Episode 1: The Night of the Attack

In a quiet, snow-covered town, a boy named Renji and his younger sister Hana live a simple yet harsh life. Their days are filled with struggle, as they barely scrape by in the unforgiving world they were born into. Renji, though still young, has always felt the weight of responsibility, while Hana looks up to him with unwavering trust.

One fateful night, as the cold wind howls through the village, an enormous, grotesque giant emerges from the darkness. Without warning, it rampages through the town, crushing homes and tearing through anything in its path. The ground trembles beneath Renji's feet as he stands frozen in shock, watching in horror as the monster's massive foot rises above him, ready to bring his life to an end.

But in an instant, a shadow moves faster than the eye can see. A powerful warrior—Renji's own father, a renowned Hashira—pushes his son out of harm’s way. The ground shakes violently as the giant’s foot comes crashing down, crushing the warrior beneath its weight. Blood pools beneath the monstrous foot, and Renji's eyes widen as he realizes his father is gone.

Before the children can process the horror, their mother, who possesses some knowledge of demon slaying, steps forward with a determined glare. Armed with only a simple knife, she lunges at the towering creature. With swift and precise movements, she aims for its weak points, but the monster easily overpowers her. It grabs her mid-air, its massive fingers wrapping around her fragile frame. Without hesitation, the creature bites down, severing her head, then cruelly tosses her lifeless body onto the blood-soaked ground.

Renji and Hana are paralyzed with fear, tears streaming down their faces. Just when it seems all hope is lost, the giant suddenly halts, its glowing eyes flickering with recognition. A voice echoes inside its mind, commanding it to return. Without hesitation, the creature obeys, turning away and disappearing into the shadows.

As silence settles over the devastated town, a new figure emerges from the darkness—a Hashira wielding a gleaming blade. His presence is commanding, his movements fluid as water itself. Without a word, he draws his sword and unleashes a breathtaking technique: Water Breathing. In an instant, his blade cuts through the monster with precision, its body falling lifelessly to the ground.

Turning his gaze toward the two trembling children, the Hashira senses something within them—potential. He cannot leave them here, abandoned and alone in a world filled with demons. He makes a decision that will change their fates forever.

“You’re coming with me,” he says, his voice firm but not unkind.

And so, Renji and Hana are taken under his wing, stepping into an unknown future—one filled with pain, training, and the path of a demon slayer.

Episode 2: The Path of the Blade

Renji and Hana arrive at their new home deep within the mountains, where the air is crisp, and the land is untouched by the chaos of the world. Their savior, the Water Hashira, Ryusei, watches them carefully, aware that their lives have changed forever.

“You want revenge?” Ryusei asks as the siblings kneel before him, still shaken from the horrors they witnessed. Renji’s fists clench, and Hana’s eyes burn with determination.

“Then you must become strong. You must learn the way of the blade.”

Training Begins

From that day forward, their grueling training begins. Ryusei hands them wooden swords, their weight unfamiliar in the children's small hands.

“You will swing these every day until your arms can no longer move,” Ryusei instructs. “A real sword is not something you can wield without proper strength and control.”

For hours, Renji and Hana swing their wooden blades under the blazing sun. One thousand strikes in the morning. One thousand at noon. One thousand at dusk. Their bodies ache, their fingers blister, but they push forward, refusing to stop.

At night, Ryusei gathers them near a bonfire. His blue eyes are sharp as he begins their lessons on the world they have entered.

The Truth About Demons

“Demons are not simply mindless monsters,” he explains. “They were once human. They were turned by an ancient evil—one that continues to spread its curse.”

Renji listens intently, his grip on his wooden sword tightening.

“Demons do not die from normal wounds. They regenerate. The only way to kill them is by decapitation with a Nichirin Blade or exposing them to the sun. They are stronger than humans, faster, and relentless. You cannot hesitate when you face one.”

Hana, despite her exhaustion, nods firmly. “Then we must become faster and stronger.”

Ryusei smirks slightly. “Exactly.”

Mastering Water Breathing

The next day, Ryusei demonstrates the forms of Water Breathing, each strike flowing like a river, each movement a dance of death.

First Form: Water Surface Slash – A single, powerful cut that can slice through a demon in one motion.

