Chapter 4 - A Vow to Uphold

Part 1

It was the time when sunset began to dye the sky in its colours.

The siblings headed in a taxi through the New City towards the western business district. After getting off in front of a white building they hurried inside.

"You came, it's here."

Wary of Fuyuki, Haya who guided them was in student council president mode. Even though Fuyuki heard her real tone of voice in 《Aries》, she was still cautious.

The only, and a very large hospital in New City, Kiritou general hospital. The private room they arrived at was in a special ward, they entered .

"Ah, yahoo—, you two are here〜"

Rui had a raised upper body. It didn't feel like she was in a state where she was barely conscious an hour ago, Taiga stroked his chest in relief.

"Looks like you're alive and well. I wondered what happened when we were suddenly called to the hospital."

"Yahaha, sorry for worrying you."

"If you're alright, then that's fine."

For the time being, they were happy that Rui was safe.

When he looked around again, he noticed the hospital room was quite broad. The furniture and a pure white wall had a considerable sense of quality to them.

"It's a private VIP room. To prepare such a thing in one hour, as expected from a daughter of Kiritou."

"Fufufu, I'm acquainted with the director of this place. so I had it specially prepared."

Her tone changed to a polite one (Taiga didn't remember her cold tone anymore) as she stood a small distance away from the three of them.

Taiga wanted to learn what's happening as soon as possible, but he hesitated to ask in front of Rui.

So while Fuyuki was talking with her, he walked up to Haya and asked in a low voice.

" Rui really alright?"

"There's no need to worry for the time being. But the problems are going to start now."

" it."

Being said that it's alright only for the time being, part of his anxiety was revived.

"You said you prepared this room. But you're not acquainted with Rui are you?"

"I knew her name because she's a promising freshman, but that's all., right. She's staying at your house today, Taiga. Her parents sent you their best regards and leave her to you."

Although Haya answered indifferently, there was a glimpse of fatigue she couldn't hide on her face, it was probably mental fatigue——. If it was Iora who had undergone a sudden change, he could only sympathize with her.

"Are you alright?"

"Don't worry about me, worry about her."

Haya clasped both her hands soundly as she said that, and drew the line of sight of Rui and Fuyuki. She instantly pasted a perfect smile on her face.

"Let's go down the main issue. The state Saionji is in now, and the girl you three met, I'll explain all of it."

"First of all, Saionji's state. It's pretty poor to be honest."

Haya sat down on the chair and looked straight at Rui. Rui probably guessed it, and somehow accepted the declaration.

"...what do you mean by 'poor'? It looks pretty normal."

"Absolutely not. Saionji-san is in a state where her foot barely works right?"

"...Rucchan, is that true?"

Fuyuki didn't expect these words and stared at her.

Taiga as well thought that it couldn't be, and grimly stared at Rui.

"Uu... Kaichou-san. I told you not to tell them..."

"Recognition of the current situation is important. Besides that, the abnormalities are not only on the surface. Saionji-san, how much memory do you have left?"


For some reason Haya said those words with confidence. And not even Rui herself anticipated them.

" you still haven't realized."

"Please wait, Kaichou-san. What do you mean by memory?"

Fuyuki cross-examined Rui. Taiga had an idea. Memory——that word, it was only for a moment but Rui could not recognize him back then.

"Just what I said. Saionji-san, do you remember where you were last night?"

"Of course I remember."

"I see. Then a month ago——around the time where you graduated from middle school. What about that time?"

"Umm... after graduation ceremony I was with a friend... a, eh?"

She played with her friend——that's how it should be.

But she could not remember. Her friend's face was definitely in her memory, but she didn't remember her name. People around her were missing from the memory's landscape in her memory, as if they were cloth eaten out by a moth.

"What... why?"

"...looks like you can't remember. Looks like symptoms are still light, we'll see the results of the scan and you'll leave this place tomorrow evening."

"Hey, Haya! Come on and tell me already! What's happening to Rui?!"

Taiga hearing the roundabout conversation focused on the core issue.

If there's a progressing abnormality in her body, there's a need to investigate the cause as soon as possible. And that said, why was she talking leisurely about it.

"Brother, please calm down."


"Little Sister is also confused, but nothing will change even if you shout. Nothing good comes out from losing your cool."

He calmed himself down after taking a glance at Rui. She was laying straight on the bed and looking at him with a worried expression.

——Idiot. What are you doing worrying her instead.

As Taiga took a deep breath and waited, Haya projected a window from her terminal.

The projected Hologram looked like a pale sphere floating in the void.

"Now then to continue——Taiga-kun, do you know how the consciousness is maintained in Elysion?"

"Eh... yeah—what was it. The consciousness is downloaded in form of data and placed in a virtual body..."

"The outline is not wrong, but the answer isn't sufficient."

"Brother, wasn't it just taught in the class today?"


His lack of studying was exposed in an unexpected place.

"Lack of Taiga-kun's knowledge aside. Human mental structure is used as a base for generic biological information and memory. When you log in, your mental structure is transferred into the virtual body located in Elysion, after it's removed from the real body by arclight. That means, the virtual body is extremely sensitive to the mental structure and changes automatically. The body is very consistent with the mental structure, in other words, it's exactly the same as the one in physical reality."

In other words, it is a structure of soul and mind, your own body is left behind and that's inserted in an empty vessel——that's how Taiga interpreted it.

