Before you move into a new place, you're supposed to leave the windows open for a whole night, to let the old air drain out clean.
I rented a room. The landlord said the previous tenant had moved out two months ago and the place had been sitting empty, so I opened the windows to air it out.
The next day I went back. Every window was shut. The latches were locked tight from the inside.
The landlord said she'd never been there. After I moved in, I heard the window latches clicking every night.
Click. Click.
---
Cheng Shi stood at the apartment door, his rental app still pushing "bargain steal" notifications. He swiped the pop-up away with his thumb, slid the key into the lock, turned it twice. The door opened.
A smell rushed out—the kind that comes from a place left too long alone, where the air has worn itself thin against itself. Not rotten. Just thick, catching in the throat.
Sixth floor, no elevator. An old complex. The stairwell was papered with ads for drain-clearing and locksmiths, the white paint curling up in flakes like dried fish scales. Cheng Shi climbed all six flights. His back was damp.
He'd quit his last job yesterday. Money was tight. This place was cheap enough to feel wrong, and the agent said it was because the landlord was desperate—the previous tenant had moved out two months ago, and the place had sat empty ever since. No one had even come to look at it.
"Go in and see for yourself—good layout, south-facing. Only catch is the floor, no elevator," the agent had said on the phone. "The landlord says if you rent it, one month deposit, three months upfront, but I'll knock five hundred off the first month. Call it stair-climbing compensation."
Sounded like a deal. Cheng Shi had been sharing a place before, and his roommate brought people home at three in the morning, going at it on the living room sofa without even taking off their shoes. He'd put up with it for six months. Then he couldn't anymore.
The living room was small but genuinely south-facing. Four o'clock sunlight came in at an angle, picking out the dust on the floor. Countless tiny particles hung in the air like snow that had stopped falling.
Two bedrooms, one south, one north. The south one was bigger, with a balcony. The north one was tiny—room for a bed and a wardrobe, that's it. Kitchen and bathroom were clean. Someone had at least been thorough.
Cheng Shi walked a loop through the place, then pushed open the south bedroom window. The aluminum frame was stiff; he had to put weight into it. A few yellowed leaves hung on the security bars outside. The wind came, and the leaves tapped against the iron. Tap. Tap. Tap.
He remembered the thing you're supposed to do before moving in.
His old roommate had taught him that. A delivery driver in his thirties, the kind of guy who believed in this stuff. He'd said that if a place has been empty for a while, you've got to open every window a day before you move in, let the wind blow straight through, clear the old air out. Otherwise you'll have nightmares. Your luck turns bad.
"What's old air?" Cheng Shi had asked.
"It's what the last person who lived there left behind," his roommate had said. "Emotions. Illness. All the junk thoughts. You stay in a room long enough and that stuff soaks into the walls, the floor, the furniture. When no one's living there, it just sits in there and ferments. One night with the windows open and it can finally blow away."
Cheng Shi had figured it was superstition, but he hadn't argued. Later he looked it up himself. Some people said it was really just a folk way of clearing out formaldehyde and mold—a different name for the same thing. Made a kind of sense. And opening a window cost nothing.
He walked to the north bedroom and opened that window. It faced north, onto the back of another building, close enough that he could almost touch the opposite wall. Old-style sliding window, the screen torn in a few places. He gave it a pull. It slid smooth—easier than the south bedroom.
Both bedroom windows all the way open. Living room window open. Kitchen and bathroom windows propped. Wind poured in from the south, cut through the living room, and slipped out the north window with a thin moan.
Cheng Shi stood in the middle of the living room. The throat-clogging smell had thinned. The air was moving.
He shut the front door and threw the deadbolt with his key. Tomorrow he'd just have the movers haul everything over. He only had a few boxes and a fold-out bed. Nothing big. Still, it took him half a day to line up a van.
That night he slept on a mat at his friend Zhou Ming's place. Zhou Ming asked how the apartment was. He said fine—cheap, south-facing. Zhou Ming said cheap means something's wrong, be careful. Cheng Shi said he'd looked around, nothing seemed off, it had just been empty a while, and he'd left the windows open to air it out today. Zhou Ming said, so you can move in tomorrow? Cheng Shi said yeah.
"Moving in alone?"
