Into the Hunter x Hunter world with Jujutsu Kaisen System

(Author's note: Sachiko's already pretty OP but let's make her even more OP cuz why not? xD

Just to clarify though, Sachiko's talent in Nen has nothing to do with System. She just has better talent in Nen than cursed energy, which is actually ironic, seeing she has a whole system based on Jjk power system.

I don't know much about aura pool because I haven't reached those parts of the manga yet and I based this on discussions found on reddit so correct me if I'm wrong . I'm also pretty bad at Math so calculating numbers and such made me lose so much braincells. but hey, I tried my best.)

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Sachiko continued to train for four more days as she told Killua and Gon to train five more days the day before going to Heavens Arena. During those four days, Sachiko diligently trained her 'Ten' and 'Ren' and meditated while she was not training either of them. She also trained her sword skills while she trained to maintain 'Ten'.

As a result, she could now maintain 'Ren' which could be called 'Ken' if maintained for a long time by combining it with 'Ten' continuously for twelve hours and 'Ten' for as long as she stayed awake. She had not mastered it to the point of being able to maintain it even in her sleep but as long as she was awake, she could now maintain her 'Ten'.

As she could use 'Ren' more naturally now, focusing it on her eyes to use 'Gyo' became much easier as well.

With such progress, she had finally decided to do Water Divination test to find out her nen type. According to Hisoka's analysis, she should be a Transmuter or a Manipulator but with the system reward, she had a feeling that it might not be as simple.

Anyway, Sachiko made preparations for Water Divination. She filled a glass with water and then put a leaf on the surface of the water.

Taking a deep breath, Sachiko started to use 'Ren' but focused the aura around her hands as she put her hands on each side of the glass.

As she poured her aura in, changes started to happen.

The leaf floating at the middle started to move and swirl around.

Sachiko subconsciously tasted the water despite knowing the leaf moved earlier, meaning she was a manipulator.

To her surprise, the water was slightly sweet!

Meaning she also was a Transmuter.

"Wait, can someone be a Transmuter and Manipulator at the same time? That's like two different categories.." Sachiko voiced out her doubts.

This time, System replied to her.

[Host's initial types are indeed Transmuter and Manipulator. To be precise, since host has technically lived two lives with the same conscious soul, some traits and energies from your previous life are carried over, then host developed a new set of views in a new world, allowing you to develop complete compatibility for another suitable nen type.]

'You make it sound easy and simple but it isn't that easy, is it?'

[People can rarely go to after life with their memories intact or even their souls intact and without getting changed a single bit. However, host had different conditions and directly transported to this world with a new body, allowing your soul and memories to be completely intact. That said, host's nature had changed a bit since you've got to this world and as a result of such change, host had become compatible with another nen type, Manipulation. Since the core of your soul never changed, System made sure to keep your compatibility with Transmuter and this led to having complete compatibility with both types.]

"Oh..wow.." Sachiko found the turn of events hard to believe. She had never expected to have two nen types. Not that she hated it but she was finding it hard to contain her excitement.

After calming herself down a bit, she remembered one of System rewards, Nen Category Compatibility.

'System, what is Nen Category Compatibility? I didn't notice anything else when I did Water Divination earlier.'

[Nen Category Compatibility is a passive ability that will allow host to master other categories up to 100% as long as host believes they can compliment your main categories.]

'So, in other words, I won't need to worry about the category crossing issue.'

[However, host will find your main categories easier to learn. While you can achieve 100% mastery over other categories, time and effort taken to learn may be more than learning your main categories. That said, host will not have any problems matching the masters other category types once you've learned since you have 100% mastery over it.]

In other words, only learning part will be a bit harder and once she got past the learning stage, she could utilize the true power of any category. She wouldn't face the same problem category crossers had to face.

If she remembered well, Kastro lost to Hisoka because he tried to master conjuring despite being an enhancer. As a result, his enhancement and nen abilities suffered while he could only master 60% of conjuring and when he put more painstaking efforts in conjuring a clone, his talent in nen was squandered.

But, for Sachiko, she could try to learn other categories such as emission, enhancement and conjuring without her performance having to suffer. Surely, she would take more time and effort to learn those categories but that was about it. She didn't truly have to worry about squandering all her talent in the wrong category because she could use all categories up to 100% as long as they can compliment her main categories.

Besides, her talent in Nen seemed to be that of a genius so consuming a bit more time to learn other categories will not necessarily make her fall behind as long as she didn't overdo it.