"This sphere is a graphical representation of a mental structure. Normally a mental structure is not beautifully one-coloured like this... but this is Saionji's mental structure now."

Haya summoned another window, and arranged it neatly right next to the first one.

The difference between the two of them was obvious.

"...this is, what does this mean."

" expected, it's not a laughing matter."

Taiga who was lacking knowledge about cyber-related things, could not understand the meaning of what the figures were showing.

But even so, he understood that the mental structure that was stained by crimson in some places as if eaten out was abnormal.

"A spiritual structure, in other words, it's a soul. It's like an engine that's required to move a human brain. If there's a problem with the mental structure, the body is affected as well. Also, so is the memory."

The part that was contaminated by red was smaller than one percent of the total. But while they were watching, although only by a little, a crimson part has eroded a normal part. Turning it blood red - 〈Crimson〉.

It reminded them of the girl with the huge sickle.

"...the cause is that thing?"

"To put it simply, she was injected with a virus. A virus that erodes the mental structure——although it said something like 《Jail》 or whatever."

"But, I've never heard of a virus that interferes with the mental structure! No, in the first place interfering with the human soul is commonly acknowledged as being forbidden!"

"Yeah, that's right. Because interference with Mind Crack."

It's not regulated by law. Rather than that, the laws are far behind the logic of Elysion.

Although there's a story about a special police department in charge of Elysion recently, but the country couldn't interfere much because of the four companies monopoly.

That's why a minimum of morals was required for those that work in the cyber world. Out of the things ethically prohibited——Mind Hack was a prime example.

"Mental manipulation... it sounds like that thing is really dangerous."

"I've heard stories that terrorists tried to develop and practice it. But in fact, I haven't heard of a single success."

"Because it's still a black box to us, we're unable to analyse mental information."

No matter how much technology progresses, the matters of the human heart aren't something that can be easily analysed. That's why 『Immersion devices』 are only capable of doing things to a certain extent.

"It's just as Fuyuki-san and Saionji-san said, we can't 『Interfere』 with it in a true sense. But a year ago, a certain company began studying it for the purpose of converting it into a military asset, and was able to artificially create a similar phenomenon. ...the centre of it became a certain girl."

Haya took a big breath and sighed, she started to talk again after fixing her posture.

"——a researcher affiliated with Kiritou Group, Asumi Aoko. My best friend who developed the AI 《Iolite》 together with me."

The past led to the present, the chains of cause and effect.

"Just as I told Taiga-kun in the specialized lecture today, Kiritou is an emerging power. The cyber market was dominated by three large companies before. In that market, Kiritou attempted to interrupt their supremacy and benefit from it."

"There's a lot of rumours about that. Like if it doesn't profit, your actions will be limited."

"That rumour is true, my father is such a person."

"I see, so that's where the mental structure interference comes in. It could derive enormous profits if it could be utilized as a weapon. However, Asumi Aoko was it? For her to develop it alone..."

"Aoko-san had an incredible top class talent."

Haya's attitude as she exposed the dark side of her household was indifferent. She just relayed the facts to them. Even though she appeared to be a bit worried about it, she couldn't afford to bother with that now.

", why is that damn virus in Iora?"

"I don't know that myself. The project was aborted in the first place, the virus should be unfinished as well."


"I've heard that all the data involved in its development was disposed of and lost. And even though it shouldn't exist anymore..."

"Let's ignore that for the moment. That reaper——certainly, it was called Iolite. What caused that runaway AI's rampage?"

"I don't know that as well. When I attempted to delete a program I didn't remember writing, which appeared between two scans, it suddenly started up in the middle of it and took that appearance."

The deletion was probably a trigger of it to start up, that's what Haya meant.

It was possible that program code was hidden, and set to appear with specific timing——with something like this.

But there were too many things to take in at once.

Now that Aoko was dead, the only one who could access internal information was Haya. Even if someone tried to access it without authorization, the barrier she developed with Aoko to prevent that wouldn't be broken so easily.

"Iora who went on a rampage, to borrow Fuyuki-san's words let's call her a reaper. The reaper has implanted 《Jail》 into the mental structures of twenty-three researchers from Kiritou before she ran away. You know what happened after that."

"What happened with those twenty-three people?"

"They were transported into hospital in an unconscious state. They didn't wake up after being left by her unlike Saionji-san, they completely lost their mental structure. Also... Saionji-san will soon be the same."


Confronted with the facts again, Rui lowered her face.

As if a thread was cut, she hugged her body tightly like she was losing feeling in it.

"The amount you were infected with was smaller thanks to short contact time, and I implanted an antibody program in your consciousness to reduce the erosion, but it doesn't mean its completely suppressed. You will be completely eroded by tomorrow."

Just when Haya finished explaining the circumstances indifferently, she had an interactive communication call.

After Haya saw the name displayed in the window, she frowned and said "Excuse me." before leaving the hospital room.

A silence dominated the room.

Rui lost her voice because of the situation she was in, Fuyuki clasped her hands gently comforting her best friend. And Taiga blamed himself.

"...It's my fault."

He squeezed the words regretfully. She was cut right in front of him.

It was a distance at which he should have prevented it, he should have power to block it, and because he awkwardly stood in one spot, it led to an irreparable situation.

"If I didn't stand there carelessly, the reaper wouldn't have hit you. If I was stronger, I could defeat that alone, I don't care if I were to be cut, Rui wouldn't be cut like that in front of me!"

