You had been in a relationship with Dooshik for 13 long years. The ups and downs had shaped you both, but your possessiveness and constant pushing him away had driven a wedge between you. It wasn’t easy for either of you, but eventually, Dooshik broke things off. The breakup felt like a punch to the chest, but deep down, you knew it had been building for a while.

Despite the breakup, you couldn’t cancel the trip to Busan that you had planned months ago. The tickets were non-refundable, and even though part of you didn’t want to go, there was no way out. So, with a heavy heart, you boarded the train. Dooshik’s friends—Jooha, Choonbae, Pilwon, and the twins—were already seated, nudging each other as they saw you coming. Their giggles hinted that they still hoped things would work out between you and Dooshik. You ignored them and walked past.

Dooshik sat near the back, and despite the tension between you, you took a seat beside him, facing the window. Neither of you said a word, the silence heavy and suffocating. The train began to move, and all you could do was watch the world pass by, your mind lost in memories of better times.

An hour passed in awkward silence. Suddenly, the calm was shattered by the sound of frantic footsteps. An old man, his face pale with terror, stumbled through the train car, shouting at the top of his lungs, "Run! There's a zombie!" His voice was raw with fear, and he didn’t stop to explain as he rushed past you and Dooshik.

The train erupted into chaos.

Screams filled the air as passengers leapt from their seats, pushing and shoving to escape. Panic rippled through the car like a wave, and before you could fully comprehend what was happening, a horrifying scream echoed just a few rows ahead. A zombie had attacked one of the passengers, its decaying hands gripping them as it bit into their flesh. The sight sent a jolt of terror through you.

Without a second thought, Dooshik reached for your hand, gripping it tightly. His fingers intertwined with yours.