Nothing…
Yaga programs nothing into the cursed corpse he creates with his cursed technique.
This information froze Jin in place, because the implications behind this aspect of Yaga's technique were not good for his future plans.
"Don't lie to me. It's impossible that you make no alterations to the minds of your cursed corpses," Jin declared after digesting the information.
If Yaga wasn't lying, then he would still have the potential to reach Grade S level. However, Jin would not be able to create an army of creatures at his service as easily as he had planned.
He would also have to teach them to obey him.
"Tell me, novice sorcerer… are you familiar with the principle of the incarnation phenomenon?" Yaga suddenly asked.
Jin was confused by the question but nodded.
Incarnation.
It is a rare phenomenon that occurs when an ancient "curse" (a cursed object) acquires a physical body.
Is it a spontaneous phenomenon that cannot be prevented?
The answer is no.
The incarnation phenomenon occurs when a human ingests a cursed object.
After this act of madness, the object—containing cursed energy—can take possession of the body and transform it into a "vessel."
This situation turns the human into a puppet of the object, as the latter seizes their mind and body.
It can even go so far as to alter their appearance to match the one desired by the object.
The "incarnated" state (or junikutai) is described as a fusion between the cursed object and flesh.
"If I remember correctly, the host's body is completely overtaken while their consciousness and ego are annihilated by the cursed object," Jin stated as the image of Yorozu came to his mind.
Cursed objects that have undergone this exotic phenomenon receive memories, knowledge, and the common sense of their vessel's brain.
They also retain the innate technique and all physical aptitudes of their original body, as well as those of the consumer of the cursed object.
The process of transforming a person into a cursed object after death is an esoteric knowledge unknown to the general public in the original work.
Jin's wife had made solemn vows with hundreds of sorcerers over a millennium, binding them to transform their remains into cursed objects.
Those individuals had accepted her invitation because they did not know how to become such objects and desired a second chance.
However, the incarnation phenomenon also has variables.
Yuji Itadori:
He ate one of Sukuna's fingers, thereby incarnating Ryomen Sukuna.
Sukuna and Angel are special cases of incarnation in many respects.
Unlike most cursed objects that have undergone the incarnation phenomenon, Yuji Itadori became a "cage" for Sukuna rather than a true vessel.
As for Hana and Angel, they achieved a symbiotic relationship due to the benevolent nature of the cursed object.
"My cursed technique doesn't truly create artificial cursed corpses, but a kind of incarnated being," Yaga explained after listening to Jin's response to his question.
He shifted his attention away from him and back toward the little cat sleeping after its small seizure.
Yaga picked it up with a gentle motion and held it like a beast in his arms.
"When creating the core of a cursed corpse, the sorcerer injects their cursed energy to program the cursed corpse, but I operate differently," he said, pausing briefly.
Jin wanted to urge him to speak faster but decided against pressuring him.
The man seemed conflicted at that moment, but fortunately, Yaga continued without any prompting.
"I copy the soul's information through the body using my cursed technique, then inject the 'programmed' core into its new host," he finally said.
In other words, Yaga is similar to the curse users who brought Toji back to life in Shibuya.
The only difference is that Yaga does not use a living human to become an "incarnated" being, but a corpse or an object.
"But… what does that have to do with the need to use so many cores?" Jin asked after a slight hesitation.
The deal with Yaga had already been fulfilled, but Jin's curiosity overpowered his rationality.
He wanted to know whether Yaga had used the soul information of his two children on a whim, or whether a sufficient number of compatible soul cores were necessary to create an autonomous artificial soul corpse.
Yaga observed him for a moment before slowly opening his mouth to reply.
"Simply because I want an autonomous cursed corpse," he said, as though Jin had asked a stupid question.
Jin didn't get angry, but he didn't hide the growing confusion on his face.
"I'll try to explain, since it's impossible for you to imitate me anyway."
Yaga gently opened the chest of the cat sleeping in his arms to expose the core of the young cursed corpse to Jin.
"My cores don't contain programming data, but the information of a soul. That's why they can generate cursed energy through strong emotions," he explained, glancing toward Jin.
The former employee displayed an incredulous expression, because Yaga's act was an abomination on an ethical level.
In the Jujutsu Kaisen universe, soul and body are one.
Proof of this lies with Toji and Geto.
One was able to crush his host's soul using only the information from his body.
As for Geto, his body resisted Kenjaku's cursed technique after Gojo's words about him.
To put it simply:
Yaga had literally cloned the souls of his children before implanting them into the body of a cursed corpse (Panda).
Was that the worst part?
No.
For the souls to be compatible, they needed to have a certain connection with one another in order to generate cursed energy.
'Is that why he chose the corpses of a dog and a rat to accompany the cat's core?
All three should instinctively feel repulsion (enmity) toward one another,' Jin thought as he observed Yaga.
These three species do not get along; thus, they will naturally be filled with resentment toward each other.
They will therefore generate their own cursed energy, and since they have been "programmed" using the information of a real soul, the cursed corpse will become autonomous in energy, complete with a genuine personality.
Upon understanding all of this, the former employee displayed a wide smile before turning his back on the future principal of Tokyo Jujutsu High and walking away.
He had received all his answers.
"Wait a moment."
Yaga's voice stopped him.
Jin instinctively emitted cursed energy to counter the injured Grade 1 sorcerer, but the expected attack never came.
A business card was thrown toward him.
"I don't know why you're so obsessed with my cursed technique, but…" Yaga paused before continuing in a compassionate tone.
"I can recognize a grieving person with just one look," he finally said.
A heavy silence settled between them for an indefinite time before Jin ultimately left the place without responding.
Yaga added nothing more.
However, he had not been wrong about his former captor.
Even if Jin refused to acknowledge it,
the face of the real Kaori Itadori haunted him. Otherwise, why would his body react so strongly to Kenjaku?
Another strange element was his choice of the Grade S cursed technique he had decided to copy.
Yuki should normally still be alive at this point in time, and also young and far from her peak in ten years.
Jin could have paid Toji to kidnap her.
Yet he had chosen a Grade S cursed technique focused on time and useless for direct combat.
In the end, he and Jin Itadori were one and the same.
"Kill Buddha… I hope you succeed in lifting the worst curse this world has ever known," Yaga muttered while holding the little cat.
Love.
It is the worst curse of all.
Like Yuta in the future, Yaga had desecrated the corpses and souls of his loved ones.
His act was not motivated by greed… but by a twisted love born from the grief of losing his children.
…
Author's Note:
Here's today's chapter.
Thank you for your support. Even though I started writing this story on a whim, I'm beginning to enjoy developing the protagonist and their relationships with the other characters.