"Taiga... that's——"

Although Rui wanted to deny it, she was stopped by Fuyuki's silence. Noticing anger swirling in the back of her eyes, she closed her mouth.

"Eight years, I've been training desperately for eight years, and still nothing has changed! What 『Save everyone in front of myself』! I couldn't even save one person in front of me!"

Fuyuki walked slowly towards her brother who continued to curse himself.

And she raised her right hand with all the strength she had,

"——stop spouting crap, shaddup, idiot Onii."

*slap*, a loud sound came out as his cheek was hit.

Taiga, surprised by her unexpected behaviour, looked up at the beautiful sky blue pupils that displayed anger.

"Ah, geez... Rucchan! It will be loud so please block your ears! Little Sister is going to preach to this idiot!"

"It's a hospital room so be as quiet as possible〜"

"Fuyuki, what are you sudden——"

"Be silent for a moment, Onii! Also, sit in seiza!"

Riled up Fuyuki went back to calling him 『Onii』 from 『Ani』. Partly because of the atmosphere, Taiga sat down on the floor after getting off the hospital chair.[1]

"Little Sister is so upset her head's gotten weird! It's all your fault? What kind of crazy nonsense are you talking about!"

"No, but——"

"It isn't just Onii, Little Sister is responsible for the fact that Rucchan turned out like this as well!"

"Let me say a thing as well, it's no one's responsibility. Rui-san jumped in by herself, the fact that it turned out like this is my responsibility."

Both his cheeks were pinched by Fuyuki, and her face approached his.

The beautiful sky blue eyes looked as if they were to suck him in, and she conveyed her thoughts to him straight.

"I don't know what kind of lifestyle Onii led at Renjou's. However, to Little Sister it seems like 『No matter what happens, I'll shoulder it by myself』 was decided from the beginning... and that, is annoying me a lot, it angers me to the point I can't take it."


His heart bounced at these words. It was a lucky guess.

『Renjou Taiga』 was a person who wasn't protected, but the one who did the protecting, he was a human who stood at the top. Depending on his actions people's life and death was decided. He had no choice but to shoulder everything by himself.

Fuyuki conveyed her thoughts further.

"I'll say it clearly. I don't know about the real world, but Onii is just a beginner in Elysion. Know your place. Also, understand one more thing, now you have Little Sister with you."

Even when he was blessed with strongest subordinates, Taiga was always alone. He had no people whom he could cry and laugh together with.

He only needed the strength adults requested from him.

"No matter how far you go, I will always stand next to you——please don't forget that."

——For some reason. When she said she will always stand by his side, he was incredibly happy.

He finally could whisper the words, "I'm not alone".

No matter where he ends up, with this he could still believe.


"Yes. What is it?"

Fuyuki smiled gently. He wanted to convey something to her, but he couldn't find appropriate words.

"...thank you, for being my little sister."

He put all his thoughts in such mundane words.

"Fufufu, Little Sister being your little sister is natural right? What are you talking about now?"

"Well I guess. But that's just what I thought."

They were separated for eight years, it was so long it wouldn't be strange if their hearts drifted apart.

Even so, she still had him in mind, with all of her heart. Taiga understood with his heart rather than his mind just how strong her feelings for him were.

"...ahh, come on, Brother is so cute!"

And, with that as an impulse Fuyuki came at him and hugged him with all her strength, while he was still sitting. Entirety of her small yet soft chest pressed against his face, and a sweet fragrance filled his nostrils.

"Mugha... wa-wait, Fuyuki?!"

"Seeing such weakness it's unbearable! OniiOniiOniiOniiOniii!"

His physical strength was in contrast with the fragility of his mind. That gap moved her heart.


Looking at the siblings by the bed, Rui closed her lips tightly. Even though, to be exact it was Fuyuki hugging Taiga, but it was all the same to Rui.

——Not fair.

The two of them had a special atmosphere between them, and she was so envious she couldn't stand it.

She wondered, if that was why she extended her hand grabbing Taiga's ear unconsciously.

"Eh? Ru-Rui? ——Ow, it hurts it hurts it hurts!"

She grabbed it tightly and pulled.

"Mu—, Mu—, Mu—!!"

"Wa-wait a second, it hurts! Did I do anything?!"

Taiga was confused because he was punished not knowing the reason. Rui just kept pulling and twisting his ear like a child without telling why. Fuyuki's gaze suddenly sharpened.

"...what are you doing?"

And, coming back unnoticed, Haya looked down on him as if he was garbage, with a good looking smile on her face.

"Um, no, this is..."

"A carnage? Two-timing is the worst."[2]

"It's a serious situation in a different sense!"

That façade, she definitely knew what's going on, and yet said that.

Fuyuki stopped hugging him, and Rui stopped pulling on his ear and sat straight. But she looked slightly angry. She sat up without explaining why she had been pulling on his ear.

"Looks like the poisonous air disappeared somehow, is it alright to continue the talk?"

"...go on."

Certainly, the tension caused by his sense of guilt disappeared. He wondered if that's what Fuyuki intended by acting like that——?

...I'm thinking too much into it.

Taiga immediately rejected that guess in his mind.

"Really, it's all because Brother said such things."

"Is that my fault?!"

"'s not Taiga's...fault......"


Suddenly, Rui's condition turned strange.

Her pupils unfocused, her body lost its strength and fell on the bed.

"Hey, Rui?!"

Taiga wanted to approach her in a hurry, but was stopped by Haya.

