Demon Slayer: The Journey That Began When I Became Yoriichi's Sister

Chapter 563 The Evil Frankenstein

Yoruichi was somewhat speechless: "You actually said it was interesting..."

Yuko, holding her teacup, shrugged and said, "There's nothing I can do about it. Yoruichi, you don't put any pressure on me at all~"

"Hehe." Yoruichi gave a forced, insincere laugh.

After the afternoon's commotion at the dojo subsided, night quietly enveloped the Soul Society. After dinner, Ikuko trained with Yoruichi at the dojo for a while, then washed up and returned to her room.

Yuko dried her hair, wrapped a headscarf around her neck, sat on the tatami mat, and drew her Zanpakuto to examine it.

"Honestly, all I did was say a few words to her this afternoon."

"Is it really necessary to go to such lengths?"

The evening training was initiated by Yoruichi herself, and Yuko knew what kind of wicked idea Yoruichi had in mind as soon as she mentioned it.

As expected, Yoruichi demonstrated her strength as captain during the evening training session.

The ultimate Instant Step made it difficult for Yuko to catch a glimpse of him, and Prism even had difficulty touching the hem of his clothes.

“You agree, right, butterfly?” Yuko gently stroked the blade of her Zanpakuto.

The butterfly trembled slightly, as if in response to Yuko.

Yuko muttered to herself, "I still think it's your problem. If you had told me the real name of your Bankai, I probably could have beaten Yoruichi to a pulp tonight."

The slightly trembling blade stopped instantly, seemingly unwilling to participate in the topic.

Yuko rolled her eyes slightly upward and began to maintain her Zanpakuto.

A moment later, Yuko raised her blue-purple Zanpakuto above her head, where it seemed to gleam with an oily sheen under the light.

"I've never even maintained my own knife this meticulously," Yuko muttered. "Shouldn't you at least do something to show your appreciation?"

The butterfly remained motionless.

"Or should I consider myself successful if I guess just one word correctly?"

"..."

"I'll give you one word at most, two words, okay?"

"..."

Yuko packed her things, took off her headscarf and hung it aside, then lay down on the tatami mat, ready to go to bed.

“The Butterfly Without Form…” Yuko murmured softly, her fingertips unconsciously tracing patterns in the air, as if she could sense the existence of that strange space.

The Zanpakuto lay quietly beside the pillow, its scabbard emitting a subtle, understated blue-purple glow even in the darkness.

Communication with the butterfly went exceptionally smoothly, probably because the other was exactly the person she had always dreamed of. That bond, originating from the deepest part of her heart, seemed to naturally transcend the usual adjustment period between a Shinigami and a Zanpakuto.

Yuko lay on the bed, picked up the Zanpakuto beside her pillow, raised it high, drew the sword, and her golden double pupils seemed to glow slightly in the darkness.

"To be honest, I don't care about Zanpakuto or anything like that, but your existence itself is the most precious gift."

She thought of that girl in the Butterfly House corridor in her inner world, swinging her toes, who seemed to be a fusion of her and Shinobu's shadow.

As if understanding Yuko's feelings, the Zanpakuto's blade glowed with a faint, purplish light, as if responding to her.

"Phew~" Yu Zi breathed a sigh of relief. "Butterfly, I'll have to rely on you for a long time to come."

The deep purple light shone even more brightly.

"Go to sleep."

Yuko smiled slightly, placed the Zanpakuto beside her pillow, and slowly closed her eyes.

In the stillness of the night, as her thoughts drifted between sleep and wakefulness, an extremely subtle fluctuation of spiritual pressure, almost blending into the night breeze, like a pebble thrown into a calm lake, instantly jolted her awake.

Yu Zi suddenly opened her eyes, her golden double pupils precisely locking onto the window of the room in the darkness.

That spiritual pressure... was suppressed to the extreme, almost undetectable. If it weren't for her own perception of the surroundings being far beyond that of ordinary people, she probably wouldn't have been able to detect it.

However, the feeling of this aura is...

"Urahara?" Yuko silently raised an eyebrow, a playful smile curving her lips. This guy had sneaked over here in the middle of the night.

What are you planning to do? Does Yoruichi know?

Yuko didn't move, not even her breathing rhythm changed, she just lay there quietly, as if she had really fallen asleep.

