Adding Points to Katsu in Jujutsu Kaisen (Multiverse)

"...So my life is always going to be tied to twisted creatures, huh?" The retired investigator looked at the wildly powerful, utterly obedient twisted cursed energy in his palm, then glanced out the window at a silvery-white twisted thing drifting by. He let out a faint sigh.

[I'm sorry, esteemed investigator, but this is indeed your designated retirement world.] The System's voice was gentle, tinged with guilt.

"...Whatever." Xia Jinliang replied flatly. "After going through so many worlds, there's no going back for me anyway."

Who the hell could go through countless daily life-or-death battles with the Outer Gods, get up close and personal with them, and still have a normal Sanity score and entertain the delusion that a normal life was possible? Whoever could, I'd salute them as a real man.

In fact, this twistedness gave him an indescribable sense of normal, reassuring safety.

[...] The System fell silent.

A new student arrived at Tokyo Jujutsu High. He was handsome, with sharply defined features, yet his East Asian appearance had a refined, scholarly elegance. His manner was lazy and distinctive, but his eyes, usually as brilliant as polished gold, drooped as if tired, hiding the shape and patterns of his irises.

He limped slightly on his left leg and carried a long, slender cane, walking at an unhurried pace.

He was a strange fellow.

That was the consensus among the three classmates who had enrolled a month earlier.

But when Gojo Satoru decided to tease this "weakling" and send him home (he thought weaklings didn't belong in the jujutsu world, where they would die all too easily), he and Geto Suguru, who had rushed in to take the other boy's side, were beaten all over the floor with that long cane. They fled with their heads in their hands, utterly unable to fight back.

The cane wasn't even a cursed tool, just an ordinary walking stick, but when wrapped in the boy's uniquely black cursed energy, it could easily break through Gojo Satoru's Limitless. And whenever the cane struck a certain point, "Blue" would instantly disperse, unable to inflict any meaningful damage.

Of course, monsters could only be conquered by stronger monsters. Before long, the three powerful boys became friends.

It was some time before they discovered that there was nothing wrong with the boy's leg. His left leg simply wouldn't obey him, always dragging backward, completely beyond his control.

At last, after the Six Eyes observed him with the utmost care, they realized that the boy's soul was a radiant gold unlike an ordinary person's, but it was riddled with damage. The part of his soul corresponding to his left leg had vanished entirely, leaving only a strange black force that corroded the area, preventing it from healing and keeping it weak.

...The guy who had beaten them all over the floor was gravely injured, on the brink of death.

They didn't know what Xia Jinliang had been through before coming to Tokyo Jujutsu High, but the two exchanged a glance and decided they had to find a way to mend his damaged soul.

Watching the boy with the man bun grow increasingly radical in his thinking, Xia Jinliang decided he might need to do something.

So he took two little monsters, both lost in their own existence in different ways, and broke into the jujutsu authorities' laboratory to destroy their research. He gathered Sukuna's fingers and used the power of the Old Gods lodged in his damaged soul to erase them forever. He rallied a large number of like-minded jujutsu sorcerers to remake the world, and spent five years cleaning up the entire jujutsu world, even improving the Japanese parliament along the way.

Only after Xia Jinliang showed Geto Suguru so much did he realize that the higher-ups in the jujutsu world, despite possessing cursed techniques and cursed energy, were even more corrupt than ordinary people and caused greater harm to the world.

So his radicalism was cured without hesitation, then nudged a little further, and he naturally set out on the road to a coup.

Five years after the three friends joined forces to reorganize the jujutsu world, defeat a certain thousand-year-old brain, and deal with all of Sukuna's fingers, the world was still rebuilding. One night,

Xia Jinliang looked up at the stars' movements, and his expression darkened.

This world was no longer safe. It seemed to have an Old One of its own.

And it seemed to be waking up.

"...So, of course I can't retire in peace after all." He sighed, looking toward the stars with a grave expression.

The next day.

"Satoru," the young man called to his friend. "I need you to watch me for one minute."

Gojo Satoru was confused, but he did as he was asked and watched him for a minute.

A minute later, Gojo Satoru was sealed inside the Prison Realm.

"You'd never agree to stay safely in the rear, so I had to resort to this." Through the Prison Realm, Gojo Satoru could hear Xia Jinliang, who had deliberately left his hearing intact. He seemed to smile, and yet also sigh. "The Six Eyes are really at a disadvantage against those Old Ones, Satoru."

"So from here on, Suguru and I will take care of things." His voice was gentle and lilting, yet carried an indescribable madness. "If we fail, you don't need to come out either, because by then, destruction will be the world's only remaining path."

"If we succeed, I probably won't survive this investigation." He smiled with the tender gentleness of a spring breeze and drizzle. "Then Suguru and you will have to keep walking the right path."

Then he cut off Gojo's hearing without hesitation.

Premise: Long live friendship