Second Form: Water Wheel – A spinning attack, perfect for enemies above or below.

Third Form: Flowing Dance – A series of graceful, continuous strikes, overwhelming an opponent.

Fourth Form: Striking Tide – A rapid series of slashes, like crashing waves.

Fifth Form: Blessed Rain After the Drought – A merciful, painless execution.

Renji and Hana are mesmerized, their eyes reflecting the sharp gleam of Ryusei’s blade.

“Before you can master these techniques, you must first learn control,” Ryusei tells them, handing them their wooden swords again. “Balance. Strength. Endurance. These are what will keep you alive.”

A Mother’s Kindness

After brutal training sessions, the siblings return to Ryusei’s home, their bodies sore and spirits drained. Waiting for them is Kaede, Ryusei’s wife, a former demon slayer. Though her days of battle are over, her heart remains as strong as ever.

She greets them with a warm smile and places bowls of steaming rice and miso soup in front of them. “Eat,” she insists, gently patting Hana’s head. “You won’t grow stronger if you collapse from hunger.”

Renji hesitates, unaccustomed to kindness after losing his parents. But the moment he tastes the food, warmth fills his chest. Hana, sitting beside him, beams.

Kaede watches over them as they eat, treating them as if they were her own children. “Ryusei can be strict, but he cares for you. He wouldn’t have brought you here otherwise.”

For the first time in a long while, Renji and Hana feel something they thought was lost—a sense of home.

The Journey Ahead

As days turn to weeks, their training intensifies. Every morning, they train with their wooden swords. Every night, they learn about demons. The siblings endure, pushing past their limits, determined to become strong enough to never lose anyone again.

And so, their journey as Demon Slayers in training truly begins.

Episode 3: The First Kill

Four years have passed since Renji and Hana began their grueling training under Ryusei, the Water Hashira. The siblings have grown stronger, their bodies hardened through relentless practice. Every day, they wake before sunrise, training until their muscles burn and their lungs beg for rest.

Renji, now a teenager, swings his blade with force, but something still feels off. No matter how hard he tries, he cannot unleash Water Breathing. Hana, on the other hand, moves with grace, her form nearly perfect.

One night, as they sit outside under the cold moonlight, Renji clenches his fists, frustration clear on his face.

“Damn it,” he mutters. “Why the hell can’t I use Water Breathing? I’ve trained every single day, just like you, Hana.”

His sister, now 12, looks at him with soft eyes. “Maybe you’re trying too hard,” she suggests. “Ryusei always says breathing should feel natural, like a flowing river.”

Renji scoffs. “Easy for you to say. You make it look effortless.”

Hana sighs. “You’ll get it, Renji. I know you will.”

A Demon Strikes

That night, as the siblings sleep, a chilling wind rushes through the house. The scent of rotting flesh fills the air, followed by the sound of footsteps approaching their room.

Renji’s eyes snap open. He hears the floor creak, and his heartbeat quickens. He slowly reaches for his wooden sword.

Then—BANG!

The door explodes into splinters as a demon lunges toward them, its blood-red eyes gleaming in the darkness. Its claws slash forward, aiming for Hana’s throat.

Renji acts on instinct, shoving his sister behind him as he swings his sword. But the demon easily blocks the attack, grinning with sharp, jagged teeth.

Ryusei appears in the doorway, but he does not move. His arms remain crossed, his face unreadable.

"Fight," he commands. "Show me what you’ve learned."

Renji’s hands tighten around his blade. This is it. This is the moment he’s been training for. He takes a deep breath, preparing to unleash Water Breathing—

Nothing happens.

His body remains stiff. His lungs feel heavy. The technique won’t activate.

“Shit! Why the hell can’t I use Water Breathing?!” he shouts, sweat dripping down his face.

The demon lunges again, and Renji barely dodges. His movements are too slow, too forced. He knows he’s going to lose.

Then—a flash of blue.

Out of nowhere, Hana moves forward, her blade shimmering under the moonlight. She takes a deep breath, her posture perfect. The world around her slows as she focuses.

“Water Breathing, First Form—Water Surface Slash!”

