Demon Lord reborn as The Hero's Child

Kōya’s body moved before his paralyzed mind could react. He rushed forward, dropping his blade in the dirt.

Seiya tried to straighten his posture as his son approached, his arm trembling violently. ”Kōya...”

”You’re hurt.”

Kōya dropped to his knees in the blood-soaked mud beside him, his hands hovering, afraid to touch him and cause more pain.

Seiya gave a faint, rattling laugh. ”You noticed?”

Kōya stared at him, his analytical mind shutting down. There was too much blood. Far, far too much blood to survive.

”Can you stand?” Kōya asked, his voice shaking.

Seiya looked out toward the distant, silent village. Then back at his son.

”I think...” He swallowed hard, grimacing in pain. ”I think I’d rather go home.”

Kōya immediately moved behind him, sliding his arm carefully around Seiya’s waist. ”Put your arm around my neck.”

Seiya did, his heavy, scarred arm draping over Kōya’s shoulders.

Kōya carefully, smoothly lifted him. Seiya’s immense, dead weight settled heavily against his son.

For a long moment as they began the slow walk back, neither of them spoke.

Then, Seiya smiled faintly.

”So...”

Kōya kept his eyes focused on the path ahead, adjusting his grip to keep his father upright.

”How was school?” Seiya asked.

Kōya looked at him, completely stunned. ”What?”

”The Academy.” Seiya’s voice was incredibly weak, but there was genuine, paternal curiosity lacing every syllable. ”How was it?”

Kōya stared at his dying father in absolute disbelief. ”You are asking me about school right now?”

”Of course.” Seiya smiled through the pain. ”Did you behave yourself?”

Kōya almost let out a hysterical laugh. ”You are bleeding out.”

”I noticed.”

”You could die before we reach the house.”

Seiya became quiet for a moment. Then he smiled again, ignoring the blood dripping from his chin. ”I asked you a question, Kōya.”

Kōya swallowed hard, looking straight ahead, fighting the tears. ”It was fine.”

”Just fine?”

”I made friends.”

”Good.” Seiya’s voice softened beautifully. ”Are they good people?”

”Yes.”

”Did they treat you well?”

”Yes.”

”Did anything happen to you?”

Kōya hesitated, the horrific memories of the bridge and the roof flashing through his mind. ”A lot happened.”

Seiya looked at him, his eyes sharp despite the fading light. ”But you are unharmed?”

Kōya nodded. ”Yes.”

”Then that is enough.”

Kōya glanced at his father, his heart aching. Seiya wasn’t asking for a tactical report about the battle in the woods. He wasn’t asking about his own catastrophic wounds. He was asking if his son had been safe.

Even now.

Especially now.

They continued walking in slow, agonizing steps.

After a while, Seiya spoke again, his breath hitching. ”Your mother is going to be so happy when she sees you.”

Kōya’s grip tightened around his father’s waist. ”I need to find her.”

”We will.” Seiya’s voice was gentle, a promise. ”We’ll find her.”

Kōya nodded. He didn’t notice how incredibly faint his father’s voice had become. He refused to notice.

They finally reached the back door of the house. Kōya carefully helped Seiya inside, guiding his heavy frame toward the dining room.

”Sit here,” Kōya instructed softly, pulling out a heavy wooden chair.

Seiya lowered himself into the seat with a long, slow exhale of pain.

Kōya crouched beside him. ”Stay here. Do not move.”

Seiya smiled weakly. ”You sound exactly like your mother.”

Kōya stood up to search for medical supplies. Then, he noticed the table again.

The meal.

His eyes widened slightly. In the panic, he had completely forgotten about it.

”You made dinner before they came?”

Seiya looked toward the table, his eyes soft. ”No.” He smiled. ”Your mother did.”

Kōya stared at the food. The steam was finally beginning to fade. ”But...”

Seiya reached a trembling hand toward the table, gesturing to the opposite chair.

”Come here.”

Kōya slowly walked over and sat opposite him.

Seiya looked at the meal, a fond expression crossing his battered face. ”Your mother makes very tasty dishes.”

Kōya gave a faint, tight smile. ”She does.”

”You should eat.”

”I don’t feel hungry.”

