rumpapotter
The Thirteenth Key
Thirteen years ago, Kang Min-jun's younger sister disappeared without leaving a single clue.
Everyone told him to move on.
He never did.
On a stormy night in Seoul, a mysterious black envelope appears in his mailbox. Inside is an antique key engraved with the number 13 and a chilling message:
"If you open the Thirteenth Door... don't trust the person waiting inside."
Moments later, Min-jun receives a text from an unknown number:
"The game begins tonight."
As he follows a trail of hidden clues, abandoned buildings, forgotten case files, and dangerous secrets, Min-jun realizes his sister's disappearance was only the beginning.
Someone has been watching him.
Someone knows the truth.
And someone is willing to kill to keep the Thirteenth Door locked forever.
One key. One missing sister. One secret buried for thirteen years.
Some doors should never be opened. 🔑