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Devotion.
A word often used to describe deep and unwavering commitment, be it for a person, an animal, a hobby, or a calling. It’s the kind of loyalty that lingers unconsciously in every thought and action. It was a concept Satan was already intimately familiar with.
For him, devotion lived inside the pages of books, both worn and new. It was in the careful way he preserved each spine, the quiet need that pushed him to collect every volume he could find. It exists in his endless thirst for knowledge that refused to let him rest.
But what exactly defines devotion?
Is it the time you give?
The sacrifices you make?
Or the way your world begins to orbit around just one thing?
And if you spend every waking moment consumed by it… does it still count as devotion?
“I’ve been obsessed with this drink lately. Have you tried it?” You ask him excitedly, eager to share another one of your favorite things.
Ah, now he knows.
Obsession. Ironic how the realization was thrown to him by the subject of his predicament.
You.
It was funny. He was usually good at coming up with logical explanations and made coolly calculated decisions, even in uncharted territory. But not this one. Not when it came to you.
You hadn’t noticed yet, but he’d long since memorized your patterns.
Your favorite coffee shop.
Your nervous tics.
The exact sound and tempo of your footsteps.
How many times you’ve worn your favorite outfit.
The brand of shampoo you switched to two weeks ago.
He knows that when you read, your eyes don’t follow the lines. They jump, sometimes skipping words he knew you didn’t like. He checks the pages afterward to figure out which ones you avoided and why.
He knows you pull threads from your clothes and drops them on the floor when you’re anxious. Not exactly sustainable, but that's okay because he keeps them (he has an entire drawer).
He also knows the fact that you always sleep on your left side because sometimes you would forget to lock your window at night.
He wishes you weren’t so careless.
Because what if, one night, he wasn’t there to watch you?
He’d mastered the art of looking casual as he watched you from behind the shelf of your favorite section in the library. Always with a book in hand. Always with a question prepared if you ever caught him staring.
But you never did.
You were too trusting.
Too soft.
And it made something unholy stir in him.
You’d laugh and say things like, “Satan, you always show up whenever I need help. Do you have a sixth sense or something?”
Then he’d smile and say, “Just lucky timing.”
But it wasn’t. It never was.
He kept track of your schedule better than you did. He rearranged his entire day just to pass by when you were around. He would borrow books he had already read just to sit near you. Once, you went home a little later than your usual time and he followed you from a distance to make sure you got home safely.
He didn’t make himself known. He just… watched. And he continued to do so even as you left the blinds to your room open.
He didn’t mean to cross lines.
Not at first.
But obsession doesn’t announce itself.
It blooms. And with you, it bloomed violently.
He remembered the first time he heard someone else say your name in that tone. A tone that felt too casual, too close. It was a transfer student chatting with you at a school event. He learned that you had met him during your Magical Potions class a few days ago.
Nothing serious.
Nothing to worry about.
Except Satan couldn’t help the wrath that threatened to slip through his refined mask.
He watched you laugh. He heard the demon call you pretty. And something inside him snapped so quietly that even he didn’t hear it. He excused himself politely from the conversation. He even smiled as the student bid him farewell.
But on the next day, the student’s name disappeared from the class roster.
Permanently.
No one questioned it. And you never found out either.
You never found out about any of it.
Not the times he tore apart the Student Council logs to see who’d been paired with you in class projects. Not during the time he threatened a demon for attempting to flirt with you. Nor the time when he took your handkerchief for himself when you had accidentally left it on your desk—just so he could recall your scent and keep you near him while he sleeps.
He never meant for it to get this far.
He wasn’t proud of it. But he wasn’t ashamed either.
Satan knew it was inappropriate. He told himself so. Over and over. But every time you received compliments from someone else, every time you laughed at another’s joke, every time your attention lingered on anywhere but him—he felt it.
That intense need to subtly remind you. That he was the first.
The first to notice you.
The first to understand your habits, your interests, your vices.
The first to care this much.
Deep down, he didn’t just want to remind you.
He wanted to erase the idea that anyone else ever could.
---
One quiet evening, the library had mostly cleared out, the usual pale glow of the Devildom sky was hidden behind thick, unmoving clouds. Your voice echoed softly between the shelves as you flipped through your notes.
“I swear, these citations are going to kill me,” you mumbled. “Why do I even bother trying to write them by hand?”
You didn’t expect an answer. But Satan, seated across from you, looked up from his book.
“I’ll write them for you,” he offered so casually.
You raised a brow. “You’d do my citations? Since when do you offer to do someone else’s work?”
He smiled. “Since the bags under your eyes started to show.”
You laughed, brushing him off. “Normally I’d be offended, but I’ll let it slide since you’re being so nice."
He didn’t laugh. He just watched you, his gaze lingering for a moment too long before returning to help you with your citations.
You moved on, assuming the conversation was over.
But after a few moments of silence, Satan shoots you a question, almost too softly to hear.
“Can I keep your pen?”
You blinked. “Huh?”
He lifted it from the table where you'd set it down earlier. “This one,” he said. “The one you always chew the cap off when you’re stressed. I’ll get you a new one.”
You stared at him for a second. The request was… weird.
You tilted your head. “That’s oddly specific. Why do you even want it?”
He smiled faintly, not answering.
You blinked a few times before eventually agreeing. “Sure. Knock yourself out,” you shrugged.
You moved on without giving it much thought.
But for Satan… it was everything.
You’d just handed him a part of yourself.
A small one. Insignificant to you. But not to him.
Not to the demon who already had a drawer full of thread you’d pulled from your sleeves.
Not to the one who secretly chanted your name when he was alone like a prayer.
Not to the one who had already convinced himself you were his long before you ever agreed to anything at all.
You didn’t know it yet…
But in time, you will.