Seiya looked at him. ”Kōya.”

The tone was incredibly gentle. But it carried the absolute firmness of a father.

”Eat.”

Kōya looked at his father’s face. Then at the food.

He slowly picked up his wooden spoon.

Seiya smiled, satisfied. ”That’s better.”

They began eating.

For a little while, the horrific world outside the walls completely disappeared.

There were no demons hunting in the woods. There was no invasion. There was no blood soaking the floorboards. There was no burning battlefield or lost friends.

There was just a father and a son, sitting at a wooden table. Eating dinner.

Kōya took a small bite. ”It is good.”

Seiya smiled through his pain. ”I told you.”

”She made too much.”

”She always does.”

Kōya looked at the empty chair sitting directly beside them. His mother’s chair. ”She expected us to eat together tonight.”

Seiya’s smile became overwhelmingly soft. ”She always did.”

Kōya forced himself to continue eating. Seiya watched him intently.

”You’ve gotten thinner,” Seiya noted.

Kōya stopped chewing. ”Have I?”

”Yes.” Seiya shook his head slightly. ”You’re supposed to eat more. You burn too much energy.”

”I eat enough.”

”You’re a growing boy.”

”I have already grown.”

”You can still grow.”

Kōya smiled faintly, looking down at his bowl.

For a few seconds, Seiya simply looked at his son. There was immense pride shining in his fading eyes. And something else. Something heavy that Kōya couldn’t quite identify.

”You really have grown,” Seiya whispered.

Kōya lowered his spoon, resting his hands on the table. ”I wanted to become stronger.”

Seiya nodded slowly. ”I know.”

”I wanted to become strong enough to...” Kōya stopped, the words catching.

Seiya waited patiently.

Kōya looked away toward the window. ”Nothing.”

Seiya smiled gently. ”You don’t have to tell me everything.”

Kōya looked back at him. ”But someday, I want to—”

Seiya suddenly coughed. It was a wet, violent sound. A thick line of blood appeared at the corner of his mouth, dripping onto his chin.

Kōya immediately stood up, his chair scraping loudly. ”Father!”

Seiya raised a trembling hand, waving him off. ”I’m fine.”

”You’re not.”

”I know.”

Kōya froze.

Seiya looked down at the table. The food was still there. Still warm. He picked up his spoon and forced himself to take another bite.

”It’s good.”

Kōya slowly sat down again. His expression remained incredibly tense. He watched his father’s chest carefully, tracking every shallow breath.

Something felt profoundly wrong. He knew it. But his brilliant mind couldn’t identify exactly what was failing. His tactical concentration was entirely shattered by grief, physical exhaustion, relief, and terror.

To accurately perceive the true condition of a soul required absolute focus. And Kōya’s mind simply could not gather itself enough to look beyond the bleeding physical body sitting in front of him.

He didn’t notice the incredibly faint, golden light beginning to softly separate from Seiya’s form. He didn’t notice that his father’s soul was already beginning to loosen its grip on the mortal coil.

But Seiya did. He knew exactly how much time he had left.

Seiya leaned back slightly in his chair, wiping his mouth. ”Kōya.”

”Yes?”

”There is something I wanted to give you.”

Kōya looked up. ”What?”

Seiya smiled, a nostalgic light in his eyes. ”I’ve had many adventures.”

Kōya raised an eyebrow, forcing a small smile. ”You never tell me about them.”

”I know.”

”You always say you’re going to tell me later.”

”I suppose I do.” Seiya chuckled, a wet, rattling sound. ”Maybe someday.”

”Maybe.”

Seiya’s expression became far more serious. ”There was one thing I kept specifically for you.” He looked toward the floorboards on the other side of the house. ”I wanted to give it to you when you finally returned from the Academy.”

Kōya followed his gaze. ”What is it?”

”A weapon.”

Kōya’s eyes sharpened instantly. ”Your weapon?”

Seiya nodded. ”One of them.” He smiled faintly. ”I’ve had many weapons over the years.”

”I thought Heroes only wielded one legendary sword.”

Seiya laughed softly, wincing as it pulled his chest. ”People like simple stories.”

Kōya almost smiled.

