Michikatsu sat awake in his room, the memories of the last five years haunting him. Ever since his position with Yoriichi had been usurped, resentment burned within him. The room was sparse, devoid of any luxury, a single mattress on the floor, stripped of privileges once his. His sword was the only thing that remained, a silent testament to what he could no longer become. He wasn't allowed to join the Demon Slayers. Rising to leave for his secret nightly training, he froze at the sound of a voice outside.
"Brother?" called the familiar voice. Yoriichi. What is he doing here?
"What?" Michikatsu answered, his tone sharp.
"Mother has passed."
Shock froze Michikatsu in place. How could that be? She had been frail but seemed to be improving not long ago. Rising swiftly, he strode to the door.
"What did you say?" His confusion turned to frustration. "What happened? How could you just say something like that so casually?"
Opening the door, he met Yoriichi's steady gaze, but he couldn't understand the calm sadness in his brother's eyes.
"Forgive me," Yoriichi said, bowing slightly. "I beg that you hear me out. As the heir to our family, you have a duty to uphold. Tonight, I will leave home and let you be heir."
"You're leaving now?" Michikatsu blurted, unable to process the sudden announcement.
"Yes," Yoriichi replied. "But before I go, I wanted to bid you farewell. This flute-"
"A flute?" Michikatsu interrupted, baffled, but Yoriichi continued.
"I will strive, day after day. No matter how far I drift, I will not lose heart, for I will think of my elder brother, who gave me this flute."
Yoriichi held the seemingly useless flute with reverence, wrapping it in cloth as though it were a treasure. Michikatsu couldn't comprehend how something so insignificant could bring his brother such joy.
"Farewell," Yoriichi said, bowing once more before leaving with nothing but the flute.
Michikatsu stood frozen in the doorway, his emotions a storm of confusion, anger, and disbelief. Shaking himself from the haze, he turned toward their mother's room, determined to understand.
Entering the room, he searched frantically for answers. His eyes landed on a diary—perhaps this would reveal the truth. Just then, a sound broke the silence.
"What was that?" he muttered aloud.
A scream pierced the air, raw and guttural.
"Father!" he exclaimed, sprinting back to his room. He grabbed his sword and donned his black-and-purple checkered haori before racing toward the source of the noise.
As he neared, Michikatsu slowed his steps, his breathing steadying as he drew his Nichirin blade. Pushing open the shoji door, he was met with a scene of horror—blood painted the walls, bodies littered the floor. His stomach churned.
In the center of the carnage stood a man. Clad in a black suit and white pants, he was impossibly handsome, yet the blood that stained him made his demonic nature clear.
The man turned, his crimson, slitted eyes locking onto Michikatsu.
"Oh," he said with a cold smirk. "You're not who I'm looking for. But since you're here… entertain me."
Michikatsu readied his stance. "Moon Breathing, Second Form: Pearl Flower Moon Gazing"
Three crescent-shaped slashes cut through the air, but the demon blocked them effortlessly with his hands. He countered with a casual swipe, and Michikatsu leaped back, narrowly avoiding the strike. This is no ordinary foe.
"Why are you running, boy?" the demon taunted, his voice dripping with mockery. "Fight me."
Michikatsu gritted his teeth and launched into another attack. "Third Form: Loathsome Moon, Chains"
Two wide, arcing slashes followed, but the demon walked through them unscathed, his regeneration too fast. He lunged, his clawed hand slashing across Michikatsu's stomach. Pain erupted as he was sent flying, his vision blurring.
Even as he screamed in agony, Michikatsu forced himself to stand. He couldn't lose here, not like this. Summoning his strength, he charged forward.
"Sixth Form: Perpetual Night, Lonely Moon, Incessant"
A wild barrage of crescent moon blades filled the air, slicing through the surroundings. The attack struck the demon, drawing blood and eliciting a flicker of rage in his expression.
"Impressive, boy," the demon growled, his voice low and dangerous. "But now, you die."
As the demon raised his arm, Michikatsu felt a searing heat ignite within him. His forehead and jaw burned, his heart pounded furiously.
I am Michikatsu Tsugikuni. I was born to die, but not before I surpass them all.
"The Curse Mark, petulant worm you may be, but you are impressive perhaps you may still be of use." He rushes in with murderous intent. Michikatsu stood, sheathing his sword, "Moon Breathing First Form: Dark Moon, Evening Palace", drawing his Katana he performed a singular horizontal slash following a crescent shape, creating numerous chaotic crescent blades along its path. The power of this 'curse mark' felt enormous. he would never have been able to do such attacks at his age. The Demon weaves the attack elegantly and Michikatsu attacks. Second Form: Pearl Flower Moongazing, this time he performed three crescent-shaped slashes while releasing a multitude of crescent moon blades along with them.
"Blood Demon Art: Black Blood Brambles," the demon intoned, his voice filled with malice.
A web of thorny tendrils erupted from the demons arms, entangling Michikatsu. Blood sprayed as the tendrils cut deep, and the demon advanced.
"I could not find the other one," he said, his tone almost contemplative. "But you… you may still serve a purpose."
Michikatsu's vision blurred as the demon plunged his arm into his mutilated shoulder. A sickening energy coursed through him, and his body convulsed. The demon's voice echoed in his fading consciousness.
"I dub you Kokushibo. Let us see if my experiment bears fruit."

I updated it since it was hot garbage before, I still think it's garbage I might come back, but atleast it isn't hot garbage. Anyways I hope this is an improvement and yes it is still short.