I am Overhaul in Jujutsu Kaisen World

His mother smiled back at him, touched. "Alright. But this is your responsibility now, understood?"

"Promise!" he replied before leaning down to kiss his mother on the cheek. "Thank you, Mom."

He quickly climbed the stairs, the kitten nestled against his chest. When he reached his room, he gently closed the door behind him, smiling at the thought of Sayuri's reaction the next morning.

Ryosuke closed the door to his room and carefully set the kitten down on the floor. The animal shook its head and immediately began to explore the room, its tiny paws pattering on the carpet.

Ryosuke sat down at his desk, arms crossed, observing the little creature with a thoughtful eye.

"Now, you're officially adopted," he murmured with a smirk. "You're lucky my mom has been in a good mood lately."

The kitten stopped abruptly, its ears twitching, before kneeling, its front paws stretched out in front of it as if prostrating itself.

Then, against all odds, a soft yet perfectly clear voice rose in the room.

"My god… thank you for taking me under your protection," the kitten mewed deferentially, its head bowed. "I am eternally grateful for this gift of life."

This was no ordinary cat. It was indeed the one he had "met" during his experiment in the alley. He had pushed his tests beyond what he had initially planned, altering not just the body but also the soul and mind of the cat until it became an animal endowed with human intelligence and capable of speech, among other enhancements.

A cute kitten on the surface, but the reality was darker and more terrible.

The first chimera in a long series to come.

Ryosuke leaned slightly forward, arms crossed, a calm smile on his lips. "Well, well, well. What is your mission?"

The kitten raised its head, its eyes shining with an almost human light. "My mission is to protect your sister, goddess Sayuri, at the peril of my life. Also, I must never speak in public unless you grant me permission."

Ryosuke nodded, satisfied with this answer. "Perfect. Never dare to fail this mission. You have more than enough capability to do so."

"Of course," replied the kitten, bowing its head, its voice vibrating with devotion. "Serving the sister of my god is an honor I will not neglect."

Ryosuke got up from the desk and approached the window, hands in his pockets, his gaze lost in the night's glow.

"My experiments are progressing faster than I expected," he murmured to himself, a hint of satisfaction in his voice. "But this is just the beginning. If I can transform a simple cat into a predator, what's stopping me from going even further?"

The kitten remained still, patiently awaiting further orders. Ryosuke turned to it with a determined look.

"It's time to increase the difficulty."

Ryosuke settled back at his desk. He slid his hand over the mouse and woke up his computer. The screen lit up, revealing his familiar wallpaper: a nighttime scene of a deserted city, illuminated by scattered streetlights.

He glanced quickly at the kitten, now curled up in a corner of the room, silent, its eyes half-closed. He was eager to see his sister's expression upon seeing it. Speaking of which, he also needed to find a "gift" for his mother.

Ryosuke smiled slightly before refocusing on the screen.

He opened his browser and began searching for information about abandoned and eerie places in the area. Abandoned school… abandoned hospital… dilapidated prison… His fingers glided over the keyboard with quiet precision.

He remembered the words from the manga: it was in places like those that the Cursed Spirits lurked.

Initially intending to train quietly on plants and other animals, Ryosuke now felt a newfound confidence within him. He had tasted the power of his ability and knew he was capable of much more. This cat had only been a first step. Now, he had to confront real Cursed Spirits.

He quickly typed "haunted abandoned places Tokyo" into the search bar. Results appeared almost instantly, and he clicked on several of them. Articles about deserted schools, psychiatric hospitals closed for decades, and even cemeteries rumored to harbor wandering spirits flashed before his eyes. But he needed a specific place, one where Cursed Spirits gathered in large numbers, an ideal location to face these cursed creatures and test the true extent of his abilities.

Ryosuke rubbed his chin, deep in thought. Suddenly, he recalled the story of Yuta and Toge. They had faced particularly powerful Cursed Spirits in an abandoned school. But when had that happened in the manga? It had to be in May. He frowned, checking the date on his computer: July. That had already passed.

"Whatever," he murmured to himself.

He continued scrolling through the results. The further he went in his research, the more excitement surged within him. His determination to train in real combat against these creatures was now unshakable.

Ryosuke clicked on a link that caught his attention: an old psychiatric hospital, located an hour's drive from the city. The place was known for its paranormal phenomena, and rumors said no one dared to approach it for years. The idea that powerful Cursed Spirits might reside there was more than likely.

A thin smile crept across his lips.

"Perfect."

He leaned back in his chair, satisfied with his choice. It was decided. He would go there tomorrow morning.

He needed to gain experience, and there was no better way than to immerse himself in a place where Cursed Spirits thrived.

He thought back to his previous experiences with plants, then with the cat. Manipulating living beings felt more natural than he had expected, but he knew that things would be different against Cursed Spirits. Jujutsu battles weren't just about powerful spells; they were also about being prepared mentally, physically, and especially anticipating the opponent's movements.

Ryosuke straightened up, turning off his computer.

"Tomorrow will be a big day."

TO BE CONTINUED!

A/N :

Chapters will now be published every GMT+8 (WN's daily power stone reset time), so fans of this fanfiction will no longer have to lament having finished their power stone and can actively show their support.

Next Chapter: First confrontation