"Please calm down. She probably just fainted because the erosion has progressed, she will wake up soon."

He was relieved to hear that.

But it wasn't a state where they could be optimistic. Taiga asked Haya straight.

"Haya, what do we have to do to turn Rui back to normal?"

"...the method is very simple. I will create an antibody program that will destroy the cause of abnormality in Iora, the mental structures should all be released and restored. However, there are some concerns."

"Concerns... is there a time limit?"

"A time limit? What do you mean?'

"...the mental structure, in other words, if there's no soul it can't be logged into Elysion, she has to be a proper entity."

If the mental structure disappears, there's no recovering. Currently it's the common belief that there's some kind of connection between the mind structure and body.

That's why in Elysion, a bowl called virtual body replaces the substance required for mental structure.

"However, if 《Jail》 erodes the mental structure, the connection might be cut off."

"If the connection is cut off, is that bad?"

"It's very bad. Brother please think about it. You cannot return to the original location after that thread is cut. Even if the mental structure is intact, it doesn't mean anything if it can't go back to the body."

"Wha...... then, then Rui will——"

"Taiga-kun, calm down. It won't happen immediately. In Saionji's case the erosion isn't done yet, also there's still a possibility of re-connecting it after it's eroded."

He was somewhat relieved by those words. And, Fuyuki asked further details.

"In that case, do you know roughly how much time is left?"

"Unfortunately I don't know the exact time... but it won't be too fast."

If she doesn't recover her mental structure as soon as possible, there's a worst case possibility Rui will never wake up.

A day, maybe three days, even if he asks... he has to hurry anyway.

"And one more thing. Since there's a barrier around Iora, it's impossible to inject the program in that state. Someone has to destroy the barrier by attacking her..."

"The stage is 《Aries》, there's no choice but to do it by force... Brother?"

"I know... that's my role"

Taiga swore to her as she slept, and muttered the words with resolution.

Part 2

——She had a dream.

She felt as if she was floating on uncertain waters, and nevertheless, she felt at peace.

She continued to look at her memories with dulled thinking ability.

It were memories from the four last days, but even though the time was short the memories had a high density.

That time repeated again and again, and Saionji Rui continued to replay those last four days.

Suddenly, her field of view was dyed crimson. It seemed like it came to steal it.

No way. I'm not going to give it up.

It didn't hear her. The crimson continued to take away her dreams, and soon faded away as if satisfied. She wondered just how many times this 『Predation』 repeated.

The tape called memory, was literally eaten away little by little.

She was exhausted by being eaten away at, she knew that even as she slept.

Even so, just that, just those feelings, she will definitely not forget.

Thinking like that, Saionji Rui immersed herself in the memory.

Suddenly, she woke up.

"Hey, sleeping beauty. Are you awake?"


She turned in the direction the voice came from, she wondered if he kept watching her, it was the figure of ******* Taiga sitting down on a chair in a white room.


Weird... the information she should have was missing from her head. As she moved her gaze after being attacked by anxiety, what entered her field of view was a white wall and a darkened night sky.

"It's already night?"

"You slept for about three hours. ...that fake yamato nadeshiko, what kind of 『she will wake up』 was it. We were insanely worried..."

Taiga muttered under his nose and took out a plastic bottle filled with water from the refrigerator, and held it out to her. Rui was thirsty so she accepted it——but it dropped down on the bed.



Taiga caught the plastic bottle that almost fell off the bed.

...I see, my right hand is messed up as well now.

Somehow, she recognized the state she was in, as if she was talking about someone else.

There still wasn't anything wrong with her sight and hearing, she would go mad if that was the case——it wasn't a theory, but an intuition.

"...ho, then I'll help you drink it then."

Taiga opened the cap, and helped her drink the water while making sure she didn't choke.

Just because she couldn't muster much strength he moved, even though she could drink it by herself if she used both hands.

"Thank you, Taiga."

"You're welcome. How's your memory?"

"Nn〜it's more or less alright."

She was in a state that normally would cause fear to crush her, but she answered with a smile.

Beaming with a radiant smile blowing away the negative feelings, hiding her helplessness in the deepest corner of her heart.

Because she knew that's the only thing she can do.

『It's my fault』, she knew that was the only way to heal the heart of the boy in front of her.

"I see... and more specifically?"

"Nn〜 memories of middle school first year disappeared as if they never existed. Ah, and also I don't know Taiga's and Fuyuki's last name anymore."

"...isn't this serious?"

"That's why, tell me?"

"'s Tenryo. Tenryo Taiga, and Tenryo Fuyuki."

"Tenryo, Tenryo Taiga... Tenryo Fuyuki..."

Before the girl who tried to remember it, Taiga was also aware of his own powerlessness.

But it was not the time to regret. It's not possible for Tenryo Taiga to save her now. And because he can't do it, he needs to use this time well.

"Then——Rui. Umm... tomorrow, will you go on a date with me?"


Being suddenly invited 『?』 mark appeared as she smiled.

Next day, eight forty in the morning.

"Well then, I'm off."

Taiga sat on a chair in the dive room and fixed his breathing. Fuyuki was on the other hand sitting on the floor tired after working all night and just raised her hand seeing her brother off.

"Yes. Please send Rucchan my regards. Little Sister is so focused on work she doesn't have time to contact her. My apologies."

"I know. About that program, I leave it to you. ——Dive Start."

Taiga started up arclight, and his consciousness moved to Elysion.