Her sword cuts cleanly through the demon’s neck. For a brief moment, time seems frozen. The demon’s head flies through the air, landing with a dull thud. Its body collapses right after, turning to ash before their eyes.

Renji watches in stunned silence, his wooden sword still clenched in his hands. He turns to his sister, who is breathing heavily, her hands shaking.

She did it.

She just killed a demon.

Aftermath

Ryusei steps forward, nodding in approval. “Four years,” he mutters. “And tonight, Hana has slain her first demon.”

Hana looks down at her hands, still trembling. “I… I did it?”

Ryusei places a hand on her shoulder. “Yes. And you did well.”

Renji, however, remains silent, his emotions tangled between pride and frustration. He trained just as hard—maybe even harder—but when it mattered, he failed.

Hana sees the look on his face. “Renji…”

He forces a smile. “You were amazing, Hana.”

But deep down, his frustration burns.

Episode 4: The Breaking Point

The warm glow of lanterns flickered inside the house as Renji, Hana, Ryusei, and his wife Satomi gathered for dinner. The scent of grilled fish, rice, and miso soup filled the air. The meal was simple yet comforting after another grueling day of training.

Renji sat quietly, poking at his food. His mind was clouded, frustration eating away at him. Hana, on the other hand, ate happily, still glowing from her first demon kill.

Ryusei took a sip of tea before turning his sharp eyes toward Renji. Then, with a smirk, he spoke.

"Four years of training, and you still can't use Water Breathing? Pathetic. You're a disgrace to me... and your dead family."

Silence filled the room. Hana’s chopsticks froze mid-air. Satomi’s face darkened, her eyes narrowing at her husband.

Renji’s fingers tightened around his bowl, his teeth gritted. His breath quickened. He had endured Ryusei’s harsh training, his brutal words—but this?

This was too much.

He slammed his fists onto the table, knocking over his bowl. “Maybe I don’t need you, old bastard!” he shouted, standing up.

Satomi gasped. Hana’s eyes widened in shock.

Ryusei chuckled darkly. “Is that so? Then go ahead. Leave.”

Renji turned toward the door, fists clenched. His rage boiled over. He had nothing to prove to this man.

As he reached the door, Ryusei’s voice cut through the air like a blade.

“You bastard. It’s the Third Great Demon War. Demons roam the streets like wild animals, slaughtering innocents. The Hashira and demon slayers are fighting endlessly, trying to hold them back. If you leave now, you’re as good as dead.”

Renji paused. His breath was ragged. But he refused to look back.

“I don’t goddamn care.”

And with that, he stepped into the darkness, slamming the door behind him.

A Reckless Choice

The night was cold, the streets eerily silent. Renji pulled his cloak tighter around himself as he walked through the desolate road.

Then—he heard it.

A low growl. A shadow shifting in the darkness.

His blood ran cold.

A demon.

Emerging from the shadows, a monstrous creature grinned at him, its fangs glistening under the moonlight.

Renji’s heart pounded. He stumbled backward, his voice shaking.

“Shit... shit!”

The demon lunged.

Renji turned and ran.

His feet pounded against the dirt road as he sprinted through the empty streets. The demon’s snarls grew closer.

"Get away from me, you bastard!" Renji shouted, sweat dripping down his face.

The demon was faster. Too fast.

Just as it was about to sink its claws into him—

SHING!

A blade flashed through the air, slicing cleanly through the demon’s neck. Blood sprayed. The creature let out a gurgled scream before crumbling into ash.

Renji fell to the ground, gasping for breath. His eyes darted up—

Hana.

She stood over him, her sword dripping with demon blood, her expression calm yet sad.

She sheathed her blade and looked down at him. “This is my last gift to you,” she whispered. “I hope you become stronger, Renji… until we meet again.”

Renji stared at her, his mind racing. “Hana…?”

But she had already turned away, disappearing into the night.

Alone in the Darkness

Renji wandered, his feet heavy, his mind numb. His body ached, his pride shattered.

Eventually, he found shelter in a dark cave, near an old water well.

He sat against the cold stone wall, wrapping his arms around his knees.

Alone. Weak. Lost.

As the wind howled outside, Renji closed his eyes.

Tomorrow… he would have to find his own path.