Seiya continued, his voice dropping. ”There are many things I could tell you about my adventures.” He looked deeply into his son’s eyes. ”But not tonight.”

”Why?”

”Because a man should discover some things for himself.” Seiya pointed a weak, trembling finger toward a specific floorboard in the corner of the room. ”Under the floor.”

Kōya looked toward it.

”There you’ll find my sword.”

Kōya stared at him, the weight of the moment settling over him. ”Your sword?”

Seiya nodded slowly. ”It belongs to you now.”

Kōya couldn’t speak.

Seiya’s eyes softened completely. ”Take it.”

Kōya nodded slowly, a lump forming in his throat. ”I will.”

”And use it.”

”For what?”

Seiya looked directly into his son’s dark eyes. ”To bring your mother home.”

Kōya’s expression shifted from grief to absolute, cold resolve.

Seiya’s voice became quieter, the strength finally leaving him. ”Kōya...”

”Yes?”

”There is only one request I have from my son.” Kōya leaned closer to listen. ”I’ve never asked you for much.” Seiya’s scarred hand rested flat on the wooden table.

”But I want you to do this for me.”

Kōya’s throat tightened.

”Save your mother.”

Silence filled the room.

”Get Mizuki back from them.”

Kōya looked at his dying father. ”I will.”

Seiya smiled. ”I know you will.”

Kōya lowered his eyes to the table. ”You don’t have to worry.”

”I know.” Seiya’s voice was barely an exhale. ”But I still wanted to hear you say it.”

Kōya looked directly into his father’s fading eyes. ”I promise.”

Seiya smiled, satisfied. ”Good.”

For a while, neither of them spoke.

Outside, the heavy evening rain had finally begun to fall. Soft, rhythmic drops tapped gently against the glass windows.

Seiya looked at his son. Then, he said quietly, ”Kōya.”

”Yes?”

”I know there is a terrible darkness inside you.”

Kōya’s body went completely, rigidly still.

Seiya continued, his voice devoid of any judgment. ”I’ve always felt it.”

Kōya didn’t know what to say. His father wasn’t reaching for his sword. There was no fear in Seiya’s eyes. Only immense warmth.

”But you are our child.” Seiya placed a hand against his own chest. ”You are Mizuki’s son.” He looked at Kōya. ”And you are mine.”

Kōya’s eyes began to sting.

Seiya smiled brightly. ”You carry something from both of us.” His fist pressed gently against his heart.

”Whatever ancient darkness is buried inside you...” He smiled. ”...don’t let it decide who you are.”

Kōya stared at him, tears welling in his eyes.

Seiya’s voice became impossibly soft. ”You know exactly who you are.”

Kōya’s lips trembled. ”I...” He couldn’t finish the sentence.

Seiya waited patiently.

Kōya swallowed the knot in his throat. ”Thank you.”

Seiya smiled. Then, he raised his fist slightly from his chest. He pressed it against his heart.

”I love Mizuki.” His eyes remained locked on Kōya. ”And I love you.”

Kōya’s breathing became ragged and unsteady. ”I’ve always loved both of you.”

Seiya smiled in absolute peace. ”With everything I have.”

Kōya stared at him. The words felt strange. Not because they were unfamiliar to him.

But because they were too familiar. Too warm. Something inside his chest hurt with a physical ache, and he didn’t fully understand why.

Seiya slowly lowered his hand to his lap.

Kōya reached across the table, his hand resting near his father’s. ”You should rest now.”

Seiya smiled tiredly. ”Yes.”

”You’ve been fighting.”

”I know.”

”You need to sleep.”

”I think...” Seiya’s eyes began to close. ”...that sounds nice.”

Kōya relaxed slightly, letting out a breath. He thought his father was simply exhausted from the blood loss.

He didn’t understand. He couldn’t see it.

He looked at his son one last time, his eyes barely open. ”I leave Mizuki to you, my son.”

Kōya nodded. ”I will bring her back.”

Seiya smiled. ”I know.”

His fist slowly rose one last time. He pressed it firmly against his heart.

”I love you both.”

Kōya’s eyes filled with tears.

Seiya’s smile remained fixed on his face. ”Stay safe, my son.”

His voice became a ghost of a whisper.

”I will always be watching over you.”