Chapter 10: The Key and the Sword

On board the bridge of the airship Fraxinus, the main monitor displayed a view of the lookout post atop of Tenguu Tower, with shards of glass flying out everywhere. At the same time, a fierce alarm erupted from the speakers.

"...!? This is——"

"Two strong Spirit waveforms have been detected! One of them shows values of Category E!"

"What...!?"

After hearing Minowa's words, Kotori knitted her eyebrows.

Spiritual wave reaction, Category · E. In other words, rather than a normal Spirit reading, an entity endowed with the spirit power of an Inverse Spirit had appeared.

Despite that, the present situation was not completely unexpected. After all, Tohka, who had inverted, should currently be in the observatory.

No——using the preposition in would have been inappropriate.

On the primary screen, two Spirits leisurely stood upright against the glass curtain wall, their lengthy windswept hair dancing in the breeze.

"...!"

As Kotori's attention was focused on the monitor, another loud noise reverberated in the bridge once again.

It was the echo of a piercing, blood-curdling siren that roiled the surrounding air.

However, it didn't originate from the ship itself. The spacequake alarm was issued only after observing the spirit power of the two.

Usually, the spacequake alarm was sprung by observing the spatial fluctuations that occur when Spirits from the neighboring world appear in this world.

Of course, in this country, the AST would not let these abnormal spirit wave readings go unnoticed.

The crowd on the street immediately dispersed. Everyone was in a hurry to evacuate to the nearby shelter.

"Kuh..."

Kotori glimpsed at the scene reflected on the main display before making a frustrated face while clenching her fist.

was an organization aimed at saving Spirits. They could not just sit back and watch this emergency unfold.

However, nothing came to Kotori's mind as she tried to concoct a specific method to solve the present situation. The usage of Fraxinus' weapons and CR-units might be able to suppress the runaway Spirits, but it would be no different from DEM's and AST's deplorable methods. Afterwards, unless they managed to deal with the power of the Spirits manually, the problem would be dragged out further.

However, it was impossible to seal the spiritual power of the Spirit, no matter how they utilized the capabilities of Realizer devices. If so, Kotori and the others had until now——

"Well…."

——Something was missing. Kotori frowned at the pain suddenly stabbing at her head.

It resembled a highly complex puzzle that was missing a vital component. Without that missing part, it would be very difficult to piece together.

"! Commander!"

As Kotori was thinking back and forth in a circle, she was snapped back into reality after one of the crew members called out to her.

In the deck of the observation post, the battle between the pair began when they both kicked off the ground ——no; rather, it was when they stomped the wall. The two of them had already been ignoring gravitational force the moment they started fighting.

One of them was wearing a dark Astral Dress and holding a single-edged sword ——the Inverse Spirit, Tohka.

The other person possessed flowing blonde hair, a Spirit who held onto a key-shaped halberd ——if one heeded Origami's words, then that person would appear to be Mukuro.

Both sides were running on the wall while scattering abnormal levels of spiritual power. With each exchange of their weapons, layers of glass coating the observation platform would be destroyed one after another by the aftermath of their spiritual power as sparkling fragments were scattered into the sky.

"...Anyway, we cannot just stand by and watch. At least the damage to the surroundings may be——"

Kotori was about to give instructions to the crew, but she was suddenly interrupted.

The sound indicating communication from the external line rang. "Communication... Where did it come from?"

"A general line——It's coming from Origami's mobile phone!"

"What was that...!? Hurry up and put us through!"

As Kotori issued the command, the sound of Origami's voice resounded from the speaker after a rustle of static noise.

"Kotori-chan…. It's Origami."

"Origami! What have you been doing!? Tohka and… who is that other

Spirit!?"

"Sorry, I'll explain later….! Time is running out! Quick, help me! Carrying on like this won't do. Can you stop those two's movements using Fraxinus' territory!?"

"That's... manageable, but it's impossible to completely suppress a Spirit of such strength. At best it'll only make them feel that their body has become heavier——"

As Kotori was speaking, another voice resonated from the speaker.

The voice did not come from Origami but sounded rather distinctively masculine instead.

"After that, leave it to me...!"

"What..."

Kotori widened her eyes in astonishment.