The mental structure was as usual, transferred to the virtual body. But the log in destination was different.

It was not 《Aries》 which was currently sealed off, but a public structure anyone could enter for free.

There are many various types of structures.

It was just like Aries which was a game that used surplus processing power, but the amount it used was very small and barely around 0.1%.

Unlike a special structure like Aries, most of the city structures for public use mimicked reality. They were literally an existence that was a 『Second world』.

When it comes to the city the three of them lived in, the structure was referred to as 『Virtual New City』.

This virtual area imitated the real New City, a small world mimicking it.

Of course, if citizens couldn't access it it wouldn't be a public structure——that's what an urban structure was.

" I came here for the first time, but it is a mysterious place."

He felt light-headed for a moment, his virtual body was in front of the station.

The city entrance——this was the location everyone was sent to when they logged in to 『Virtual New City』 for the first time, the station. Though it was called a station, the linears were not running.

When he looked up, there a number of strange coloured cubes floated in the sky, displaying information and news.

Buildings, roads, everything, the futuristic city looked somehow surreal.

Those guys couldn't stop themselves from doing whatever they please, such a thing...

In fact, there's a lot of incidents where people fall into malnutrition after continuously diving for a long time.

Since he wasn't using a small headgear type arclight used at homes but one with life support system, continuous diving should not cause any serious consequences.

"Well then. Just as I've been told by Fuyuki, I came twenty minutes before the promised time."

In front of him, there was another visitor in the meeting place they decided together a day before.

"Why are you here already..."

Even though he intended to go over there before she came——but Fuyuki's advice was defeated. And, then she came over while waving cheerfully after noticing him.

Chestnut fluffy hair, a girl wearing irregular daring clothes.

Having a natural charm that attracted people's gazes, it was Saionji Rui.

Why were the two of them on a date at a time like this.

It's something they talked about yesterday, before Rui woke up.

"Role, is it... certainly, the only one who can fight back against it, is only Brother, but do you have a chance? Taking the previous battle into consideration, I don't think Brother has any?"


Although he said something cool, he was at a loss for words when he was told that.

Even if he was caught off guard, but he would be defeated anyway if he continued to fight like that. And, for some reason his body acted weird during the battle.

" didn't think about it. As expected."

"Well well, isn't that just like Taiga-kun. Making a rash decision and ending up looking uncool."

He noticed it just now, but Haya and Fuyuki were quite similar.

"But there's no need to worry. This wonderful cute Little Sister will think about it. ——Give Little Sister a day, and I will determine the reason for Brother's malfunction, I'll do something about the difference in strength."

Fuyuki looked straight at him, and that look increased the feelings of helplessness he had.

Twenty-four hours. During that time, he could do nothing but look at his best friend, Rui to break in silence.

Even so, Fuyuki would not budge.

In order to save her, in order to avoid failing no matter what. She would not budge.

Because Taiga understood that, he prepared himself.

"...I get it. I leave it to you, Fuyuki."

He left it to her. And his little sister went home immediately.

"I need to complete the antibody program as well, so excuse me. I will be done by tomorrow as well."

"I see. So, what should I do now..."

He couldn't spend time not doing anything.

Looks like they will be skipping school tomorrow, he thought about going to train after all, but Fuyuki proposed another plan.

"Brother, please stay together with Rucchan the entire time. She will be insecure and anxious alone. I don't mind if you go on a date or something you know? I give you special permission."

"D-date? No, but Rui can't walk..."

"If it's that it'll be alright. Kaichou-san, does this hospital lend virtual bodies that are operated by thoughts?"

"One can be prepared right away."

"It's decided then. Brother, tomorrow go on a date in Elysion tomorrow."

Their conversation skipped a lot of steps. Well he was worried about Rui, and he wasn't against going out together... still he couldn't help but get nervous considering it was a date.

"It will go well, Little Sister will give you advice. In exchange, please go on a date with Little Sister later, okay?"

That's it. Recollection end.

Taiga rushed over and uttered a word of apology.

"Sorry, did you wait long?"

"Mm, no, Rui-san just arrived as well."

The male and female roles were perfectly reversed from what Fuyuki told him. He couldn't calm down feeling guilty, he started the day he was supposed to spend with Rui thinking like that.

An innocent smile like usual, and her clothes were hot pants and a tank top.

Meaning, Rui wanted to look attractive today.

...did she change for me?

He didn't know how to call it, but today she was——cute.

It didn't mean she isn't normally cute. It meant... that a very pretty atmosphere surrounded her body.

He wondered if that was the magic of a date.

"...uh—umm, is your body alright? The thought-operated virtual body, was it?"

"Yup. It was difficult to move at first, but I've got used to it."

Rui moved her hands she couldn't budge in the real world, to show him.

The virtual body she was using was one often used in hospitals, it's a virtual body working on a special mechanism allowing it to move by using images in a human's head. It's mainly used for people with disabilities.

——She, who cannot move in the real world anymore, can move freely in Elysion. Realizing what he sees right now is just an illusion, his heart ached.

"Now then... let's go."

Shaking off that sentiment, he held out his right hand.

Even if you don't cross your arms, at least hold her hand——just as Fuyuki advised him.


Her cheeks flushed slightly, Rui overlapped her hand with his. And their fingers firmly entangled, this was the so called lovers tie.


Rui laughed slightly embarrassed for a moment, looking very lovely.

Because she was so attractive Taiga turned away when they started to walk to hide his bright red face.

