Transmigrated Become Sukuna, but the host is Yukinoshita Yukino?

"Ah~"

Hikigaya Hachiman lay in the bathtub and let out a groan without thinking.

The hot water soaked his body, and all the pores on his skin opened up, releasing the tiredness of the day.

Even Komachi, who was studying in the living room, heard his voice and said with some surprise, "Oh, it's rare to hear you make a sound like that, brother. You must have had a long day at work."

"Don't worry about it," Hikigaya Hachiman mumbled, covering his face with a hot towel.

He didn't have work, but he was really tired, not just physically but also mentally.

'Think more about the essence of curse energy, and you'll understand why you failed earlier.'

Recalling what Hayashizaki had said, the relaxed Hikigaya Hachiman began to think.

The essence of curse energy is energy born from human negative emotions. Did I succeed the first time because I was filled with negative emotions?

Do I have to stay in a state of anger and fear to use curse energy?

Hikigaya Hachiman immediately dismissed this thought.

Just look at Hayashizaki. When he demonstrated the difference between a simple curse energy attack and using a technique, he didn't seem to have any negative emotions. He even looked like he was enjoying it.

Do I have to be like a professional actor, able to cry on command, and think of sad things to generate curse energy?

If that's the case, I have plenty of sad memories!

Hikigaya Hachiman pulled the towel off his face and immersed himself in his buried, painful memories...

I can feel it!

This is the curse energy born from my dark past!

Looking at the curse energy burning on his hand, he felt like crying. If he had to recall those unspeakable days every time he used curse energy, he wouldn't even need to fight; his dark past would kill him.

When he first learned that the world wasn't as peaceful as it seemed and that there were supernatural beings like curses and sorcerers, Hikigaya Hachiman was excited.

If curses are real, maybe the three creator gods are real too?

But after the excitement and the pain of losing his hand, he calmed down and thought, if he didn't even want to go to work, could he really decide to fight curses?

Working risks his life and dignity, while fighting risks his life. Between the two, working seemed better.

"Ha—if I say I don't want to learn sorcery tomorrow, will Hayashizaki kill me..."

Hikigaya Hachiman looked at the bathroom ceiling with a face full of melancholy.

...

...

Yukinoshita Yukino was really a strong-willed person.

"No matter how much you stare at your hand, you still can't do it," Hayashizaki teased.

Because of a little taunting, this kid had been struggling since dinner, but still couldn't succeed.

If she couldn't master curse energy when filled with negative emotions, she definitely couldn't do it now. Although Yukinoshita Yukino was still very angry at Hayashizaki, it was far from the despair and regret Hikigaya Hachiman felt when his arm was suddenly cut off.

It's not just a matter of talent but also a difference in understanding.

"Idiot, always trying to understand curse energy with existing scientific theories, how can you succeed?"

Hayashizaki couldn't help but tease as he watched Yukinoshita Yukino frown in deep thought.

"It's about feeling, feeling!"

With him constantly nagging in her ear, Yukinoshita Yukino felt even more annoyed. Her mind was in chaos, and she couldn't concentrate. If nothing else, she felt her negative emotions were maxed out.

"If possible, I hope you can give some substantial advice instead of babbling like a nonsense machine, just making people annoyed."

The girl pouted and said that she had never encountered such difficulties in her studies before. Even after racking her brain, she still got nothing.

I understand that we can't use existing scientific theories to understand something as mysterious as magic power, but this is all I can do. Just talking about feeling it, who understands that!?

"Tsk tsk, in the end, you still have to rely on others,"

Hayashizaki said leisurely.

"Call me sensei and let me hear it."

For some reason, Yukinoshita Yukino's face suddenly turned cold. She pressed her lips tightly and said nothing, continuing to struggle with her pale hands, ignoring Hayashizaki's chatter.

Huh? Why did she suddenly get angry?

Hayashizaki was puzzled by the girl's sudden change of expression, but with his high emotional intelligence, he took action—he forcibly took control of Yukinoshita Yukino's body.

'You!?'

"Don't talk, just watch and learn,"

Hayashizaki said, using the girl's body to demonstrate how to properly activate and use magic power.

"It's impossible to extract magic power solely from negative emotions; it's too troublesome. The correct way is to trigger magic power from slight emotions and control it, while also avoiding wasting magic power when emotions run high."

"Got it?"

'...Probably.'

Although she was prone to overthinking and being stubborn, Yukinoshita Yukino's intelligence was genuine. Her lack of success was only due to a problem with her approach. After Hayashizaki forcefully controlled her body and demonstrated in detail, the girl gradually understood the key points.

"Now you try,"

Hayashizaki said, returning control of her body to her.

It turned out that Yukinoshita Yukino wasn't just pretending. Although it took some time, a faint magic power eventually ignited around her, enveloping her body like a pale blue flame.

"Did I... succeed?"

Despite the rough process, the joy of success made her unconsciously smile.

But she quickly realized she was still angry, so she suppressed her excitement and expressionlessly washed an apple in the open kitchen sink.

Facing the parasite that always made her angry, Yukinoshita Yukino couldn't express her gratitude honestly. Coupled with her lingering resentment towards Ryoumen Sukuna, an ancient villain from a thousand years ago, this was the best she could do.

Soft-hearted but hard-mouthed.

What's with this girl? Is she a tsundere?

Hayashizaki chuckled inwardly while munching on the apple in her hand, silently accepting the girl's goodwill.

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