I decided to rewrite my story as I felt it was too immature. I have taken your reviews into account and I encourage you to continue to do so, as it helps me learn to be a better author. Some of the story changes quite a fair bit from the Original fic but I like this version better.

I do not own My Hero Academia or Demon Slayer, this is a work of my imagination based on the 2 series.

Chapter 1: A Dark Fate

Flashback, 14 years ago:

"Doctor, what quirks do my children have?" asked Inko Midoriya, a fit, green-haired woman who appeared to be in her early thirties.

The doctor, an older man with glasses, looked down at his clipboard with a calm expression. "Well, Mrs. Midoriya, I have both good and bad news. Which would you like to hear first?"

The four-year-old girl sitting beside her mother bounced excitedly in her seat. "Me! Me! Me!" she exclaimed.

Izuku, her twin brother, smiled softly and gave her a nod, allowing her to go first.

The doctor chuckled. "Very well, young lady. You're in for some exciting news." He adjusted his glasses and turned to Izura. "Your quirk is Air Manipulation. This ability allows you to control air currents and use them however you see fit. You could create weapons, armor, or even incapacitate someone by manipulating the air around them."

Izura's face lit up with a bright grin. "Yay! That sounds amazing!" she cheered, twirling around in excitement.

"You could be an incredible hero with that quirk!" Izuku added, his face glowing with admiration. "You could do so much with it!"

Izura puffed out her chest proudly. "I'm totally going to be the Number One Hero with these powers!"

Izuku, unable to contain his excitement, immediately turned to the doctor. "What about me? What's my quirk?"

The doctor's expression shifted slightly, a subtle hint of concern clouding his features. He cleared his throat before answering. "Well, young man, your quirk is... Demon."

Inko's eyes widened at the ominous name.

The doctor went on, "It grants you six eyes, immense physical strength, and enhanced speed. You will also be able to summon a demonic sword that can slice through almost anything."

Izuku, unaware of the gravity of his quirk's implications, raised his fists triumphantly. "Yoasha! I'm going to be the Number One Hero, too!" he declared, his eyes sparkling with unbridled optimism.

Inko's hand clenched around her son's, her knuckles turning white. Her heart began to race as she processed what the doctor had said. Demon... She couldn't help but feel a pang of fear. That sounds like a villain's quirk.

Izuku, oblivious to his mother's worry, looked down at her with a smile. "I'll be okay, right, Mom?"

Inko forced a smile, but her anxiety was evident. "Of course, Izuku..."

The doctor's voice broke through her thoughts. "It is a powerful quirk, no doubt. But, as with all things, it requires control. I would advise you to be cautious."

Izuku nodded enthusiastically. "I'll work hard to control it!"

Inko, trying to mask her unease, gave a curt nod. "Thank you, doctor. Let's go, kids."

As they left the clinic, Inko's grip on Izuku's hand tightened. The tension in her fingers was almost painful. "Ow, Mom, you're hurting me," Izuku complained, looking up at her.

Inko snapped, her voice sharp. "Quiet, Izuku."

Izuku flinched, his expression faltering. This was the first time he had seen his mother react like that. He fell silent, feeling a heavy weight settle in his chest.

Later that afternoon, Inko drove the twins to a nearby park. "Alright, go play with your friends. We'll be here for a little while," she said, forcing a cheerful tone as she smiled at them.

Izura and Izuku ran toward the group of children waiting for them by the swings, all of them excited to share their new quirks.

"Hey, guys! What quirks did you get?" Izura asked as she joined her friends.

Katsuki Bakugou, with his usual fiery energy, grinned. "I got Explosion! You know, the usual—BOOM!"

Shoka Todoroki, Shoto's twin sister, added, "I got Half-Cold, Half-Hot! Just like Shoto, but with my own twist."

Shoto, in his usual calm and measured tone, spoke up next. "My quirk is Half-Hot, Half-Cold. It allows me to control both fire and ice."

Izura beamed proudly. "I got two quirks! Air Manipulation and Total Body Enhancement! I'm going to be the best hero ever!"

Izuku, his heart pounding in his chest, turned to his friends. "So... what about me?"

Katsuki squinted at him, a smirk curling up at the corner of his lips. "What'd you get, Deku? A villainous quirk?"

Izuku blinked, confused. "What do you mean?"

"Demon, huh? Sounds like a villain's quirk to me," Katsuki said with a sneer, his explosive energy flaring up just slightly as he spoke.

The others stared at Izuku for a long moment, unease slowly creeping into their expressions. Shoka's voice trembled slightly as she spoke. "That sounds... dangerous."

Shoto, usually composed, nodded in agreement. "You'll be... the enemy."

Izura's expression faltered for the first time. She opened her mouth to speak but closed it again, unsure of what to say. The silence that followed was thick with tension.

Katsuki laughed, his voice bitter. "The hero's job is to stop villains, right? And you—" He paused, eyes narrowing as he took a step back. "You're gonna be one."

Izuku stood frozen, his face pale as the realization hit him. The other children began to back away, their fear palpable. They activated their quirks, and with a few bursts of flames and explosions, they began to push him away.

"Stop!" Izuku shouted, his voice trembling. "I'm not a villain!"

Flashback ends

But the words were lost in the noise as his childhood friends—people he had grown up with—turned on him. The laughter in their voices echoed in his ears as they used their powers to mock him. It was all too much. For the first time in his life, he felt completely alone.

At home, things were no better. His mother barely acknowledged him as she doted on Izura, who was excelling in every way. Inko's attention was consumed by her daughter's promising future. The love that Izuku had once felt was now distant, as cold and empty as the home they shared.

When Izuku turned twelve, things only grew worse. Hisashi Midoriya, his father, a well-known hero, came and went, his presence more like a shadow than a parent. His real identity, Salamander, the No. 2 hero, didn't help the situation. And Inko, now Magna, the No. 8 hero, was no better. They were too busy with their careers to care for their son.

Izuku's only companion was his own despair.

It wasn't long before Izuku made the painful decision to leave. His heart shattered, but he couldn't stand the neglect any longer. One quiet night, he wrote a brief letter, packed what little he had, and slipped away into the darkness.

As he ran through the streets, using his quirk to boost himself, he suddenly felt a sharp, cold sensation. His quirk... It was gone. Izuku faltered, confusion and fear spreading through him like wildfire. He spun around to find a man standing in his path.

The man's eyes glowed a menacing red. "Hey, kid. You're not supposed to use your quirk outside."

Izuku blinked, shocked by the stranger's appearance. His voice shook as he apologized, "I'm sorry, sir. I won't do it again."

The man, Eraserhead, studied him with a look of quiet concern. His eyes flicked to Izuku's scarred arms, then back to his hollow gaze. "You haven't eaten, have you?"

Izuku hesitated but nodded weakly. His stomach growled loudly in protest.

Eraserhead, with a sigh, motioned for Izuku to follow. "Come on, kid. You need food. Let's get you something."

Izuku, too exhausted to argue, followed the strange man in silence, wondering where this new path would lead him.