concrete and titanium alloys—the state's response to affordable housing under a wave of modernization. Pinks and purples reflected off gleaming glass, as well as many darting fish, their scales shooting out sparks of light. As she passed by the coral outcrops, the biological noise hummed in her earpiece.

"Dea Rhodoreef! Where in the blazing geysers do you think you're going with a cow in tow?"

She winced and turned.

Her grandmother hovered out of a convenience store, a bioplastic tote bag trailing from the crook of her arm. Her starfish-printed dress puffed up when she joggled to a stop, hands on hips.

"Gramma." Dea offered a smile. "Hey!"

"Don't you hey me," her stern voice bubbled out. "Aren't you supposed to go to work?"

"But the cow..."

"If the cow found his way to you, then the cow can find his way back."

"But he hasn't, has he? This is the third day!"

Gramma made a series of clicks to express her exasperation.

"I'd like to keep him if he wants to stay," Dea mumbled.

"Sometimes I wonder if your head is stuck in a bubble. You give me more headaches than those darned humans—always in the news with their diabolical ways." Gramma shook her head. "Who's going to look after him?"

"I am! Stop treating me like a kid, Gramma. I'm eighteen this week for blubbering out loud!"

"Exactly. There's responsibility you need to shoulder." Her face shadowed under the deepening wrinkles, and she waved a hand at the languid animal. "And that doesn't mean...fostering a wild cow!"

"Why do you keep talking about responsibility all of a sudden?" Dea crossed her arms, ignoring the amused look a merman gave them while exiting the store. "Plus, I'm doing my best, Gramma. The Youth Council was impressed with my presentation at school today. It was on how we can solve our current issues—"

"By fraternizing with humans, no doubt." Gramma snorted. "What codswallop! The day they discover us will be the end of everything! You're going to get into hot water one of these days, young lady."

Dea rolled her eyes.

The merwoman went on, her voice lowering, "I don't know what's going to become of us when you youngsters get into power. You stay away from that Council. And stop feeding that animal—"

"Why can't you let me do what I want for a change?"

"You can't keep a cow in my house!"

"Fine."

Dea gave her no time to react as she yanked on the leash and fled, her peduncle muscle powering through the water. The sea cow caught up with her—as if he understood the whole exchange. Currents swept out behind them when they picked up speed.

Gramma recovered enough to yell, "You get back here this instant, young lady!"

Clicks aimed at Dea's back followed her well after Gramma's rotund figure disappeared from view. She ignored them. Holy sea cow! At least she's not tech savvy or my ogi would be flooded with calls and pings.

Eventually, she neared the tunnels leading out of the city.

The reef displayed splotches of ghostly white, which became more pronounced the further she went. It was a slow pestilence that stoked the undercurrent of disquiet with each passing year. Autonomous vehicles and delivery pods jetted by in a steady stream, some carrying cargo from outlying factories and mining stations. The whir of mer-activity overlapped the natural ambience, though it was even louder than usual. Dea soon saw why.

Protesters swam together, schooling like herring—fifty, hundred or even a thousand. They chanted and brandished placards. She shook her head as she read "stop the human virus", "bleach your ass, not our corals" and "yeet 'em to the south pole." There were also insults aimed at the "mudskippers", a rude term for pro-human youth.

Dea observed the cow's panicky reaction and paused to give him a reassuring pat. "Nothing to be afraid of—I'm right here. And I'm going to take you all the way home, okay? Your family must be looking for you."

As she bypassed the crowd, the noise peaked and then dipped. A moment later, her smart-ogi came alive with insistent vibrations in her waist pouch.

She extracted it and unfurled the screen in one fluid motion. "Hey, Hima!"

"Hey, are you done now?" Hima's face loomed on the screen, pearl hair waving as listless as a sea whip. "Dalla's asking questions already!"

Dea flashed a hesitant smile and tilted the ogi to show off her animal companion.

Her friend facepalmed. "I'll figure something out till you get here."

"Thanks!" Dea couldn't help admiring the iridescent ripple of Hima's hair while her own face stared from the corner with pastel pink waves. "I owe you."

"By the way, there's a cyclone alert."

"Huh? Really? That's too soon since the last one."

"Mhmm, scarily frequent." Hima gave her a look. "You'd have known if you checked the news once in a while."

"I would—if it wasn't spewing out propaganda." Dea emitted a dismissive click. "I won't venture out that far. I'll be back soon."

"Good."

After stopping at an air kiosk to replenish their oxygen, Dea swam out of the coral atoll that contained the city of Calliathron. Her path took her in the direction of the nearest seagrass meadows, past warehouses and garages. As she crossed the invisible divide between civilization and the wild, sparse dwellings gave way to flourishing vegetation.

The sea cow uttered a string of barks.

She nodded. "Yep, home."

They floated over the carpet of greenery. Wild grass swayed in the current while fish raced away at their approach. There was no sign of sea cows. Dea fired out clicks to echolocate, but even the ogi's sonar didn't pick up any large animals in the vicinity.

"Where's your family, cow?" Dea wondered out loud. "How did you get separated from them?"

He was too busy eyeing the seagrass. She giggled and untied the leash, her hands stroking the blue-grey skin. He immediately started grazing. As she stowed away the leash in her backpack, she noticed the dappling patterns of sunlight, which dimmed as she watched. It made her black halter top even blacker, the lace patterns hardly visible.

Dea propelled herself up and broke the surface. As she gulped in lungfuls of air, her skin tingled with static. High above, dense cumulonimbus clouds gathered with surprising speed and painted the skies grey. Her brow creased into a frown. The cow probably has little experience with cyclones.

