Note: I'm not the authour of this story. I've translated it from original Japanese into English. Please do NOT copy and paste it somewhere else on the web without my permission.
I heard this from my friend at college.
It's a common story but there was an apartment that had one room where no one stayed for very long.
Everyone left within one week of renting it.
The room was on the first floor in the corner of the building and you could reach it by climbing a flight of stairs with seven steps.
The landlord felt uncomfortable about the whole affair and it bothered him a lot, but one day he got a tenant who stayed well over a week.
That made the landlord feel happier but just to make sure everything was alright he went to the room to check on the tenant.
But no one responded to the landlord's knockings.
The landloard felt something was amiss and he rang up the police. When the police arrived they broke into the room together.
Inside, they found the tenant's dead body.
The cause of the death was unclear and to find out what had happened the police then went around asking for information.
They managed to talk to some of the previous tenants of the room but none of them was willing to talk about the room.
However in the end they managed to get one person talking. His story went like this:
Every night a child's voice was heard.
On the first night after the tenant moved in, the voice said:
'Oooone step Iiii've cliiiimbed...'
He wondered what it was but nothing else happened and so he just ignored it.
But the next day he heard the same voice say:
'Twooo steps Iiii've cliiiiimbed...'
On the thrid day it said: "Threee steps Iiii've cliiiiiimbed..."
And so it went on the same way, on the fourth, the fifth and the sixth day.
The voice was clearly getting closer.
There were only seven steps on the stairs.
All previous tenants ran away fearing what might happen if it reached the seventh step.
And it appears the only person who knows the answer to that is the dead tenant.