"Not much stuff. Two trips, done."
Cheng Shi lay on the mat. Zhou Ming's cat padded across his stomach. He turned over and fell asleep.
---
Next morning he woke early. Zhou Ming was still asleep. He washed up quietly, took the subway to the new apartment. Third time climbing those six floors. He was getting used to it. His legs didn't ache like yesterday.
He froze with the key in the lock.
The deadbolt wasn't thrown.
He'd definitely thrown it yesterday. He remembered clearly—the lock was stiff, and while turning it he'd thought it could use some oil.
The door opened. The living room window was shut.
Cheng Shi stood in the doorway without moving. He looked at the window first. The sliding panes were closed, latched from the inside. The aluminum frame sat flush in its track. Not a breath of air could get through.
The south bedroom door was open. He walked over. South bedroom window shut, latch on. North bedroom—shut, latch on. Kitchen. Bathroom. Every window he'd opened yesterday. All closed. All latched dead tight from the inside.
Cheng Shi stood at the north bedroom door, staring at the little latch. Iron, a little rusted, seated in its slot on the frame. He reached out and touched it. Cold. The window was shut tight. He pushed outward. It didn't budge.
He pulled out his phone and found the landlord's number. A middle-aged woman named Li. Her voice was a little hoarse, and when she answered she sounded like she was in the middle of a mahjong game—tiles clacking in the background.
"Sister Li, quick question—did you come by the place yesterday?"
"No, I'm out of town. Why?"
"I opened the windows to air the place out yesterday. Came by today and they're all shut. Latches on."
Two seconds of silence on the line, then a tile hitting the table. "You didn't shut them when you left?"
"No, I opened all of them."
"Probably the wind," Sister Li said. "Those windows are old. A strong gust and they swing back on their own, the latch might slide into place. No big deal. Just open them again."
Cheng Shi wanted to say a latch doesn't slide in on its own—he'd tried it the day before, that thing was tight, you needed real force to seat it. But he said nothing. "Fine, I'll take care of it."
"Alright, go ahead and move in. Call me if anything comes up."
The call ended. Cheng Shi stood in the north bedroom a moment, pulled the latch open, and pushed the window up. Outside was the gray wall of the next building, too close for any wind to find its way in. He went around and opened the rest one by one. Latch up. Window all the way.
This time he was careful. Before leaving, he set a piece of paper on the living room windowsill—a scrap torn off the rental contract from yesterday. He folded it once and stood it up. If any wind pushed the window shut, the paper would get caught. Or knocked over.
He went downstairs to move his stuff. The van showed up. The driver helped carry the boxes and the fold-out bed upstairs, and Cheng Shi gave him a pack of cigarettes. The driver said, living alone, kid? He said yeah. This building's old, the driver said, cold in the winter? He said it should be fine, there's heating. After the driver left, he started unpacking.
Boxes opened one by one. Clothes into the wardrobe. Books stacked on the low table in the living room. Fold-out bed set up in the south bedroom. He worked all afternoon. At one point he went down to the corner store for a bottle of water, and when he came back he made a point of checking the living room windowsill.
The paper was still there. Standing. Untouched.
The window was open. The wind made the paper's edge tremble, but it stood steady—not caught, not knocked over. Cheng Shi let out a breath. He'd been overthinking it.
---
That evening he put sheets on the bed and lay down. He'd closed the south bedroom window, but left the latch off, a crack open for air. The living room and north bedroom windows stayed open. No one was sleeping in there anyway. Let the wind blow through the night.
He killed the lights. In the dark he heard the wind pouring through the living room and out through the north bedroom's opening, carrying a thin whistle. Six floors up, barely any traffic. Just a distant horn now and then, muffled like it was underwater.
He turned over and fell asleep.
Around two or three in the morning, he woke. Not because of a noise. He just opened his eyes, consciousness surfacing from a dream, and everything around him was still.
Then he heard it.
From the living room. Something made a sound.
He lay still, listening. A moment later. Another one.
Click.
Soft. Like metal catches meeting.
He sat up, bare feet on the floor. The floor was freezing. He walked to the bedroom door. The living room was dark, but he could make out a pale gray patch where the window was—streetlight bleeding in, tracing the window's outline.
The window was shut.