——Just at this moment, he wanted her to forget about reality and enjoy herself.

While feeling each other's warmth from their connected hands, their date began.

From that moment, the two of them toured a lot of places.

Starting with window shopping, the two had a good time at karaoke and aquarium, after which they took a break at an open air café's terrace.

Above a cup of tea that was a combination of taste data, Saionji Rui observed the boy in front of her.

...super cool, well not really. But I wonder why? My eyes are attracted to him. The difference between the front and the back, I wonder if I like the gap between his everyday self and the feeling he gives off occasionally?

She had a strange taste, even if she said so herself. It was a pretty dangerous choice.

Because her memories were ragged out, she didn't know much about their relationship before, but somehow 『Saionji Rui』 felt he was someone she could get along with.

In a broad, and shallow sense. She thought to herself he might be 『Special』 to her.

And, noticing her gaze, their eyes met.

"What is it? Is there something?"

"No〜 Rui-san is pretty strange, I wasn't aware I was staring at you〜"

"If Rui is strange, then both me and Fuyuki would be categorized as madmen."

"Ahaha, that's not true!"

"I wonder about that. At the very least, the environments we were brought up in was abnormal."

"Nn〜 it was something like special forces or something right?"

"...asking about it while being perfectly calm is amazing but... calling it special forces, it isn't all that wrong. I saw guns and military drones on a daily basis, it was a place people killed each other in reality. The place I was taken to... well, was the worst."

Even so, he didn't think about the everyday life he lost.

Because he was going to go back there someday——that's what he decided in his mind, he had a 『World he should return to』 so he didn't despair.

" probably heard about it from Fuyuki, but I was in unexpectedly old fashioned home."

"Geez. Every country has unmanned weapons as their primary force nowadays, for people to go between such things, even if you trained it's some insane stuff."

A place where monsters with abnormal physical ability met.

Taiga didn't criticize the Renjou household that much. He learned sword techniques, and observing people around him he learned to handle and hone his body.

"Can it be, that you were bullied?"

"...why do you think so?"

"Well, somehow. You had kind of a pained look. I wondered if you went through some bitter experience, or something like that."

She's sharp.

His expressions barely changed, and yet he was read this precisely.

"Well, it's humans. There's always some guy who hates you and might hurt you. ...though I repaid him after becoming strong."


At that moment a clerk brought a strange object. It was a pile of fruits and ice cream that looked like an inverted triangle, and for some reason it didn't spill out.

"Sorry to keep you waiting. It's the special parfait you ordered."

"Ooh〜 it's here, its here!"

"Eh, what's this. A parfait... is that a joke?"

"Nfufufu〜 because the object has specified fixed coordinates it will not collapse."

A huge parfait was soundly placed in front of them after arriving. Although its appearance was worthy of being called special, but no matter what, that was over the top.

"Hmm... this is also a combined program stimulating the taste. Though when it isn't placed in a belly, it feels somewhat creepy."

"Hmph〜 stop thinking like that. Taiga should eat some as well. It's delicious you know?"

"...well then, just a bite."

"Yay, it's here, come on, a—n!"

Rui scooped up a mouthful, and held it out to Taiga.

"Wai- Rui?!"

"Hohoo, you see that's the kind of store this is."

He suddenly noticed that around them there were a lot of couples, some of them were eating the same parfait, and some were drinking stereotypical 『Couple Juice』 together.

But——her cheeks were red as she held out the spoon, and he noticed that her hand was trembling from nervousness, so he couldn't say anything.

It was just a moment later, but, he made his decision and ate the piece of parfait that was held out.

"'s delicious."


He thought it would be just sweet, but it wasn't so. It was cold and sweet spreading in his mouth. It wasn't only the taste that was programmed, there was also an after-taste and refreshing fragrance of fruits drifting around.

"...ehehe, it's an indirect kiss."

"Goouh?! Y-you?!"

"I wonder if rather than with Fuyuki, your first experience was with Rui-san?"

"...excluding the time we were kids, it's my first."

Of course it was with Fuyuki. Rui knowing that, looked somewhat regretful.

"I see. Looks like I can't win against Fuyuki after all〜"

"I don't think it's a matter of winning or losing you know?"

In the first place it was talk about when they were kids. Not something they did consciously.

"That might be so. But... I just wanted to be number one."

Especially, when it came to the person she liked——but she didn't have courage to continue like that, she as of now couldn't say that yet.

Wanting to shake off those heavy thoughts from her mind, she changed the topic.

"Speaking of which, when did you become friends with Kaichou-san?"

"Nn? Ah—... we met on the specialized course by chance. And we spoke quite often after that."

"So that's how it is. For some reason Kaichou-san, treats Taiga and Rui-san differently〜 or so I was thinking, I wonder if it's my imagination? Even though she's your senpai you get along with her really well."

"...I-it's your imagination. Come on, let's hurry up and go to the next location."

Faced with her sharp questions, Taiga changed the topic. Even though Rui had seen through him, 『I'll ask some other time』 she thought as she scooped some more of the parfait.

At the same time, in Kiritou Academy's structure.


A small sneeze echoed.

Haya continued the development of the antibody program while sitting on the sofa in her room, 『A cold at a time like this?』 she thought and examined the vitals of her body.

"All values normal... I wonder if someone is gossiping about me."

She assumed it was some researcher... or it might be him. She took a small break from work until she settled down after thinking something unnecessary.

