"Who was it?" her mother asked, still busy with dinner.

"I'm not sure," Roxi answered, confused. "Someone doing a late Halloween prank, I guess?"

She made her way back to the kitchen, where she had been working on her homework at the bar.

Her mother was chopping vegetables, by the sink. Roxi stretched over the cool countertop, not eager to return to her essay. It was hot for November, warm enough for shorts, and she was on the verge of melting.

"What kind of prank? Like, a TikTok?" her mother guessed.

"Yeah maybe," Roxi shrugged, her arm sticking to the counter she was laying half across. "Nothing I recognize. Something about chemicals."

She yawned, fighting the urge to close her laptop. It wasn't like she had been making any progress on her essay, but she had promised her parents she'd at least try. Almost being held back a grade once was humiliating enough; having to have that talk with your parents was gut-wrenching.

Her mother stopped chopping, and turned to look at Roxi over her shoulder.

"Something chemical?" she pressed. "Did they give you anything?"

Roxi shook her head, suddenly very sleepy. It was so warm, and she was so tired. She coughed, and her vision swam.

"Roxi? Roxi, honey?" she heard her mother, but she was suddenly calling from somewhere far away. "Roxi!?"

Roxi fell, gasping, into oblivion.

There were noises from outside, she realized. People were yelling.

She coughed, and it was like being kicked in the chest. She coughed again, dizzy, sick. She tasted something nasty, and her head hurt. When she moved, her skin felt like it was on fire.

Roxi fought for breath, gasping, choking. She wheezed wetly, fighting to get enough air. Fighting unconsciousness, she forced herself up. It was like waxing her whole body at once; her skin felt like it was tearing. But she couldn't breathe enough to scream.

She had somehow been moved to the couch. Disoriented, Roxi stumbled around to find the door. Yanking it open, she stood gasping in the doorway, leaning hard against the wall.

Outside was chaos. People ran, screaming, choking, coughing, hacking. Men ran, carrying their children on their shoulders. People were wearing masks, cloths, rolled up shirts over their mouths and noses. Children, closer to ground level, were gaping like fish, struggling more than the adults. Roxi panted weakly, watching a toddler being dragged by the hand by his mother, saw when he went limp. His mother reached down to scoop him up but fell beside him, coughing and gasping.

So many people were moving, but she didn't immediately understand where, or why. Cars were stuck, traffic standing still, and people were abandoning their cars, climbing on top of them. The ones moving, mostly moved in one direction. Uphill, she realized.

She coughed again, wetly, and spit out blood. Blearily, having trouble concentrating, she turned and unsteadily made her way back to the kitchen. She wanted to join them, wanted someone to show her where she could go to breathe. But there was something important she was forgetting. She just had to remember what it was.

She broke into coughing again, spitting blood and doubled over with the pain of it, before she found it: her mother, sprawled out on the floor in the living room. Roxi tried to bend down to help her, but she tasted a lungful of the horrible air, and realized why everyone was moving uphill. She couldn't breathe at all, nearer to the ground.

With shaking hands, she exhaled as she brushed the hair away from her mother's face. Her mother's white face, her blue lips, her black tongue. Bloodshot eyes stared unseeing. Roxi's mom had spent too long helping her, lifting her, carrying her to the couch. Her mother had unwittingly killed herself, saving Roxi.

She lurched, dizzy, and almost fell. Her mom was... no. She couldn't... mustn't think about it. She thought about her dad, her sister instead.

"Phone," she slurred, staggering. "Daddy."

A light flashed nearby. Her oxygen deprived brain thought it recognized it. Coughing, gasping, she climbed onto the coffee table, grabbed the ceiling fan for support.

"Aleshsa," she tried, then wiped the blood from her mouth. "Alexa. Call dad."

She gagged, retching, as the light flashed obediently.

"Calling: Dad."

It rang. Rang again. Her fingers hurt, holding the fan blades, but she could almost get a breath that didn't splash inside her. The call went to voicemail.

Al-" she started, then coughed hard, spraying blood on the wall. She blurted it, afraid she would lose the ability to talk. "Alexa call dad."

Ringing. Ringing. Voicemail.

"Alexa, ca-" she said, voice breaking as she fought not to cry.

She was dizzy. She was off balance. Her fingers slipped, and she fell. Flailing, she tumbled. Into the bad air, into the gas.

She landed hard, what little breath she had knocked from her. She tried not to gasp, tried not to, tried so hard to fight her way back up to her feet before she took that breath... but her body betrayed her. She collapsed, helpless, and she breathed.

Her lungs and her eyes opened at the same time. It burned, it stank, it hurt. It broke her heart. Facing her, almost kissing her, her mother's corpse lay beside her.

Unable even to cough anymore, her lungs a twisted knot pouring blood into her chest, Roxi reached out and touched her mother's hair. Her final breath was a gurgling wrench of pain, boiling messily inside of her. Roxi's vision darkened, and in that final moment, she thought she saw her mother's body smile, thought she felt her mother's cold arms wrap around her and pull her close.

The last good thing in the world went out of her, there in the gas, but at least she wouldn't be alone.

• Inspired by true events.