【Japanese Horror】When the Koinobori Moves | A Haunted Kaidan Tale
The Carp That Swims in the Sky
In Japan, there’s a seasonal tradition that colors the spring sky—koinobori, or carp streamers.
They’re flown for Children’s Day, also known as Tango no Sekku, a day to pray for the healthy growth and success of boys.
Each one swims proudly in the wind, like a carp climbing a waterfall, carrying hopes into the sky.
But have you ever felt something strange when you looked at them?
Like they were moving even when there was no breeze?
Like they were… watching you?
Let me tell you a little story.
It happened not far from where I live.
And it all started with one koinobori, quietly swaying outside a balcony.
Something Swimming Across the Balcony
There’s this apartment complex across from mine.
On the seventh floor, at the far corner, a single koinobori had been hanging.
The first time I saw it was near the end of April.
It’s around the time people start putting up their streamers for Children’s Day.
But that one… it was up early.
And it moved—just a little too much.
Even on days with barely any wind, that lone carp kept swaying.
Not violently—just enough to feel… off.
It didn’t flap like fabric.
It drifted—like it was swimming.
At first, I didn’t think much of it.
But one morning, I looked up and felt it:
That strange sensation, like its eye was staring straight at me.
I told myself it was just my imagination.
But after that, I couldn’t help it.
Every day before school, my eyes went to that balcony.
I just had to check.
Some days, it hung upside down.
Other days, it twisted wildly in the still air, like it was climbing toward the sky.
One evening, I climbed the stairs to the seventh floor.
No nameplate. Curtains drawn. No signs of life.
I rang the bell. No answer.
From the stairwell, I glanced up again.
Just for a second… I thought I saw a shadow inside its mouth.
Something dark, tucked away in the hollow space.
When I blinked—it was gone.
But I couldn’t shake the feeling.
Then came the night after a long spring rain.
The air was still damp, the night dead quiet.
I don’t know why, but I found myself going back up those stairs.
This time, I noticed something new—
wet footprints.
They started near the door and led toward the balcony.
I leaned in.
A gust of wind hit my face.
There’d been no wind before.
The koinobori snapped to life—twisting, turning—until its face met mine.
I froze.
Its eyes weren’t painted anymore.
They were alive.
They were watching me.
Inside its mouth, something moved.
A shape. A face.
And it looked… like mine.
I wanted to run—but then, I heard it.
A whisper.
Right next to my ear.
“You could swim too, you know.”
I turned around.
No one was there.
Just the koinobori, quietly floating—
like it was looking up at the sky.
Maybe It Doesn’t Just Carry Wishes
Koinobori are meant to carry hopes.
They’re flown to wish for strength, success, and a bright future.
But what if that wind…
doesn’t only lift up dreams?
What if it pulls something else with it—
something wandering, something lost,
something that was never meant to rise?
Even now, somewhere out there,
a koinobori might still be floating in the breeze.
Quietly watching someone.
Waiting to take something with it.
This story is a work of fiction. Please enjoy it as entertainment and use it as an opportunity to learn about the fascinating traditions of Japanese culture.
Are there any traditions in your culture where decorations are used during seasonal events or festivals?
Feel free to share in the comments—we’d love to hear about your customs!
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- The Shrine That Appears Only on New Year’s Day
This story was brought to you by Haunted Kaidan Tales.
Welcome to a world of Japanese ghost stories and eerie folklore.
Feel free to explore more chilling tales at your own pace.
Some stories were meant to be forgotten—
and yet, they still whisper to those who listen…