The walk back was the happiest Hayato had ever been. He imagined his father's eyes widening at the Blue Spider Lilies and his mother's laugh as she tucked one behind her ear. He was fifteen, the strongest sorcerer in the Kurogane line, and he felt as though the world was finally rewarding the kindness he had tried so hard to cultivate.
But the mountain air changed. The scent of pine was swallowed by a thick, metallic stench—the smell of a slaughterhouse.
Hayato's basket hit the dirt. The priceless blue petals scattered, unheeded, as he sprinted toward the estate. "Father! Mother! Ren!"
He burst through the gate, and the world broke. The courtyard, once filled with the rhythmic clack of practice swords, was a sea of red. His cousins, his aunts, his uncles—everyone who had given him the warmth he lacked in his past life—lay still. He found his father near the porch, his hands mangled as if he had fought a beast with his bare palms. In the shadowed hallway, he saw his mother, Shizuku, her body draped protectively over the youngest children. Her Hanafuda earrings glinted one last time in the fading light.
"Damn sorcerers..."
A wet, rasping voice pulled Hayato's gaze to the corner of the porch. A figure sat there, clutching a shredded stomach. He looked like a man, but his skin was a sickly, pale grey, and his eyes were a piercing, unnatural yellow with slit pupils.
"It took my entire gang to bring this place down," the creature hissed, a jagged grin spreading across his face. "Even I am severely wounded. Your people... they fought like cornered rats."
Hayato's breath hitched in a sob of pure terror. "Who... what are you?"
With a sudden, blurring speed, the creature lunged. He pinned Hayato to the wooden floor, his claws digging into the boy's shoulders like hot iron.
"I am a Demon," the monster whispered, his breath smelling of rot. "And we came for a hunt. Sadly, your 'damned sorcerers' took the entire mob with them. I'm the only one left standing to enjoy the leftovers."
"Why?" Hayato screamed, his tears blurring his vision as he looked at his mother's still form. "How could you do this to innocent people? If you were hungry... there are deer in the woods! Birds! Why my family?"
The demon threw his head back and laughed, a mocking, screeching sound that echoed through the silent house. "Animals? You think we are mere beasts? Humans are cattle, boy. You are weak, delicious, and exist only to be consumed. Your 'goodness' is just seasoning for the meat."
As the demon spat on the memory of his kin, the grief in Hayato's heart began to curdle. He looked at the creature—a thing that murdered children for sport and mocked the very concept of life. This wasn't a predator following the laws of nature; it was a monstrosity. A mistake. A parasite that had no right to exist in the same world as the people he loved.
******
The demon's laughter died in its throat as a sudden, unnatural heat began to radiate from the boy beneath its claws.
The creature was a Lower Moon, a title that marked him as one of the elite among Muzan's ranks. To him, this child was nothing more than a stray sorcerer, a weakling who had missed the slaughter. But he was mistaken. Hayato was not just a child; he was the prodigy of the Kurogane line, and his grief had just struck a match against his soul.
"Burn," Hayato whispered, his voice cracking.
With a roar that shook the very foundations of the estate, a massive pillar of crimson fire erupted from Hayato's body. The demon shrieked, leaping back as his flesh began to blister and melt. Panicked, the creature finally realized the danger. He could sense a power coming from this boy that far surpassed the elders he had killed earlier—a raw, terrifying mastery of the flame.
The Lower Moon tried to fight back, lashing out with a Blood Demon Art of jagged shadows, but it was a one-sided slaughter. Hayato didn't just strike; he incinerated. Every ounce of his training in the Lesser Magic was poured into a single, focused intent: Destruction. Within moments, the demon was nothing but a pile of white ash scattering in the mountain wind.
As the silence returned, Hayato stumbled through the ruins of his home. He looked at the scorched earth and the sheer number of footprints. He realized then that his family hadn't been weak—they had been overwhelmed. A massive horde of demons had descended on them, and though his kin had taken dozens of the monsters with them to the grave, they had simply been outnumbered.
Hayato collapsed to his knees among the bodies of his parents. He tried to act strong, the way his father had taught him. With trembling hands and a hollow heart, he spent the next few days digging. He buried his father, his mother, and every one of his cousins, marking each grave with a simple stone.
For one month, Hayato tried to live a normal life. He stayed in the house, gathered herbs, and ate the simple meals his mother had taught him to make. He tried to be the kind, cheerful boy they had loved. But as the weeks passed, the weight of the silence became unbearable. Every corner of the house reminded him of a laugh that was gone; every sunrise reminded him of the mother who would never dance the Kagura again.
He realized that everything worth living for—the warmth, the smiles, the very heart of his world—had been stolen. In the span of thirty days, his grief curdled into a black, poisoned hatred. The normal life he desperately wanted to preserve had become a hollow shell.
Standing before the graves of his family, Hayato made a final, jagged vow. "I will kill them," he rasped, his eyes cold and devoid of the light they once held. "Every single one of them. I will hunt the monsters who took everything, and I will leave nothing but ash."