The figure outside the window paused for a moment, seemingly checking the situation inside. Then, without making a sound, the window was opened a crack. A head wearing a black trench coat, with the brim pulled low, peeked in. After confirming Yuko's presence, the figure, whose face was difficult to discern in the darkness, quickly slipped inside.

Kisuke Urahara's gaze swept quickly across the room, finally settling on the sleeping Ikuko. Like a nimble Yoruichi, he smoothly turned and closed the window.

However, just as he closed the window and turned to look at Yuko, he suddenly realized that Yuko had already sat up, and he couldn't help but shudder.

"Haha... Yuko, you're awake?" Urahara chuckled twice, quickly adjusting his expression and reverting to his silly look. "Great! I was worried you were sleeping too soundly."

"You're putting on quite a show; acting all sneaky doesn't seem like a good person." Yuko glanced lazily at the Zanpakuto beside her pillow, then looked at Urahara. "So, what do you want?"

"Should I call Yoruichi over to help you?"

"Shh!" Kisuke Urahara jumped, quickly shuffling over. He put a finger to his lips, nervously glancing left and right, and whispered, "Sister! This is the one thing we absolutely mustn't do! If Yoruichi finds out, she'll kill me!"

"With your current attire, I think it's practically trespassing into a girl's room. Killing you would be too lenient," Yu Zi said, looking at him expressionlessly.

At this moment, Kisuke Urahara was wearing a black trench coat, which almost completely blocked the leakage of spiritual pressure. If it weren't for Ikuko's special perception as a demon, she probably wouldn't have known when Kisuke Urahara entered.

Kisuke Urahara scratched his head somewhat awkwardly.

Yuko crossed her arms: "Give me a reasonable excuse."

"An excuse is... ugh! It's not an excuse!" Kisuke Urahara came up behind Ikuko and began to massage her shoulders in a fawning manner. "Um, Ikuko, Miss Ikuko, Sister Ikuko, actually, it's like this..."

Yu Zi raised an eyebrow and casually slapped his hand away.

"Are you going to tell me or not? If you don't, I'll call for help."

"Alright, alright, I'll tell you, I'll tell you." Kisuke Urahara quickly came to the opposite side, sat down, and smiled obsequiously. "Um, didn't Ikuko mention this before?"

"May I take a look?"

Yu Zi raised an eyebrow. "I'm not asking you to study it, but I can give you some of my body tissue."

“That’s it!” Kisuke Urahara chuckled, rubbing his hands together like a fly. “I wonder what it will be like now…”

Yuko squinted and said, "You...you wouldn't be thinking of using my flesh and blood for some kind of evil experiment, would you?"

That's why I didn't dare come over during the day.

"What an evil Frankenstein monster."

Kisuke Urahara's expression changed slightly: "How...how is that possible!"

"It's like this, Yuko-nee, as you know, I'm very interested in your... um, unique physiological structure..." Urahara Kisuke rubbed his hands together again, looking at Yuko expectantly, but when he saw Yuko's expressionless face, he couldn't help but lower his head with a look of dejection.

Yuko drawled, "However..."

Kisuke Urahara subconsciously looked up.

Yu Zi smiled slightly: "I think your research is not the kind of experiment that would harm ordinary people."

"How much do you want? Should I cut it myself or will you cut it?"

As Yu Zi spoke, she raised her left hand and used her right hand to make the incision, slowly placing the bluish-purple blade on her fair arm.

The butterfly seemed unwilling to hurt Yuko, so it trembled slightly in resistance.

Yu Zi raised an eyebrow: "Alright, alright, it seems my butterfly is a bit resistant to hurting me, so you'll have to do it yourself."

Ikuko put away her Zanpakutō and stretched out her hand towards Urahara Kisuke.

Kisuke Urahara was momentarily stunned.

"What are you standing there for? Isn't one arm enough?" Yu Zi raised an eyebrow.

Kisuke Urahara took a deep breath, hesitated for a moment, and said, "I've recently been conducting a very important study. It concerns the essence of the soul, and may even touch upon something... taboo."

“This taboo may transcend the boundaries between Shinigami and Hollows, but I haven’t been able to make any progress in this research lately. I hope that your flesh and blood, Yuko, can give me some clues.”

"Taboo? That sounds like something illegal," Yu Zi retorted.

Kisuke Urahara said somewhat awkwardly, "Yes, it is indeed something that is prohibited from being researched."

Yuko looked at him speechlessly. In fact, when Urahara Kisuke came to her door without permission, she had already guessed his purpose.