He went over and felt the frame. Aluminum. Cold. He felt around and found the latch. Seated in its slot. Tight.
He pulled at it. Stiff, but it came. He pushed the window open, and the night wind rushed in against his face. Cold. He closed it again. This time he didn't set the latch. Just left it resting closed.
Back to bed. Eyes shut.
Click.
Clearer this time. Coming from the north bedroom.
His eyes snapped open, staring at the ceiling. He hadn't closed that bedroom's door. A black doorway faced the living room. The sound came from in there. The metal click of a window latch. Click. Click. A few seconds apart. Unhurried, like someone trying it over and over.
He threw off the blanket and went. Crossing the living room, he felt along the wall, found the switch, and hit it. Harsh white light laid everything bare. The north bedroom door was open. The window was exactly as he'd left it—open, the wind puffing the curtain out like a raised sail.
The latch wasn't seated. It hung loose, swaying a little in the wind.
He went over, slid the window shut, and seated the latch. The curtain dropped and lay still against the glass. He stood in the north bedroom for half a minute. Nothing. Only his own breathing.
He shut the north bedroom door and went back to the south room. This time he closed that door too, though he knew it was useless. A wooden door doesn't stop anything. He lay back down, phone in hand, screen glowing: 3:17 a.m.
He debated calling Zhou Ming, then decided against it. At this hour he'd only wake his friend up too. He set the phone by his pillow, screen-down, and closed his eyes.
Some time later, hovering at the edge of sleep, he heard it a third time.
Click.
Right beside him. The south bedroom window.
He sat bolt upright as if electrified, whipping his head toward the window. Still closed. The crack he'd left was gone. The window was fully shut. Moonlight came through the glass, falling on the sill, falling on the little iron latch. Seated in its slot.
Cheng Shi stared at that latch for a long time. There was no one else in the room. The window had closed itself. The latch had set itself. He tried to convince himself it was the wind—the window hadn't been fully shut, a gust pushed the pane back, and the momentum carried the latch home.
But he'd tried that latch. It was tight. It took real pressure from your fingers to seat it. Could wind push a latch that tight?
He didn't know.
He got out of bed, opened the latch, and pushed the window up. No crack this time. Wide open. The night wind came in, the curtain lifting and brushing his arm. Cold.
He stood at the windowsill until the wind got to him, then climbed back into bed and pulled the blanket up. He left the south bedroom door open. He didn't dare close it. There was faint light in the living room—at least he could see the outline of the doorframe. It made him feel a little safer.
No more sounds. When he woke the next morning, it was already light. Sun came through, making the curtain glow. He sat up. First thing he looked at was the window.
Open. Unclosed. The wind swelled the curtain now and then, flashing the blue-white sky beyond.
He let out a breath and went to wash up. He'd slept badly, dark hollows under his eyes. He checked the mirror, splashed his face, and went downstairs for buns and soy milk.
Coming back, he deliberately looked into the north bedroom. The sun was fine. The living room was warm, fine dust floating in the air. Just like yesterday.
Maybe he really was overthinking it. In an old complex, old windows swinging shut in a strong wind—that wasn't so strange. The latch he couldn't explain. But maybe there was some physical reason for it. He just didn't know.
---
That night he deliberately opened every window, the south bedroom included. He told himself: one more night. If he heard the sounds again, tomorrow he'd buy some window stops and clamp them from outside.
He lay down, eyes closed. Sleep came slowly this time. His head kept replaying those sounds, but he forced himself to relax, counting breaths, sinking slowly into the pillow.
In the middle of the night he woke.
Not a sound this time. The cold.
It was cold enough to curl him up tight, blanket pulled snug, the chill still crawling down his back. Half-asleep, he reached out and felt the air beside his neck. It was low—at least five or six degrees colder than when he'd gone to bed. He hunched his shoulders, lifted the blanket a crack to check the window, and saw it.
The south bedroom window was sealed shut. Moonlight lay flat and white on the glass.
And standing in front of the window: a person.
A figure with its back to him, standing at the windowsill. Its shape was blurred, outlined in dark against the moonlight. Both hands were extended, resting on the two sliding panes, drawing them together slowly, so slowly.