She dived back down and almost reached him when a spark of light entered her peripheral vision. She turned to see an amorphous shape drifting weightlessly away.

It was a bag made of human plastic.

Her heart skipped a beat. Unease pooled in her gut, but excitement got the better of her. She approached the human invention. It glistened white while the hand of nature dulled and darkened the seascape. She had heard many a tale of human plastic—how it was as delicate as kelp bioplastic, but indestructible, even with the passing of centuries. As she stared at it now, it was hard to believe it could wreak so much havoc. The water suddenly felt cold.

Humans know no better—all the more reason to make contact. She set her jaw and almost dropped her ogi in her hurry to snap a photo. Then she called her friend.

"Dea," Hima said, urgency saturating her tone, "get back—"

"Do you see it?" she interrupted in a hushed burble.

"Is that..."

"Mhmm. I wish it was a human." Dea grinned. "Number one off my bucket list."

"You're so insane!" The other girl let out a nervous laugh.

"How did this get here though?" Dea circled around the object and flapped her free hand in an effort to halt its motion. "Wow, d-do you think humans have come here?"

"No way, that's ridiculo—hey, don't touch it!"

"Why not?"

"I dunno..."

Dea rolled her eyes and giggled. "I'll see you later, okay?"

After ending the call, she put away the ogi and touched the translucent bag. It slithered over her tan skin. Before she could hold it, a strong current sent her tumbling forward. Her tail flukes bumped into something on the seafloor.

It was a dead sea turtle, a tangled mess of human plastic trailing from its mouth.

Dea flinched, air bubbles escaping from her mouth. She tore her eyes away from the sight. That was when she realized the sea cow was gone.

She spun around and saw the chubby animal drifting further out over the seagrass. Worry clouded her mind, and she chased after him. Out of all the merpeople in Calliathron, the cow had followed her, so it was her responsibility to get him home safely. She could never forgive herself if something happened to him.

As she gained speed amid the increasing turbulence of the water, her heart guzzled her oxygen stores. Part of her brain urged her to turn back. Cyclones had devastating power—she had witnessed the damage they dealt to the coral reef. Childhood memories surged on cue—a night of chaos and destruction that made her insides roil. These disasters would only grow worse unless they acted, but the state would rather hide in a nook in the ocean and blame the land-dwellers, who inhabited only a fraction of the planet's habitable space. Her fists clenched. She had to crawl up to a position of power and change policy.

She rushed to the surface for a breath of air but barely sucked it in when a colossal wave rolled over her and plunged her back under. The current pushed her to the bottom and blew her away like a palm frond. Seagrass waved in a frenzied dance, slapping against her flailing arms. She opened her mouth to shriek, but water sloshed in, its salty tang hard on her tongue.

Then she hit the rock—an outcrop that sent her bouncing off on impact.

Pain erupted on her head. Her vision blurred and ears rang.

Dea lost sense of space and time as the cyclone pulled her into its vicious hold. Her throbbing head barely registered the fact that she was swept away into the open ocean.

An eternity elapsed—or so it seemed.

By the time she regained a modicum of control over her tumbling form, she found herself jounced about on the surface under a barrage of heavy rain. Howling wind whipped her face. Spluttering and blinking, she bore witness to the ocean's dark fury.

Bolts of lightning flashed on her retina, imprinting the sight of monstrous waves that towered impossibly high. Thunder warred with the boom of water and battered her eardrums. She reached up a shaking hand and jabbed at her earpiece to dull the relentless assault. It did little to ease the pain in her head, which thrummed in sync with her thudding heart.

It took a few more seconds for her to realize that she was well away from the coral atoll she had known all her life.

The very idea was unthinkable. She didn't even know anyone who had ventured out, except on authorized routes to factory outposts. Her chest tightened, and she drew in one shuddering breath after another. Calm down. Calm down.

That was when she spied it.

She coughed out water and gave her head a shake. She put it down to a hallucination due to head trauma. Lightning illuminated the object yet again.

It was a human ship.

Her eyes goggled, in danger of falling out of their sockets. Even in her dazed state, her mind went into overdrive to wrap around the fact that she was seeing a real human ship. Fear bubbled within, born of uncertainty, while the forbidden thrill of a human encounter kept her gaze glued to it.

As she bobbed in and out of the water under the leaden storm clouds, she scanned its contours, slick with spray. Despite its size, it rocked precariously on the roiling seas as if it were nothing but a toy. Waves crashed over the bow, threatening to smother it with spume. Her gaze panned to the deck, where she detected a hint of movement.

A long minute passed. The right choice was to flee. That was what her city-state expected of her. That was what Gramma expected of her—she could almost hear the old woman screeching for her to get back. Her fists balled.

Dea swam towards the vessel.

Even at her sluggish pace, constantly thrown off course, she reached the ship sooner than she anticipated. Her jaw dropped open as she took in the lurching mass at close quarters, gleaming under dramatic bursts of lightning. Tremors shot down her entire body, nerves alight, as if electricity seeped into her very bones. Dea steadied her breathing and strained to catch sight of a human.

Her wish was granted when a gigantic wave almost tipped the boat sideways, and a human flew overboard.

It was a real human, tossed by the elements—too puny to live up to the notoriety.

What followed seemed to happen in slow-motion—her silent scream, the flash of brown hair and her eyes latching onto the body that appeared suspended in midair for a nanosecond. Then the human fell into the churning darkness below.