With that information, Sachiko was at ease, thinking about her future moves. Since she didn't have to limit herself much, the possibilities were endless.

She could take time to taylor her special moves that suited her.

So, Sachiko wasn't in a rush to develop a Hatsu for her abilities yet. She would take time as she would with her other categories.

At least, now that she knew what her main categories are, she could take time to think about it.

With that in her mind, she put away the water glass and prepared to teach Killua and Gon 'Nen'. As usual, she used 'Ten' before stepping out of the room. It had been a routine that whenever she wasn't training other Nen techniques, she always used 'Ten'.

Stepping out of the room and going downstairs, she saw Killua and Gon training.

"Hey, how's it going?" Sachiko asked, waving to the two kids.

"I'm a bit tired but I think I'm getting stronger!" Gon answered in a cheerful voice.

"Good, Killua?"

"Not too bad, I guess" Killua replied.

"Great! Although I wanted to test out your physical strength, I guess that'll have to wait." Sachiko muttered.

"Can I spar with you? I want to know how much I've got stronger!" Gon asked.

Killua was surprised and yelled, "Oi, didn't you remember about her being a Nen user part?"

"He's right, Gon. If you fight with a nen user without knowing Nen, you can end up crippled just by them using Nen." Sachiko said.

"But, you won't hurt me, right? We've fought during Hunter Exam as well and you didn't injure me that badly." Gon said in his awfully optimistic manner and Sachiko groaned.

"Fine, get out of that training suit and rest for a while. I'll spar with you half an hour later." She said.

Gon cheered as if he won the lottery.

'Just what's wrong with him? Or more like what isn't wrong with him at this point?' Sachiko thought to herself.

During thirty minutes, Sachiko opened System Store to see if she could buy anything else from the store to go with her Nen abilities. But, she was caught off-guard by the changes in the store.

[System Store

Hunter (Hunter points)

Enhanced sense : Superior sense of smell (100 points)

Enhanced sense : Absolute sense of taste (100 points)

Enhanced sense : Absolute sense of touch (100 points)

Physical Enhancement: 10 times Enhancement of all physical abilities. (300 points)

Enhanced Reflexes (100 points).

Enhanced Aura Refill : Increase the production or refill of aura by TWO times and THREE times during Zetsu. (3000 points)]

'Aura refill?' Sachiko wasn't expecting this. Wouldn't she be able to train more if her aura restored faster?

But the amount of points required made her shake her head.

Just how long would she need to wait to save up 3000 points?

Now, she only had 120 points so she would need to save up another 2880 points.

As it'd take a long time, Sachiko decided to go with Enhanced Reflexes first.

If she truly wanted to fight serious battles, she would need good reflexes as well. Just relying on pure strength and power couldn't get her to the maximum potential.

'System, I'll buy Enhanced Reflexes.'

[Enhanced Reflexes bought successfully. Remaining hunter points: 20.]

'Great, I'll test it out in the spar later.' Sachiko thought before focusing on training her cursed energy manipulation technique as it had been a while since she had focused on it.

To her surprise, she successfully levelled up to Proficient.

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Sachiko chan's update stats

Name : Nakamura Sachiko

Alias : None.

Age : 19

Relationships : Gon Freecs (Close Friend), Killua Zoldyck (Adopted brother), Kurapika (Friend), Leorio Paradinight (Friend), Hisoka (Rivals), Illumi (Enemy), Geto Suguru (Enemy), Gojo Satoru (Acquaintance ), Wing (Acquaintance).

Assets : 225 million yen, 800 million jenny house, 100,050,000 jenny.

Hunter level : C

Jujutsu sorcerer level : Grade-1

Cursed technique : Cursed energy manipulation (Proficient), Time Manipulation Eyes (Advanced beginner), Nullify (Novice), Pain killer (Competent), Reverse Cursed Technique (Advanced Beginner).

Cursed energy : 9400/10,000

Cursed energy reserves rank : C

Nen Techniques: Ten (Proficient), Ren/Ken (Competent), Zetsu (Proficient), Gyo (Competent).

Nen Abilities: None.

Nen Type: Manipulator, Transmuter.

Aura pool: 78,000 units

Curse points : 280.

Hunter points : 20.

Cursed tools : Special Grade Scythe.

Skills : Intermediate Sword Skill (Competent), Assassins Art: Shroud (Competent), Assassins Art : Silent gaits, Rhythm Echo (Competent), Disguise (Novice).

Abilities : Enhanced sense : Eyesight , Super Hearing, Superior Strength (20x), Enhanced Reflexes.

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