Cheng Shi's throat tightened, something lodged in it, no sound coming out. He went rigid in bed, blanket pulled to his chin, not daring to move.
The back looked ordinary. Average height. Slightly slumping shoulders. Dark clothes. It closed the window slowly, carefully, as if afraid of making a sound. The two panes crept toward each other, the gap narrowing, until they met flush.
Then it raised its right hand, pinched the little iron latch between its fingers, and pressed it down.
Click.
Not a loud sound. But in the dead night, clear as anything.
The figure stood at the window a moment without turning. Cheng Shi watched its hand drop back to its side. Its posture was strange. Back a little hunched, head low, like it was staring at the floor. Or waiting for something.
What was it waiting for?
Cheng Shi felt his heartbeat slamming against his ribs—thump, thump, thump—each one rattling his bones. He tried to breathe shallower. Tried to keep the blanket from trembling. But his hands were shaking, and his teeth were chattering softly.
The figure moved.
It turned around.
Cheng Shi shut his eyes. He didn't know why he closed them. Instinct, probably. Like when he was a kid hiding under the blanket, certain that anything outside stopped existing if he couldn't see it. He squeezed them shut, straining, colors swimming behind his lids.
He heard footsteps. Soft. Step by step, from the window, past the foot of the bed, past the bedroom door. Then gone.
He opened his eyes. The doorway was empty. The living room was a black hollow, nothing there. He whipped his head around to the window. Shut. Latched. Moonlight on the glass. Just like before.
He collapsed onto the bed, cold sweat soaking through his pajamas. He stared at the ceiling, heart still hammering. He reached for the light, then pulled his hand back. He was afraid that when the light came on, that thing would be standing at the head of the bed.
He didn't know how he finally fell asleep. Maybe he was just too tired—his body gave out while his mind was still running. When he woke, it was full daylight, the sun bright enough to sting his eyes.
He sat up. First thing: the window. Open. Wind lifting the curtain with a rustle. The latch was open, hanging loose.
Cheng Shi sat on the bed for a while, staring at nothing. He wanted to tell himself last night was a dream. But he knew it wasn't. It had been too real—the sound of fingers pressing the latch down, the faint tremor of the floorboards as footsteps passed the foot of the bed. He remembered every bit of it.
He called Sister Li.
"Sister Li, can I ask—who was the last tenant?"
"Why are you asking out of nowhere?"
"Nothing. Just curious."
There was a silence on the line. "A man. Early thirties. He stayed less than six months before he left."
"Why did he leave?"
"Said it was a job transfer," Sister Li said. "Broke the lease early. Didn't get his deposit back."
"Which room did he live in—the south one or the north one?"
"The south one. It's bigger."
Cheng Shi held the phone without speaking. Sister Li asked what was wrong. He said nothing, just asking. After he hung up, he stood in the living room for a while. The sun fell across his bare feet, but his toes felt cold.
He walked to the south bedroom window and touched the latch. Iron. Cold. A touch of rust. He pushed it in and pulled it out. In. Out. Click. Click. The exact sound he'd heard at night.
"You lived here six months," he said to the window, his voice low. "You closed the window every night, didn't you?"
The window didn't answer. Wind came through, lifting a corner of the curtain, letting it fall back.
---
On the third night after moving in, Cheng Shi bought window stops—small iron clamps that hold the window from outside, nailed to the frame to lock the pane in place. He nailed two onto the south bedroom frame, one high, one low. His hand shook as he worked. The hammer nearly caught his fingers.
On the fourth night, he didn't hear the latch.
The fifth night, nothing either.
On the sixth night, deep asleep, he woke without warning.
The room was silent. Not a sound. The window was shut properly, the stops holding, nothing moved. But he was awake anyway, eyes open on the ceiling, feeling that something was wrong.
He sat up. In the doorway stood a person.
A back turned toward him in the doorway, shoulders slightly hunched. It just stood there, utterly still. Moonlight came through the living room window, tracing a gray-white edge around its body.
Cheng Shi looked at it, and his throat started closing again.
The figure shifted. It turned to face him. But he still couldn't make out its face. Just a gray smear, no features he could place. All he could sense was that it was looking at him.
Then it spoke.
The voice was cracked, dry, like a throat that hadn't seen water in a long time. "You... nailed... the window... shut..."