The voice of the unexpected man originated from Origami's phone, and yet Kotori was surprised by the tranquil feeling from hearing that voice.

"You, what are you talking about? Saying to leave it to you at the end——"

"There's no time to explain every detail. I have a way to stop them, so please believe me. Can you help me?"

"......"

That earnest voice made Kotori fall silent for a moment. But then.

"….Expand the territory to the area where Tohka and Mukuro are fighting! At the same time, deploy the to minimize the damage done to the surroundings!"

"Commander!?"

The crew members issued their astonishment. After all, even though it was also part of Origami's request, but for Kotori to actually listen to the words of a strange man...

Yet for some reason, even after Kotori had made the decision, there was a subtle feeling of it being positively appropriate. It was as though they had done this before; as if there had been several times where this boy had made the same request; like there had been a few occasions - with his unreasonableness.

Kotori pulled out her Chupa Chups and turned over her jacket before speaking.

"Enough, execute it immediately. This war belongs to us." "H-How is it, Itsuka-kun?"

Origami turned to face Shidou with an uneasy expression. He nodded his head in response and handed the cell phone back to her.

"Well, they're willing to help us." "Really? That's great..."

"Well... It's true that having Origami act as the intermediary was a big help." After Shidou said so, Origami shook her head in response with a fufu sound. "That's incorrect. Itsuka-kun was the one who conveyed those words."

"No, Kotori doesn't remember me right now."

Origami once again shook her head to refute his claim.

"Maybe that's not wrong, but surely it's not just because of that in this case. This time she naturally understood your words because you two are brother and sister.

"Is that so..."

Shidou scratched his face after giving a wry smile. He then took a deep breath and slapped his face to regain his concentration.

"But we're finally at the starting line. We must find a way to stop Mukuro and Tohka. Right now, we don't even know how Mukuro's relationship levels are, let alone if establishing the seal through a kiss with the memories still sealed will restore Tohka back to normal… Either way, sink or swim, we can only stake everything on a single chance."

Shidou clasped his fist and stared back at Origami.

"...Please, I can't stop the two of them by myself…Can you lend me a hand

too?"

"Itsuka-kun..."

Origami gave a slight smile, making a promise of her own.

"Of course, if I let Itsuka-kun go by himself, I'll certainly be at odds with myself

later on."

Origami exclaimed, as she extended her fingers and turned her body to continue.

"And besides… I'm really happy you'd want to rely on me. Being able to accompany Itsuka-kun——Girls don't get happy just by being protected, you know."

"Origami..."

As Shidou uttered her name, Origami gazed across his shoulder before directing a mischievous smile towards Shidou. Then, she fished out something which looked like a silver dog tag from her pocket and held it over her forehead as it chimed a ping of confirmation.

"Approval, Tobiichi Origami. —— deployed."

The next moment, a faint light surrounded Origami's body, and the elegant silhouette of metallic armor enclosed her frame.

CR-units were the technological culmination of the miraculous invention known as Realizers. It was the only instrument that enabled humans to fight on equal ground against the Spirits.

Not only was she suited up, but Origami had also overlaid the CR-unit

with a pure white Astral Dress which resembled a wedding gown.

"This is——"

"——Fufu. Have you fallen in love, Itsuka-kun?"

Despite Origami replying in a joking manner, her cheeks glowed with a reddish tint as if she was slightly embarrassed by her own words.

"Well, erm, I didn't mean it like that."

"Eh, haha…."

After Shidou had slowly loosened his mouth in reaction to the embarrassing retort, he quickly regained his composure by sharpening his gaze.

"——Let's go, Origami."

"Yeah... Itsuka-kun."

As both of them voiced so, they simultaneously stepped into the battlefield.

♢♢♢

——The streets echoed with the hustle and bustle of a turbulent siren.

While looking at the waves of the people rushing towards the refuge shelter, Natsumi wrinkled her brows in bewilderment.

"...The spacequake alarm? That means..."

"Could it be that... they're in trouble because of Tohka-san...?"

As if to answer Natsumi's statement, Yoshino responded in an anxious voice.

Although they had no inclination for thinking so, the possibility was very high. She nodded her head in consent.

