Codex Null: Simulation Through Madness

The next day arrived.

Noel, appearing calm, unchanged, as if he hadn't uncovered any disturbing truth the day before, spent the morning just like usual.

Until noon.

After finishing his preparations, dressed in some of the finest clothes he owned, he stepped out of his room.

"Mmm, Noel…? Where are you going so early…?"

A soft, drowsy voice, slow and sensual, floated up from behind him.

Noel's steps paused.

He turned his head slightly.

Lilith stood there, rubbing her eyes with the back of her hand. Her long black hair tumbled in messy waves past her waist, sticking to her skin in places. She yawned lightly, her lashes fluttering.

Noel's gaze narrowed.

Unlike her usual sleepwear, silk shorts and a camisole, today, she wore only a thin, glossy camisole that barely reached the top of her thighs.

Nothing underneath.

The fabric clung to her skin, offering an unfiltered view of her long, pale legs… the curve of her thighs… and the faint glimpse of what should've remained hidden. Her breasts swayed gently as she moved, the deep white valley between them starkly visible through the sheer fabric.

She looked like she had stepped straight out of a dangerous dream. And she was looking at him.

Noel exhaled slowly through his nose. A flicker of something unreadable crossed his face.

Until yesterday, none of this would have mattered.

He had noticed her behavior, of course. The subtle provocations, the way her eyes lingered.

But he hadn't been conscious of it.

He hadn't let himself care.

But now?

After what he saw in the simulation… after witnessing how far her feelings truly went, this sudden, dramatic change wasn't just another habit of hers.

This was a message.

And he understood it instantly.

Even then, none of that really mattered.

What did matter… was something else entirely.

Their house had a ground floor, and two more levels above.

Noel's room, and Lilith's, were both on the third floor.

His adoptive parents? They almost never came up.

It could be counted on one hand how many times they'd stepped foot upstairs.

He had long been suspicious of that.

And now, it clicked.

It was arranged like this… so that Lilith, their master, could be more comfortable.

Their real identity?

The nature of their relationship with her?

He still didn't know.

But after yesterday's simulation… he knew one thing with certainty:

They worked under her.

Again, even that didn't matter.

Not what she did to him in that future.

Not how she pushed the him of the simulation to the point of suicide.

If he were to be angry at anyone — then it would be at himself.

No. The reason his eyes narrowed now was something else.

Something simpler.

She was just waking up now.

What exactly was she doing all night?

How many things didn't he know about her?

His younger sister.

His Lilith.

That thought lingered like a cold draft through his mind.

"Noel?"

Lilith's voice cut through the silence. She tilted her head slightly, noticing how he'd spaced out.

She might have been pleased — triumphant, even — if his gaze had lingered somewhere lower.

But the problem was, it wasn't.

His eyes stayed on her face.

On her eyes.

Not on her exposed skin.

Noel, pulled from his reverie by her voice, blinked once. Then, out of nowhere, he flashed her a grin.

"Well," he said casually, "I'm heading out to see my Selena."

"My girlfriend."

"Do you want to come?"

His eyes gleamed as he looked at her — glinted with something bold, dangerous. The kind of look that dared her to act.

It was subtle… but unmistakable.

A challenge.

One that threatened to make her move earlier than she had in the simulation.

Noel's mind might have been a chaotic storm, but even then, he had always strived to be the calm in its center — clear-headed, deliberate.

And now, with the Codex Null, that control should have only sharpened.

But were decisions always guided by logic?

By reason?

At this moment, something stirred in him.

Something he rarely felt.

Emotion.

And he acted on it — simply, and without restraint.

Especially when he saw it.

Lilith's eyes glowed faintly, darkly. Her jaw clenched, and her fingers curled into a tight fist at her side.

There was an aura around her now — thick, suffocating.

The kind of pressure that would've made any ordinary person collapse on the spot.

But Noel?

His grin only widened.

"Lilith?" he said, his tone almost playful.

He mimicked her voice from earlier, down to the exact softness in her tone.

But this time, there was weight beneath it.

Something she couldn't read.

And didn't like.

Yet… she didn't move.

She just stared at him — wide-eyed, unblinking.

There was something different in him now.

And for a moment, Lilith barely recognized her brother.

His gaze didn't roam over her exposed body, didn't flinch at her provocations.

Instead, his eyes looked into her — right into her soul.

And for a terrifying second, it felt like he saw everything.

Her chest tightened. Her heartbeat grew erratic.

Her knees weakened slightly, a faint tremble running through them.

A flush crept up her cheeks — not just from embarrassment.

But from something… unfamiliar.

Something she couldn't name.

What's going on?

The thought echoed in her head as her eyes narrowed.

A bitter pang twisted in her chest.

Was this change in him… because of Selena?

Lilith quickly shook her head, pushing the thought down. Then, taking a step closer to him, she said, "It's our final year of high school. I'm pretty busy preparing for exams, so… just go alone this time."

Her tone was casual, her smile faint.

Noel gave no immediate reaction.

But his eyes, steady and unreadable, rested on her a second longer than needed.

Woke up at noon, and now suddenly diligent?

Busy… because of school?

He didn't say any of it aloud. He simply nodded and turned to leave.

Then—

She grabbed his arm.

"You forgot my morning hug," she said softly, like it was the most natural thing in the world.

And Noel stopped.

His eyes shifted toward her. Her lips were curved into that innocent, dangerous smile again.

He didn't say a word.

Instead, he pulled her close.

Her arms wrapped around his neck almost instantly, smooth and practiced. She pressed against him, and for a long moment, neither of them moved.

Then—

A slow, pleased breath escaped her lips, warm against the skin of his neck.

"Better," she whispered, voice still drowsy.