As a lot of fatigue had accumulated, she laid down on the sofa and daydreamed while looking at the ceiling.

...I want to return to the laboratory, but I would probably be surrounded by other researchers and questioned.

Because, blocking a large structure like Aries was unprecedented. Though at that time there was no other way than to do that, the reason didn't matter.

The fact that she developed that AI would add fuel to the fire as well.

Currently, Haya was in a delicate position in the company.

"Because of that I don't have access to the facilities... seriously. Even though there's no time!"

One day. It was the grace time the company gave her.

If the situation doesn't improve Iora will be destroyed——she will lose. Last time she won the negotiations.

They were people who want to see results above anything else. There's twenty-three unconscious people, so they didn't want to destroy her right away.

If it was exposed that Saionji was subjected to 《Jail》 it would be bad. It would damage them a lot if news that they allowed a civilian to get involved in it got out.

The forced transition she did already stood out. If it came out to the public it would cause a scandal involving Kiritou——that's why the higher ups left it to her.

They wanted to avoid any bad rumours about Kiritou. And absolutely avoid scandals. Although it was as if she put a rope around her own neck, she got a chance to save Iora.

——She had to stick with it. That's what she thought. Not because she was her developer.

Because Iora was her dream.

Because the girl named Kiritou Haya was always lonely.

She could not make any friends because of rumours about her household. The only ones who approached her were adults who wanted to get closer to Kiritou.

Act like an adult——that's what her father, who was on the top of the company ordered her. She was instructed not to give anyone a chance to take advantage of her, and like a tyrant, forbade her from acting childish.

As the person in question, Haya, grew up, she got more and more isolated from the environment even if she didn't intend to.

That's why, that was the only dream she had.

——She wanted a friend.

As she grew up hiding her childishness behind an adult mask, she met someone who had similar thoughts. Asumi Aoko, and started a project.

Making an existence she could be friends with——a virtual personality with emotions, the development of project Iolite.

That's why she had to protect it. The form of a dream she had together with her late friend, even more so now that she has people who supported her, she has to protect it no matter what.

"...just wait. I will definitely save you. No matter what I have to do."

Haya said those words even though she knew no one will hear her anyway, and resumed work.

They somehow managed to eat the huge parfait together, it wasn't something one person could eat. And then they went on the streets once again.

They enjoyed their time in a relaxed manner walking around, Rui showed interest in the accessories arranged on the stall.

"Waa— this one is wonderful..."

Rui took a pendant shaped like sun in her hand. The design was quite elaborate, even Taiga who wasn't familiar with this kind of thing was impressed.

By the way, even though it's called a stall, they didn't sell anything in there. It was a place that could be used for sampling things, it was a mechanism that allowed you to order the thing in the real world.

"That's certainly beautiful. Also, it would look great on Rui."

He looked at its price. It was a little high, but if it was just that much it should work out.

"I'll buy this. Send it to this place."

"Eh...? Nonono you can't! Aren't you short on living expanses?"

"It will work out if I fast a little. Also, it's a present not only to commemorate the date, but also a sign of gratitude."


"Ever since I moved, I was always taken care of by Rui. This is something like an appreciation gift... thank you, and I'll be in your care from now on, that's why please take it."

He conveyed his feelings of gratitude to her upfront.

He really was always taken care of by Rui. Things like school, meals, Aries, and also that she became Fuyuki's friend. He couldn't thank her enough.

He was honestly embarrassed, but it was something he had to say properly.

The person in question, Rui was dumbfounded. It was nothing special to her, she just did what she could do——and yet as she was being sincerely thanked for that, she thought he was very cute as he said that.

...I feel that I can somehow understand what Fuyuki meant when she said he's cute.

At the same time, she understood she can't refuse his feelings.

"I see. Then, don't hold back with your present."


It would arrive in two days, for the time being until the purchase procedures were done, she got data with the specification of the accessory as a bonus. That meant she could use the same fashion in both the real world and Elysion.

"Ah. This is perfect. Taiga, put it on me."

"Eh? N-no at least do that yourse——"

"Come on, hurry up hurry up."

While maintaining the momentum, she got close to him by a step and removed the pendant's clasp.

As Rui closed her eyes and looked up, looking as if she was prepared for a kiss, Taiga moved his hand behind her neck trying not to stare at her as much as possible.

He tried to place the pendant on from the front. But, it didn't seem to work because he was too stiff.

"Taiga—. It will be hard unless you get closer you know?"

"Uu, n-no, I know that but..."

But if he approaches her any more than that... he would get in close contact with various things. Especially with her large breasts——is what he thought but couldn't say.

However, so as not to make Rui wait any longer, after a few more seconds of struggle, he made his decision and approached her by taking a step forward.



From a third person's point of view. It could only look like a couple hugging each other. That's how close the two of them were. Soft twin hills of size incomparable to Fuyuki's pressed against him slightly above his stomach, and a happy feeling spread through his body.

I knew they are big but... t-this is dangerous...!

It wasn't just the feeling of her body, the sight and the smell were dangerous as well.

Looking down from above, her body was destructively attractive, on top of that her chestnut fluffy hair smelled very good. If he was to compare it... right, it would be like the sun. Like a warm and soft smell of daylight.

It would turn bad if he continued to stay like that. Taiga fastened the pendant's clasp in a hurry. His sense of smell and touch were stimulated like crazy as he did that, and his spirit was worn out in various ways by the time he finished.


Even so, seeing her smile was worth doing that hard work. That's what he thought.