After what had happened, Natsumi was now searching for Tohka and Origami, who had suddenly exhibited drastic changes in their respective personalities. Even though Kotori said to leave everything to her, not a single one of the Spirits could obediently stay silent and wait.

Despite them knowing virtually nothing about what happened to those two, it was obvious that the complication by no means comprised a usual, trivial matter.

The issue was not only centered around Origami acting more forthright and candid than usual. Instead, the main dilemma was Tohka, who, after collapsing from a violent headache, emitted a violent aura as she raised her head.

In spite of the resemblance to the time Nia had inverted, they were still unaware of the reason behind it. But that was——

"Yosshi! Nattsun!"

As she was lost in thought, Natsumi was brought back to reality when she heard someone call out to her.

Bestowing a special, signature nickname was a typical characteristic of Nia.

Looking in the direction of the voice, they saw Nia and the other Spirits, who had also been on the search for Tohka. It seems that they had all convened before coming here.

"What happened, have you found her?"

"No, but it looks like something happened on the other side of Tenguu Tower. We should go over there to check!"

Nia pointed in the opposite direction from which the flow of people emerged.

Natsumi and Yoshino, after exchanging glances, nodded their heads in agreement together.

♢♢♢

"Haaaaah!"

"Mere paltry gestures——!"

The key-shaped Angel and the Demon King sword clashed innumerable times.

Concurrently, the discharge of spiritual power behind every impact formed a compact explosion that dilated instantaneously, producing dazzling light and deafening shock waves which spread in all directions.

To boot, the key-shaped angel, , having changed its appearance from that of a staff to a halberd's, was creating numerous miniature doors at irregular intervals, launching attacks to target Tohka's blind spots.

For an ordinary person, it would be unfeasible to catch a glimpse of the flash sparked by a sword swing of such divine swiftness. No——even a Spirit should not be able to deflect the slash. In this regard, both sides were locked in a mutual stalemate. Seeing this, Tohka issued a declaration of faint praise towards her opponent.

Granted that could seal spirit power, it was only temporarily since the other side boasted the potential to open the seal. It seemed to resemble the sublime beauty of a closed flower bud rising into full bloom. Consolidated murderous intent and hostility were directed towards destroying the halberd.

The glass panes of the observation deck that Tohka and Mukuro used as footholds while they fought flew piece by piece in the aftermath of their battle.

Tohka turned around and jumped further to the top of the observation platform——moving towards the iron section of the tower.

"Dost thou desire to bereave Muku of company? To incite solitude in Muku?"

Mukuro issued a brief groan of lament as she prepared to commence another swift assault not a second later.

"Slay. Slay. Muku shall slay whosoever dares take Nushi-sama from her."

"Humph! Don't be all bark and no bite. Try to pierce me with that key, woman. If you can do it, just try."

"Thy remarks are undue...!"

In response to Tohka's taunt, Mukuro prepared to utilize .

As in concert with that action, Tohka felt a strange sensation dispersing through her body.

It was as if she had been swallowed by an invisible viscous liquid. The weight of her body felt heavier, and it became more and more tiresome to move her limbs.

"...What is this?"

For a moment, she thought it was the work of Mukuro——No. Mukuro also displayed the same sense of immobility. She directed her line of sight towards Tohka with an expression asking, "What did you just do?"

It would appear that neither of them was the culprit. Perhaps the ones behind this were the humans Shidou and Origami... or one of their collaborators.

However, such an annoyance would not change anything for Tohka. The enemy ought to be annihilated, nothing more.

"Take that!"

It seemed Mukuro had the same idea as Tohka. She kicked upwards to accelerate into the sky and used to dispatch an endless barrage of continuous, dense offensives.

Tohka inhaled a small breath and prepared to aim a piercing strike directed at

's handle to repel the assault.

"...Hmm?"

Possibly due to being faced with such offence and defense, Tohka slightly scowled.

There was no doubt that each of Mukuro's blows was besmeared with a power that could merit a fatal blow.

However, what was the best way to describe it. Tohka's intuition told her that Mukuro would not use this attack to decide the outcome of the battle there and then.

Any action taken by the other party should also be obstructed by the invisible force, and it was not like Mukuro had no intention to kill Tohka.

