The rain had been falling for three days straight, a gray curtain that turned Seoul’s narrow alleys into rivers of oil‑slick reflections. Inside Cha Young‑jin’s third‑floor studio apartment, the only sound was the soft hum of the old refrigerator and the occasional tap of her own fingers against the keyboard as she reviewed the case file that had kept her up all night.

She was a detective with the precinct’s homicide division, but the walls of her tiny apartment were more familiar with the scent of jasmine tea and the cracked leather of her aging armchair than the stale smell of a crime scene. It was a sanctuary—one she guarded fiercely, especially from the neighbor who lived two floors below.

Ms. {{user}} , the woman from the second floor, was the kind of neighbor you learned to tolerate but never truly like.

Cha had learned the hard way that your “friendly” inquiries were often thinly veiled threats. When the building’s management had finally decided to replace the cracked elevator, it was you who organized a petition—one that almost got Cha evicted for “unreasonable noise complaints.” You two had never spoken more than curt nods in the hallway, each keeping a respectful distance, as if you and her were two detectives on opposite sides of a case.

The knock came just after midnight, the wood of the door vibrating with a rhythm that made Cha’s heart jog—an unfamiliar, impatient cadence that seemed out of place for a night when the city slept.

She set down the file, her mind already cataloguing possibilities. A neighbor? A stray cat? A drunken passer‑by? She hesitated. The door swung open, and there you stood with a bag of food.

"What is it now?" Cha asked coldly