Cheng Shi went rigid. He opened his mouth. No sound came.
The figure took a step forward. Then another. It reached the foot of the bed and stopped. It could speak. It could move. It had far more awareness than Cheng Shi had assumed.
"You have to... keep the window open..." the voice said. "You have to..."
"Why?" Cheng Shi finally forced out, his voice hoarse, not sounding like his own.
The figure paused. It lowered its featureless head, as if thinking. Or remembering. "Back then... I didn't understand either... by the time I did... it was too late..."
"Understand what?"
"Everyone who moves in... has to open the windows... let the old air out... but..."
It stopped. Cheng Shi heard his own heart pounding—thump, thump, thump—hard enough to hurt his chest.
"But what?"
"But the old air that leaves..." the voice said. "...has to find somewhere to stay..."
Suddenly Cheng Shi understood.
It wasn't trying to shut the windows. It was shut out of them. Every tenant came in and opened the windows to air the place out, and the old air was blown out of the walls, the floorboards, the furniture—but it couldn't leave the apartment.
When the tenant closed the windows and slept, it had to find somewhere to stay. So it moved into a room and became the new old air. The next tenant came, opened the windows, blew it out, and it found somewhere to stay again.
It had been circling this apartment the whole time.
The last tenant had lived here six months, getting up in the middle of the night to shut the window. Not because he chose to. After he became the old air, his body still remembered the living—and drove him, out of instinct, to close the window properly.
"You..." Cheng Shi's voice trembled. "You're the last tenant?"
The figure didn't answer. It just stood at the foot of the bed, hands at its sides.
"You have to... keep the window open..." it said again. "Open... or... you'll become..."
Cheng Shi threw off the blanket, hit the floor barefoot, and ran for the door. When he passed through the figure, it was like pushing through a cold fog—no real mass, but the chill sank into his bones and made him shiver.
He burst into the living room and shoved every window open. Wind rushed in, slapping across his face. He stood in the middle of the room, gulping for air, the cold pressing his pajamas against his skin. He didn't care.
He looked back at the south bedroom doorway. The figure was still there, standing at the threshold, not stepping out. Facing the living room. Facing Cheng Shi. It stood just inside the line of the door, not one step beyond.
And Cheng Shi realized: it couldn't leave that room.
It was sealed in the south bedroom. The last tenant had lived there. Once he became the old air, he was trapped in that room.
All it could do was shut that window. Pace that room. In that cramped, south-facing, sun-drenched room, wait year after year for the next person to move in and become its kind.
Cheng Shi retreated to the corner of the living room, back to the wall, watching. It stood in the doorway, unmoving. Moonlight fell across it, and it wavered—like a wisp of fog the wind pulled apart, then let gather again.
"You... don't stay in that room..." the cracked voice drifted out of the bedroom. "Live in the north one... the north one and you'll be fine..."
Cheng Shi stood against the wall, watching the figure fade. It stepped back, receding into the darkness of the bedroom. Then he heard the window latch sound once. Click.
He stood in the living room all night without sleeping. All the windows open, wind pouring in from every direction, freezing him through. At dawn he called the landlord. He said he wasn't renting anymore. Sister Li asked why. He said he couldn't settle in. Forget the deposit.
He moved out that same day. The boxes he'd never finished unpacking went back in the van. While the movers worked, he stood downstairs and watched that sixth-floor south window. The wind pushed the curtain out, fluttering beyond the window like a hand waving.
---
Later, on Zhou Ming's advice, he found another place. North-facing, on the fourth floor. He opened the windows to air it before moving in, as always. But this time he stayed in the apartment all night, lights on, watching every window.
The windows didn't close.
His first night there, he slept well. His second night too. On the third night he woke in the small hours to use the bathroom. Passing through the living room, he heard a very soft sound.
Click.
Not from his place. From next door.
Cheng Shi stood in the living room, pressed against the wall, and heard the latch of the next apartment's window click once. Then again. Click. Click.
Cheng Shi stood in the living room a moment longer. Then he went back to bed.
The latch next door kept clicking. Click. Click. Unhurried, like someone testing it over and over.
He pulled the blanket over his head and closed his eyes.
Outside the window, dawn was nearly breaking.