It was hard to say——but yes, it felt like she was merely paving the way for the finishing blow.

As Tohka was thinking, Mukuro made a discreet move. Using herculean effort to move , she took aim with the intentions to destroy with a piercing attack.

However, it had missed as a result of Tohka taking the precaution to, within the paper-thin difference in time, twist her body to avoid the attack.

But, at the very next moment.

"——."

After Tohka rotated her body to avoid , Mukuro used her angel to open a door behind Tohka.

"——Tsk."

For an instant, she thought an attack would burst from that door——yet that was not the case.

The door began to breathe as it sucked in the surrounding air.

Tohka, who was standing near the steel tower, was thrown into the sky. Maybe the other side of the 'door' was connected to a space with a large pressure difference.

Although Mukuro predicted that this would not be enough to suck Tohka in whole, it presented nothing more than a chance to strike at a vulnerable opening——.

"!"

Hearing Mukuro shout interrupted Tohka's thought process.

The huge door that had opened in front of Tohka must have been at least a hundred meters in diameter. It sucked in all the nearby lumps of iron, stone, wood, along with any other polymers composing the structure.

"Chi——"

Perhaps the gravitational pull was strong enough to even attract a massive building. Tohka fixed her posture holding and directed her blade towards the edifice.

In a single slash, the sword severed the building precisely like a line. The two halves avoided Tohka and fell to the ground.

But at that moment.

"——!"

Just after noticing the door between the large sliced buildings that Tohka had recently precipitated, a key-shaped halberd stabbed outwards from within it.

"————"

Having already prepared herself for another sword swinging stance, even if she had turned around, it would be too late.

As the spear end of was about to impale Tohka, it pierced through a wedge of the building that was falling.

Then—— "What...?"

Tohka frowned instinctively.

The huge constructions surrounding Mukuro, as well as Tohka's Astral Dress, were instantly annihilated.

Even though it had been torn apart, it was not engulfed by the door - it just vanished into thin air from the spot.

Nevertheless, time would not wait for their consideration. As the door continued to enlarge, from there, Mukuro continued to launch a relentless raid of attacks using .

"Hah!"

"These useless acts of yours…!"

Tohka defended against 's onslaught while moving out of the way by riding the momentum.

After landing on the ground, she summoned again the Astral Dress which had been entirely erased moments ago.

That being said, the Astral Dress had yet to be completely restored to its original state. Even for a Spirit, creating an Astral Dress that served as an absolute fortress required a considerable amount of spirit power. The fact that the Astral Dress was lost without lowering the input power meant that the aggregate amount had been shaven down.

"...…"

As Tohka was monitoring Mukuro's movements without hesitation, she felt the remnants of spiritual particles in her surroundings.

"The spirit power which constituted my Astral Dress remains in the air——this is not utter destruction. It seems to me that key can disintegrate molecules and spirit particles. I see, so this is your trump card."

"...…"

Mukuro did not answer but matched her field of vision to Tohka on the ground.

In response, Tohka postured herself to use in a perfunctory manner.

In front of her stood a worthy opponent.

Even though her emotions were coated with murderous notions, Tohka could still calmly look into her opponent's gap——That's right, if one must say, it was nerve racking because she was so calm.

"——Humph. You make up a decent fighter, even with your childish face."

After giving a thin smirk, Tohka turned to point towards her cutely worthy rival.

However, just before the two were about to cross weapons again.

"Wait, you guys!"

"Please, you two, calm down!"

Shidou and Origami appeared between them.

Tohka pouted her lips in displeasure as she re-gripped her grasp on

's hilt.

"Have you come to block my way? ...Well, whatever. I already intended to defeat everyone!"

Tohka gave a loud roar as she swung down , the jet-black sword drawing forth a crescent moon-shaped arc towards Mukuro and the two people who had come to interfere.

However, Origami, who was wearing both a metallic armor and her limited Astral Dress, massed the black spirit power to the tip of her spear before dissipating Tohka's attack.

"...What?"

Tohka narrowed her eyes at the unexpected phenomenon.

She was not entirely surprised that Origami could deflect that blow. Right now, Tohka's movements were restricted by some mysterious power; so naturally, it was not a serious release of her sword swing. Also, if Origami had been using the power of a Spirit, it would not have been strange for her to be able to block the attack.

