Horde of Zombies at the forest

Tall trees towered over the field; three figures stood before the forest’s edge.
One figure was named Mahadriya Alutista. He wore a dull brown cotton shirt and plain grey trousers that reached from his waist down to his ankles. Crimson irises gleamed within his sharp, fox-like eyes. Though his pale brown skin and build granted him a steady, powerful presence, his body trembled uncontrollably. His mind was clearly consumed by fear; anyone looking at him could tell instantly that while his body had matured, his mindset was far from ready.
Beside him was a knight, encased from head to toe in full, yellowish plate armor that completely concealed his face.
On his other side stood a girl named Mahadriya Suryawari. Dressed in a noble red tunic and a peacock-tail skirt that fell from her waist to her knees, her jet-black, curly hair flowed down her chest, exuding the undeniable aura of a villainess.
Deep within the shadows of the forest stood a vast crowd of people. But none of them were alive.
They were dead.
They were zombies.
And lurking among the horde was a monster... nope, something that looked almost human. His face and skin were a sickly pale yellow, and his irises were entirely white. Dull white hair drifted backward like moss swaying in a flowing stream, and a fearsome, crocodile-like array of teeth seemed fused directly with his mouth.
"Now... Attack!" the knight shouted.
As the knight's voice faded, the horde of zombies rumbled forward, surging out from behind the trees toward them.
"Don't kill them—just render them recessive!" the demon—the Carafiend—warned his undead minions.
The knight closed the distance in a flash. His blade swung in a clean arc, severing a zombie’s neck and sending its head tumbling to the ground.
Meanwhile, Alut’s face turned deathly pale. Cold sweat beaded on his skin before rapidly evaporating into thin air. Whatever courage he had managed to muster was instantly crushed by overwhelming fear. Suddenly, his second shadow vanished from beneath his feet and reappeared five meters behind him. Anyone who saw the shadow knew instantly what his next move would be.
"Ah, is he seriously the hero?" the Carafiend mocked with a sneer. "What kind of hero runs away instead?"
Suryawari's head snapped toward her elder brother, her mind darkening as raw fury eclipsed her thoughts.
"{You want to flee, coward!}"
"Don't flee, Alut!" the knight yelled.
But Alut's mind was entirely controlled by fear; he paid no heed to the knight's warning. On the other hand, pure rage had taken complete hold of Suryawari. Her chest opened dimensionally, revealing a glowing crimson fireball nestled within—no, it wasn't a fireball. It was a miniature crimson star.
"{I punish you!}" Suryawari screamed.
The crimson star leapt from her chest and shot straight toward Alut. At first glance, nothing seemed to happen to Alut's outer body when the star touched him. But in reality, his physical form was being simultaneously destroyed and regenerated down to its smallest particles at the exact same instant, flooding his mind with the agonizing weight of endless torture.
He tried to flee again, but his body refused to move. He could feel an immense force pressing down on him, crushing him from both the outside and within. An indescribable pain surged through his body from his head down to his feet, as a blinding crimson light consumed his entire vision.
"Let me flee!" Alut screamed.
"{Fight or infinite death?}" Suryawari demanded.
He had only two options, yet he forced a third into existence. "I choose to run!"
"{Fight or infinite death!}" Suryawari repeated coldly.
"Run!" Alut yelled back.
His vision and all his senses faded and reappeared simultaneously. He had never been cruel to his younger sister, so why was she doing this to him? The answer was simple enough, but his ego shielded his mind from accepting the truth.
"Come on, don't cower like a coward!" the knight shouted. "You're the hero, dude!"
"I never asked for any of this!" Alut barked back.
"The conditions: reality, the planet, physics itself. all of them chose you as the hero!" the knight insisted.
"Honestly, I want to lecture him too, but I'm a demon," the Carafiend sighed.
"I want to flee! Please, let me flee!" Alut cried.
The Carafiend knew Alut's mind was completely consumed by fear. Yet, showing him compassion would mean the failure of his mission. His objective was to awaken the hero—a task bestowed upon him by his Demon King, Lord Zomias. To ensure the mission's success, he was left with only one option: transform into his true, most powerful form.
"Pardon me... Lord Zomias," the Carafiend sighed.
His neck elongated upward, and two additional arms sprouted from his shoulders, their lengths eerily disproportionate. Anyone who laid eyes on him would feel as if they were gazing upon a terrifying monstrosity straight from the deepest depths of hell.
Now, Alut had no option left but to run was impossible. His only choice was to stand and fight—and finally, his body responded to his will. His legs trembled violently as he forced himself to take a step toward the Carafiend. Deep down, the Carafiend felt a pang of pity for the boy, but he could not afford to show it. If he gave in to mercy, his mission would fail.
In the blink of an eye, the Carafiend's massive fist slammed into Alut, sending his body flying through the air before crashing hard onto the ground. Every inch of his body was racked with unbearable pain. Yet he knew that if he didn't stand back up, the Carafiend would end his life. Gritting his teeth, he forced his trembling limbs to push against the dirt, struggling to rise while trying desperately to ignore the searing pain crawling beneath his skin.
While Alut focused on surviving his clash with the Carafiend, the knight and his younger sister fought off the horde of zombies. Their minds were focused entirely on the assault, devoid of any fear. The undead horde dwindled under their relentless attack—some zombies fell as the knight's sword severed their necks, while others shattered into dimensional glass shards the instant Suryawari touched them.
Unlike his sister and the knight, who fought without hesitation, Alut forced himself to muster whatever courage he had—not to show off, but simply to find an opportunity to flee. His bare hands clashed against the Carafiend's long, razor-sharp claws. Soon, there was no time left to dodge. His blood evaporated into thin air, crystallizing into fine red dust, while his body regenerated once more at the particle level, completely engulfed in agonizing pain.
His body trembled and collapsed to the ground. Whatever courage he had left crumbled into utter despair; he could no longer stand. With a touch of worry—or a cold imitation of it—his sister walked toward him quickly.
"{Do you need help?}" Suryawari asked.
He realized that the figure standing before him was no longer his gentle younger sister, but her terrifying alter ego. Unable to do anything else, he nodded in resignation. Instantly, Suryawari's hand plunged straight into his chest, right through his heart.
"Wh-what... are y-you... do-ing?" he rasped, struggling for air.
"{Shut up!}" Suryawari snapped.
Their bodies dissolved into two swirling spheres of light before fusing together in mid-air. Moments later, a single figure emerged from the radiance. His entire body glowed with pure light, adorned with a floating, ethereal shawl. It was the hero's ultimate form—the fusion of Alut and his younger sister.
"Ah, I can already feel the calculations for <Aura Drona> magic..." the Carafiend groaned. In an instant, the entire horde of zombies was wiped out. As the wave of agonizing pain crawled through his own body, he complained, "Come on, that's not how the script works! He hasn't even grown mentally, but we're already at the strongest form?!"
Fighting through the pain, he forced himself to rise and teleported back to the Demon Castle.
"Why are you beaten black and blue?" a deep voice echoed through the hall.
As the Carafiend looked toward the source of the voice, a imposing figure stood before him. Massive, crimson deer-like horns branched out from both sides of his head. A black cloak draped down from his waist to his knees, radiating an aura of pure, suffocating terror. His hands were completely skeletal—devoid of flesh and skin—exuding the heavy pressure of relentless torment. And where his head should have been, a bare skull burned within a crown of dark purple flames.
"Ah, Demon King Zomias," the Carafiend replied with a sigh. "Pardon me... the mission failed."