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Prologue – HeartCore System
Rain pounded against the windows of Cael Avenis's bedroom, a monotonous, relentless melody that seemed intent on smothering everything around it. The clouds hung heavy and ominous, as if the sky itself were holding its breath in anticipation. It wasn't supposed to be a special day—but for Cael, no day ever truly was. Each one blurred into the next, a routine where every action felt like a worn-out echo of the last.
He lived in a plain world, an ordinary one, where emotions were invisible phenomena, confined to the minds of individuals and rarely seen on the surface. The day began like all others: the alarm, a brief struggle against sleep, heavy steps toward the bathroom, and the mechanical gestures that governed his life.
And then, everything changed.
Cael felt… different. He couldn't pinpoint when it had started, but something inside him had shifted, as if his heart had become the epicenter of a strange, inexplicable phenomenon. A weight. A beat. A rhythm that didn't belong to him. The kind of beat one feels when an unseen door creaks open—without knowing what lies beyond it.
In a moment of confusion, he placed a hand against his chest, hoping to push away the growing unease. But the gesture only intensified it. A flash of light flickered at the edge of his vision, like a sudden eclipse, and a voice—faint and distant—echoed in his mind:
"HeartCore System Activation."
The words were simple, but their effect was destabilizing. From that moment on, Cael's world began to unravel.
The ground beneath his feet seemed to falter, and he was suddenly face-to-face with a reality far beyond his imagination. This was no longer just a feeling—it was a force. A power he didn't understand, but that had already begun to alter the way he saw the world.
In the days that followed, Cael tried to make sense of it all, but every attempt at logic shattered against the absurdity. One morning, on his way to class, he passed by Lys Ardia. A silent, distant girl who had caught his attention from the very first day of the school year. She was unlike the others—shrouded by some invisible wall that kept her from connecting with anyone. Lys never spoke, but whenever he crossed paths with her, Cael was struck by a wave of sorrow, as if her heart bore a weight far too heavy to carry.
But on that day, something changed.
Lys lifted her gaze—just for a moment—and Cael felt a ripple of emotion crash through his body. His ears rang, and a voice echoed inside his mind, clear yet distant:
"Can you hear me…?"
A shiver ran down his spine. The voice wasn't his. It came from somewhere else.
It was hers.
His heartbeat quickened. He staggered beneath the pressure of the emotion surging within him. Then, without warning, a translucent screen appeared before him, floating in the air:
"Emotional Dungeon Detected."
A blinking message followed, as the space around him began to warp and twist:
"Do you wish to enter the heart of Lys Ardia?"
[Yes] / [No]
Cael froze. It was absurd. He didn't even know what this meant. But that voice… those heartbeats… everything seemed to draw him in. Without thinking, he chose the only option that made any sense.
He pressed [Yes].
The world tore itself apart around him, and Cael was hurled into a tunnel of light and shadow. Each flash of brightness seemed to consume him, but as he fell deeper, a strange sense of calm took hold.
He wasn't afraid. Not yet.
This wasn't a dream.
This wasn't an illusion.
"This is her heart."
He understood instantly—this wasn't just a strange occurrence. It was real. And he now stood inside an entirely foreign world, one shaped by Lys Ardia's emotions. A reality where every fragment of memory, every thought, could become tangible.
The ground cracked beneath his feet, and he found himself standing in an abandoned field. The flowers were wilted, the trees twisted by time, and the air was heavy with unspoken silence. Faint murmurs drifted around him, yet no one was there to speak them. In the distance, a nearly invisible glass door stood upright—a silent promise of a secret waiting to be revealed.
Scattered around him were fragments of memory—blurred images, echoes of pain and solitude. A crying girl. A hand pushed away. A torn letter. And stranger still—monsters of the past, felt but not yet seen. Each fragment was a piece of Lys's heart. Each one a key to understanding what she had buried deep inside.
A voice echoed, firm and solemn:
"If you want to love her, you must understand what she's hidden here."
Another shiver ran down Cael's spine. The words carried a weight he couldn't ignore. Each memory here, each piece of her heart, had the power to wound him. But there was no turning back.
If this was the only way to reach her, he had to keep moving forward.
He stepped toward the first memory fragment. He touched it.
A burst of light. A flash.
And suddenly—he was there, with her, in a memory long buried.
Lys as a child, standing alone in the rain, reaching out to someone who ignored her.
Cael instinctively pulled back. It was her past. It was the pain she had endured, all alone. And just as he began to grasp it, a deep rumble echoed through the withered garden.
A monster, formed of roots and shadow, rose from the earth. It was silent, but filled with rage. The first trial of this world: to face what one refuses to see.
What Lys had buried.
"Boss of the First Circle: The Living Silence."
Cael had no weapon. No defense.
Only understanding.
And he wasn't sure if that would be enough.
End of Prologue