However, it was evident that Origami was carrying the same type of fragrance as Tohka——in other words, the so-called inverse spirit power.

The sensation Origami exuded was similar to the spirit power enveloping Tohka right now.

Perhaps the tip of the spear could accumulate the spiritual pressure drifting around the vicinity. After all, the high output should be reasonable owing to the abundant quantity of spirit particles composing her Astral Dress, which had been broken down by Mukuro.

"Hmm... this one's good, that too——"

Tohka honed her range of sight as she heaved over her head. Then, she kicked off the ground to leap into the air.

"——You can keep me entertained!"

"...! She's coming! Itsuka-kun, I'll leave you to deal with Mukuro-chan!"

As Origami shouted, the dark spirit power surrounding the tip of her spear formed a barrier to protect Shidou from Tohka's attacks.

Tohka, who was adorned in a black Astral Dress, and Origami, who donned a white one, both flew into high altitude as they exchanged mutually intertwining blows.

Looking at the scene from the ground, Mukuro grumbled something in a subtle voice.

"Slay... Slay. Aught, who would pilfer Nushi-sama, are adversaries.

Muku… Muku disrelishes… loneliness." "Mukuro!"

"...!"

After suddenly hearing her name being mentioned, Mukuro turned her eyes to the direction of the voice.

"——Nushi-sama."

Exactly. In front of Mukuro was none other than Itsuka Shidou.

"O-Oh... Nushi-sama, Nushi-sama. Stay assured, for Muku will return that wench to naught. Thereafter——"

"Mukuro!"

In order to interrupt her, Shidou grabbed Mukuro by her shoulders and once again shouted her name out. Mukuro couldn't help but be afraid after seeing such a desperate look.

"What be the matter, Nushi-sama? Entrust everything to Mukuro."

"That's not right... It shouldn't be like that, Mukuro...! Stop this. I don't want Tohka to disappear or Origami to forget about me. I'd really hate that...! Both of them are..... no, everyone is precious to me!"

"..."

Listening to Shidou's words, Mukuro's body convulsed as though she had just choked on her breath.

However, Shidou resumed without noticing Mukuro's condition.

"Why... Why? Please tell me, Mukuro. Why are you trying to eliminate

everyone?"

Shidou remarked at the end of his tether as he pleaded. Mukuro replied with a trembling voice from her throat. "——Why."

"Huh?"

"Why doth Nushi-sama speak such vocables? Loves... Nushi-sama Muku not? Muku loves Nushi-sama withal. Doth that not suffice? Yet wherefore!? Wherefore!!"

Mukuro paid no attention to the tears brewing in her eyes.

"Muku loathes this, Muku wishes not to be alone...! Be it Nushi-sama or whosoever——"

"——Tohka-san! Origami-san!"

At that point, as if to interrupt Mukuro, a voice appeared from an unknown location.

"W-Why are those two fighting each other...!" "Kya——! What a disaster——!"

"——"

Six girls appeared unexpectedly.

They were the Spirits whose memories should have been locked by Mukuro using her angel. With a confused face, they all looked up to the sky, watching the fight between Tohka and Origami.

"What——"

Looking at those girls, Mukuro felt as if her heart had just tightly contracted.

"All of you forbye... Ye have come to snatch Nushi-sama away from Muku? Unforgivable. Unforgivable! No longer——"

Her head was spinning around, while a nauseous feeling spread through her body.

Mukuro placed her two hands on as she turned its tip—— "—— !"

Towards the ground——no, she inserted the key towards the Earth and turned it around.

At that moment, with that location as the epicenter, vigorous earthquakes started to propagate through the periphery.

For the people who were standing there, it gave the impression of being near an industry-scale drilling machine.

It was as if the Earth had transformed into some sort of planetary creature that was pulsating.

The tremors began to encompass the nearby surroundings.

"…Tsk!? Wa, what!?

"...W-What's going on!?" "Predicament. Is this an earthquake?"

Shidou and the Spirits were stunned by the loud noise ringing their eardrums. Mukuro gave out a gentle smile as she stroked Shidou's face with her hand. "No longer... need thou worry. With this... none shall pester us."