Rui played with the pendant happily. Although she smiled happily as she looked at it, it suddenly darkened.

"Looks like it's about time..."

They both knew it. No matter how much fun they have, it will eventually come to an end. While there was still light left in her heart, she declared.

"...there's one last place I want to go to."

Rucchan, is probably at her limit...

Fuyuki continued programming at a tremendous speed without moving an inch from the spot, or looking away from the screen even for a moment ever since she saw Taiga off, she checked the time.

Four p.m. ——it was the time Kiritou Haya estimated as a limit. Fuyuki looked at the ceiling and thought about the girl who was about to disappear in a distant world.

Tenryo Fuyuki's only friend, the only friend of a girl who used to be Karasuba Fuyuki, Saionji Rui.

A person who reached out a helping hand to her after she was torn apart from her beloved brother, her important best friend.

"...don't worry and please wait. I'll save you right away."

Fuyuki went back to work after murmuring that.

Right now there's one thing she had to do, she couldn't think about anything else.

"Just a little more, one more stretch and it's done."

With her sky blue eyes shining, Fuyuki plunged into the sea of electrons.

"Yup. No matter when I come it's always beautiful here〜"

In the scenery dyed in scarlet, chestnut hair danced in accordance to Rui's movements, it glittered reflecting particles of light cast by the setting sun.

The light scattered every time her hair flowed in the strong wind, wrapping her in a gentle and warm ambience.

"...yeah, certainly it's beautiful."

There is a place I want to go to——saying that she brought him to a viewing platform on a small hill in the outskirts of 《Virtual New City》.

There might have been some people there if it was a holiday, but there was no one there during daytime on a weekday. Also it wasn't reality so there were no people who would come over on a whim.

There were only two of them on the viewing platform looking down on the city.

Taiga and Rui stood side by side looking at the fantasy-like city.

"...why, do you think I chose to come here last?"

The words she murmured melted away carried by the wind. Still, they easily reached him, Taiga answered her while looking at the scenery of the city spread below.

"Because the scenery is beautiful, I guess."

"Unfortunately, a miss... but isn't it? It's not like it isn't beautiful. But the answer is incorrect."

Only last pieces of memory were left in her head, even the recent memories were becoming a mess.

Even Saionji's Rui personality was becoming ambiguous. Together with her thoughts, her virtual body slowly stopped to respond and move.

The appointed time, was about to come soon.

"One day. When I found a person I like, I would end the date here——that's what I decided. I'd prefer if it was reality, but in this state it can't be helped."

"Isn't it all right. After returning to your body, you can go there together with the person you like."

"Ahahaha, you don't get it at all do you〜 Taiga. It's important for it to be the first time. Seeing the sunset together... it feels like fate. Wonderful isn't it?"

"So it's like that."

"That's how it is... can we sit down? In fact, it's a bit hard to stand."

They sat on a bench, and looked at the sun sinking behind the horizon in a relaxed manner. Then, Rui placed her head on Taiga's shoulder.

"....................................It's scary, after all."

He heard a small voice.

"Even though, I should be prepared for it... but... the fact that I might disappear... is scary..."


"Why did something like that happen!! It should have been just a normal day like usual!! Even though, ever since Taiga came every day became more interesting and fun, why do I have to go through something like this?!"

The chain of emotions held in by force burst, it exploded.

Not knowing why was it her, why wasn't it someone else——even though she knew it was synonymous with hoping for someone else's misfortune, she couldn't help but think so.

Tenryo Taiga was a boy who was crushed once in reality, so he understood her pain.

"...I don't want to disappear..."

Large tears fell one after another, fear that has been suppressed until now, the things she was afraid of, surfaced one after another.

——Because he didn't want to see such a face, that's why he's gotten stronger, didn't he.

"...the one who should have been cut is me, the one who was supposed to fade away should be me. Because you protected me, I can be here. That's why—— the fact you were the one cut, I'll make sure it wasn't meaningless."

There was a meaning in the fact that Tenryo Taiga remained and not Saionji Rui, he will prove that there was a reason for it and it will lead to something.

"——I swear. That's why wait for me. It'll be over soon."

He will definitely save her——he won't allow anyone to be sacrificed.

The moment he feels that there's a need to sacrifice something precious, his existence will become meaningless.


Sky blue eyes looked straight at her, as if sucking her in. It reminded her of a majestic sky encompassing everything, Rui made a small sigh.

Yeah——with this, I'm done for〜

There was no doubt about it.

Confirming it, while on verge of disappearing was just like her.

Unnecessary things like suspension bridge effect came to her mind, but it didn't matter. That's why she saw him off with a wonderful smile on her face believing in him. Because she will see him again soon.

She wiped the tears that spilled.

In the beautiful orange sunset, the scarlet colour burned in her heart.

Here and now, certainly in her heart,

"———Yup. I will be waiting, my Prince."

Saionji Rui closed her eyes.

Her eyes closed as if she was asleep, they wouldn't open no matter what.

Basking in the sunset's light, Taiga continued to hug her body as strength gradually left it.

Translator's Notes and References

  1. Ani here is usually translated as Brother, which is a kinda-mature way of calling an older brother and probably the term that's most similar to English "Brother", Onii is more childish way of calling an older brother, so it's usually distinctively left untranslated.
  2. Shuraba – In other words, a battle, carnage, hell, that's how battle between girls over one man is sometimes referred to in Japanese

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