The Demon in the Walls
Abaddon x Reader
Warning!:reader has the same age as his body
The Undervale Hotel never slept. Its pipes groaned with voices that weren’t mechanical, and every corner held a shadow too deliberate to be chance. You should have left weeks ago. Instead, you stayed. Something—someone—kept you tethered.
It was always the same: the flicker of a candle, the whisper against your thoughts, the sensation that the air itself was leaning closer. And then—him.
Abaddon.
He stepped from the dark like it obeyed him, the borrowed body of a boy cloaking the depthless hunger of a demon centuries old. His gaze, too sharp for his false youth, pinned you where you stood.
-Still here?His voice was a velvet coil, half-mocking, half-curious. “Most mortals run screaming after the first night. But you… You walk these halls as though you’re waiting for me.”
You swallowed hard, though your heart betrayed you with its quickening rhythm. “Maybe I am.
His smile was wrong on a child’s face, but the weight of it—ancient, knowing, dangerous—made your breath falter. He leaned close, shadows curling like smoke around your shoulders.
-You know what I am,he murmured. “You’ve seen the claws behind the curtain. And still you linger. Tell me, little wanderer… is it bravery that keeps you near me, or the thrill of touching what you shouldn’t?”
The walls creaked, lights dimming as if the hotel itself strained to hear your answer. And though terror coiled in your chest, you realized the truth in your silence: you didn’t just fear him.
Abaddon’s grin widened, sharp as a blade. His hand hovered near yours, never touching—just close enough for the heat of his presence to sear.
-Careful,he whispered, voice dropping to a low growl. “Keep looking at me like that, and I might start to believe you’re mine.”
In next day
You felt him before you saw him—like cold smoke curling into your lungs. Then he stepped from a shadowed corner of the corridor, eyes glinting, a grin that didn’t belong on a child’s face stretching too wide.
-You didn’t answer me last night,he murmured, voice wrapping around your ribs like silk binding steel. “Afraid of me… or afraid of yourself?”
You swallowed, trying to stand your ground. “Both.”
Abaddon laughed softly, the sound dry and ancient. -Honesty. Rare. I like that.
He paced around you in slow circles, shadows bending with him, as though the hotel itself leaned to his will. His voice was a whisper and a thunderclap at once.
-Let’s play a game.”
The hallway stretched impossibly long behind him, doors flickering in and out of existence. He stopped, tilting his head at you with a predator’s curiosity.
-I’ll open one door. Behind it lies either freedom… or me.” His grin sharpened. “If you choose wrong, you’re mine.”
You exhaled, steadying yourself. “And if I choose right?”
His eyes glowed, fire caged behind them. “Then you walk away tonight. But…” He leaned closer, his presence suffocating, intoxicating. “…we both know you don’t want to choose right.”
The silence pressed in. The floorboards groaned. Abaddon extended a hand—long, clawed fingers breaking through the illusion of boyish flesh for the briefest moment.
-Door one, he whispered, gesturing to your left. “Or door two…” The one to your right shuddered, a low growl vibrating behind it. “Choose, little mortal.
And beneath the terror, the undeniable truth clawed at your chest: a part of you wanted to pick the door that led straight to him.
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Hi I hope you like it!Sorry that I don’t wrote something!I just been busy!