"Mukuro...? What did you just do?"

"——To this Earth, hath been cast. Howbeit, a few ticks of the clock seem to be of necessity in the wake of its vastness, albeit in ultimatum, this celestial body shall cease all motion."

"What?"

Shidou was momentarily stunned as he stumbled on his words. However, Mukuro did not appear to notice Shidou's expression, her smile becoming more unnerving as she continued to speak.

"Thus, all beings which cumber will perish. Nushi-sama shall with Muku bear company in the cosmos for aye. Hehe... What eagerness."

"What are... you saying——"

The color of Shidou's facial expression was that of complete bafflement.

Mukuro did not worry about his facial expression——That's right, there was one more enemy that she could not let anyone else defeat.

"Hey, Mukuro! Wait!"

While listening to Shidou's voice from her back, Mukuro looked up at the black shadow in the sky and kicked the trembling ground.

"Kya——! It's an earthquake——! I'm scared——! Natsumi shield activated—

—!"

"Aren't you still able to brief the situation leisurely...!"

Natsumi shoved away Miku, who was using the seismic episode as an excuse to hug her... Needless to say, the differences in physical and mental strength rendered any resistance useless.

However, now was not the time to be concerned with that event. After all, Origami and Tohka were fighting an intense battle in the sky; the spacequake alarm was ringing ceaselessly; and there was the mysterious trembling of the ground. They didn't even know what to do first in this situation.

"W-What on Earth should be done...?"

"Well….although I'm not really on top of things, right now it's not okay to not stop Orimin from fighting with Toka.

"Agreement. If this continues, it will be noticed by AST and DEM——"

"——Everybody!"

At this time, they all suddenly heard a distant voice. The Spirits looked in the direction of that voice.

"...Eh?"

After looking at the figure of the person who stood there, they all stared unexpectedly.

It was a natural reaction. After all, it was the strange boy who had cried out yesterday.

"You…you're the person from yesterday...?"

"...Eh, to be able to stalk us even when the spacequake alarm is going off, some people would be impressed. Ah, but I won't feel touched by it."

Natsumi responded with her eyes half-closed as a boy was running towards the group in a panicked state.

Sensing the alarm in everyone's eyes, the boy lowered his head.

"Everybody ... please! Please lend me your power!" "...Ha? Eh, what...?"

At the sudden request, the Spirits all formed puzzled expressions on their faces.

"Er... What happened?"

Despite bearing a confused look, Yoshino still felt the need to say that. Truly, she had to be a goddess with a heart filled with affection in order to be this gentle towards a complete stranger.

Then, the boy lifted his face.

"Mukuro——that Spirit who turned her key to the earth. If this goes on, it'll

become a huge disaster! Please… everyone… lend me your strength!"

Just like this, the young man continued his desperate plea.

But... Natsumi frowned in response. That's right. First of all, the meaning of that boy's words was still unknown. Apparently, he knew well about the Spirits, yet this fact merely made him sound even more suspicious.

——However.

"...I understand if you can't believe in me."

After a little hesitation, Yoshino nodded her head. Natsumi opened her eyes and glanced at that direction.

"Y-Yoshino? Wouldn't it be better to approach with more consideration? I guess it's too suspicious like this..."

"Yes... but he doesn't look like a bad person. Though I'm not sure how to put it, I, uh—— want to be able to become this person's strength."

Yoshino's eyes brimmed with firm determination as she shook her head. Afterwards, the other Spirits started to agree one by one too.

"Kaka, so be it. At least he seems to apprehend the minimal amount of

manners."

"Approval. For some reason, I presume this has happened before."

"Mu... Well, if all of you say that... A boy is a boy, but when you trim it a bit you'd look pretty cute."

"Ah——didn't it work out in the end? Something like this really gets your blood fired up."

"Everyone..."

The young boy wiped his faintly moist eyes.

Natsumi seemed to feel slightly embarrassed, taking in a deep breath.

"...What. This makes me seem like the only bad guy here? I understand; I'll follow along as well——What are we supposed to do first?"

As Natsumi finished, a jubilant expression surfaced on the face of the boy—

—then, suddenly his body stopped moving.

