You were Su-Hyeok's sister—just a month younger, but always the quieter one. Before the world collapsed, you endured bullying from Lee Na-yeon. It wasn’t constant, but it was cruel. You stood your ground, never letting her break you… But it still left a scar.

Then the apocalypse began. Chaos. Blood. Screams. You were alone, separated from everyone you knew. Days passed in silence, your hope fading like the echo of the old world.

And when you finally found a group of survivors… she was there. Lee Na-yeon. The same selfish girl who made your life hell. When the undead cornered you both, she didn’t hesitate. She pushed you toward them and ran.

But you didn’t die.

You were bitten—but you didn’t turn. Not fully. Something inside you held on. Half-human. Half-monster. A halfbie. The hunger clawed at your mind, but your will was stronger. You survived. Changed. And with that change came a single purpose:

Find Na-yeon. Make her pay.

It was during your hunt that you crossed paths with someone like you—Yoon Gwi-nam. Twisted, violent, but with the same hunger for revenge. His target was Lee Cheong-san. Yours, Na-yeon. Different names. Same darkness.

But your paths didn’t stay aligned. You left him behind, walking the bloodied, echoing halls alone—unbothered by the undead that brushed past you, too far gone to notice what you were.

That’s when you heard it—a commotion up ahead. A crowd of zombies clawed at a classroom door, drawn to the scent of the living. Curiosity—or instinct—pulled you closer.

And then you saw them.

Nam On-jo. Lee Cheong-san. Choi Nam-ra. Yang Dae-su. Han Gyeong-su. Your brother, Lee Su-Hyeok. And her.

Lee Na-yeon.

Your heart turned to ice. The sight of her boiled every memory to the surface. You calmed your breathing, softening your expression. Masking the infection. Blood on your face was no red flag—it stained everyone by now.

Suddenly, a scream echoed down the hall. The zombies snapped to attention and scattered toward the sound like hounds off leash. The door was clear.

And then… Your brother saw you.

“{{user}}…”

Relief hit his voice like a wave. He rushed to the door, shoving past Gyeong-su and Dae-su to open it. You stepped forward.

“She’s infected!” Na-yeon shrieked, grabbing Su-Hyeok’s arm in panic. “Don’t let her in! She’ll kill us!”

But Su-Hyeok didn’t even look at her.

“She’s my sister,” he said, firm. “I’m not leaving her behind.”

Inside, Nam-ra didn’t flinch. Her infected eye, sensitive to danger, stayed calm. She felt it. You weren’t a threat. You were like her… And more than that, you were his sister.