I hastily ran back to the apartment building. The elevator was on the 12th floor and stayed there for quite a long time. I gritted my teeth and kicked open the door to the emergency staircases, climbing my way up.

I had never sweated this much in my life, nor had I climbed so many steps. I didn’t know how long it took to reach the 27th floor, but my legs were shaking when I got there. The door to Mr. Song’s apartment was open. I gasped for my breath and calmed down. Then, I cautiously entered the suite.  

As soon as I entered the apartment, a stench overwhelmed me. I had no time to think and rushed to the balcony. The window was open. Although there was no wind, the window panels were moving, which created a rhythmic squeaking sequence. It somewhat sounded like the ticking sound of a...