After all, Kisuke Urahara's previous desire for her flesh and blood was not an act.

“Although it doesn’t sound like a proper experiment…” Yuko stroked her chin, “I can tell that you’re not trying to gain power or do anything bad; it’s just driven by pure curiosity.”

"So, I agree."

"But I must warn you, the boundary between Shinigami and Hollows feels a bit dangerous to me. Just don't fall into a trap."

Yuko, after all, has a modern mindset. During her time in Seireitei, she came to understand what Hollows are and what their relationship is with Shinigami.

Simply put, they are two completely opposite species.

After death, if the soul is not redeemed, it becomes a void, a completely negative existence.

Kisuke Urahara, in order to study the boundary between Shinigami and Hollows, must study both types of existence.

In a modern comic book storyline, this might mean being killed by a monster they've researched, resulting in a complete disaster.

So Yuko felt she needed to remind him.

"Why?" Kisuke Urahara couldn't help but ask.

He had clearly told Yuko his purpose, so why did he agree to it?

"Your ears must be fine, right?" Yu Zi pouted. "I told you, you're just trying to satisfy your curiosity, not to do anything bad. As a friend, I'll support you if I can."

Urahara Kisuke looked at Ikuko with a complicated expression.

Yuko shrugged: "Of course, if you accidentally cause trouble, just remember not to push me out."

Urahara Kisuke: "..."

Yu Zi's expression turned serious, and she said solemnly, "I have to remind you again, never do research that is beyond your control."

After all, that research didn't sound very promising.

Kisuke Urahara pondered for a moment, then nodded slightly: "I know."

Yu Zi smiled slightly: "You're not a child anymore. Do whatever you want without worry. Just remember to take responsibility if something goes wrong."

Kisuke Urahara: No, although you are older and I am very touched, what you said next is hard to believe.

Yuko stretched out her arm: "You do it yourself."

"Don't worry, even if I lose my head, it won't bother me."

Kisuke Urahara's lips twitched slightly: "We don't need that much, just a little flesh and blood will do."

He was just doing his research to clear his head.

"Well, you can decide for yourself then." Yuko frowned and handed her hand to Kisuke Urahara.

Kisuke Urahara licked his lips, then hesitated for some reason.

To be honest, he really wanted to study ghosts.

But on the other hand, he didn't want Yoruichi to know.

On the other hand, he is now a little uncomfortable with Yuko's generosity and feels embarrassed to take advantage of her.

Just as Kisuke Urahara hesitated, drawing his Zanpakuto and intending to cut off a small piece of flesh for research, the door was violently kicked open.

"Kisuke!" Yoruichi's angry voice came from outside the door, and the paper sliding door was kicked open and crashed towards the two of them.

Yu Zi gasped, immediately pulled her hand back, and hid behind her.

Kisuke Urahara wasn't so lucky; he was slammed against the wall by the sliding door and stared at the doorway in terror, covering his face.

"Yoruichi, let me explain... Pfft~"

Before Kisuke Urahara could finish speaking, Yoruichi flew in from outside the door and kicked him in the stomach.

"Ouch~" Kisuke Urahara knelt down, clutching his stomach.

Yoruichi, her face ashen, demanded, "What are you doing sneaking into a girl's room in the middle of the night?!"

Soi Fon, who came running at the sound, also looked at Kisuke Urahara with disdain.

"I want to explain."

Yoruichi interrupted him: "Kisuke, I told you, you're playing with fire."

Kisuke Urahara paused in his speech.

Seeing the awkward atmosphere, Yu Zi quickly stepped in to smooth things over: "Hey, don't be angry. He didn't come to raid me at night. He just came to chat with me."

Yoruichi glared at her: "Shut up."

"I……"

Yoruichi said calmly, "Salary."

Yuko gave Urahara Kisuke a "good luck" look.

As Kisuke Urahara's friend and former boss, Yoruichi naturally knew his friend well and roughly knew what kind of research he was doing in private.

That was something the Seireitei forbade to research, but Yoruichi, as a friend, could turn a blind eye.

But Yuko is really different.

Demons have never existed in this world before, and it's unclear what will ultimately happen, but Yoruichi is certain that it won't be anything good.

So when the three of them brought it up last time, they jokingly said they had already refused.

Unexpectedly, Kisuke dared to sneak up on us this time, even wearing clothes to eliminate spiritual pressure. If she hadn't happened to pass by and overheard him, she might have been kept in the dark.