"Well, that's——"

Apparently, he had not even considered what to do first. Natsumi once again breathed out a sigh.

At that moment…

"——Really, what are you guys doing."

Although they couldn't verify the source, they had all heard Kotori's voice.

"! Kotori-san!?" "Eh, from where?"

"I'm transmitting my voice through 's Territory system. ——Just like that boy said, the ground is being corroded by spirit power. Although we're unaware of what will happen to the Earth, we can't just leave it alone.

——For now, we've designated six different locations as the starting points with the . If you start sending your Reiryoku to those points, we may be able to delay the corrosion of the ground for a while."

"Huh, I see. That's incredible, Kotori. Be my family."

"That won't be necessary. ——It will only be able to delay it for a while. Unless we do something about the Spirit and Angel who caused this, the problem will still persist. ——Can we really can leave it to you, Itsuka Shidou?"

After Kotori ended her question, the young man nodded his head in confirmation.

"Ah... Thank you so much, everyone, I'm really grateful."

After finishing, the boy turned his back to everyone and began to head out. Seeing this action, Natsumi asked another question.

"...Where are you going?"

Without looking back, the boy answered.

"To that place, where a child is waiting for my hand."

♢♢♢

On the ground that continued to vibrate slightly.

"Nushi-sama——Muku shall concede not."

Mukuro sharpened her range of sight as she gazed at Origami and Tohka exchanging mutual blows in the sky.

Towards Tohka, who was currently preoccupied with fighting Origami, it was certainly possible for Mukuro to take advantage of the situation to launch a successful attack from behind.

"——!"

As Mukuro shouted, she used her hands to turn . At that moment, a 'door' appeared, wherein the front tip of could barely fit.

Of course, the other side of the door was connected to a blind spot of Tohka's. ——There, would pierce and turn. In that case, everything would be over. , 's secret ability to ensure the total decomposition of any material matter. In front of this unparalleled power, all things in this world would return to nothingness. At this point, even Tohka should be no exception.

"...!"

After Mukuro spotted the timing where Origami and Tohka were distracted by their clash, a small key-shaped angel would protrude out into the space from a door.

However——

"Don't do it! Mukuro!"

Just as was about to pierce through the door, Shidou stood up and spread out his hands in front of Mukuro.

"——!?"

Due to the unexpected action from Shidou, Mukuro gawked blankly with her eyes as her body began to tremble.

But it was too late. Through the reflexes of her wrist, slightly deviated from its target as it pierced through Shidou's shoulder.

"Kuh...!?"

Shidou's face distorted with pain. In response, Mukuro quickly used her arms to stop the influx of power being unleashed by .

But.

"————Eh?"

At the next instant, as if hit by a strange sensation, Mukuro let out a stunned voice.

By piercing Shidou with the long halberd, phantom-like images began to manifest, with feelings of undiluted anger that flowed through. No, to be more precise, there was also something flowing from Mukuro's side.

Although they didn't know what it was in the end; however, it seemed as if the feelings between Mukuro and Shidou were being intermingled. It was like the feeling of shaking two different liquids within a bottle together.

Ah——but it wasn't the first time she encountered this feeling. Exactly. At that time in outer space, the same feelings brewed when Shidou had used his pseudo to pierce her.

"——"

——That's right, at that time.

——

That cold winter day.

In the face of my own frustration, certain existence appeared.

It bore semblance to someone who was fully submerged in water, or a strange figure enshrouded in mosaics.

And that someone had given me something resembling a gemstone with a brilliant golden hue.

From that moment onwards, I, ——Hoshimiya Mukuro, became a Spirit. However, I felt neither doubts nor fears.

No, rather it would be more appropriate to say that I felt an even greater feeling of joy.

I had received , a key-shaped angel which could close any object—

—even invisible things such as human memories could be locked.

Using this power, I could certainly make sister, father, and mother love only me.

So, I immediately, and gladly, used this power. Opening a door in space, I utilized to close the memories of my family from every acquaintance, or nearly anyone that recognized my sister and parents for that matter.

——However, in the end, things did not go as I had planned.

After coming back home, the reactions of my family were filled with utter confusion. The unusual situation of having no one remember them left a sense of overwhelming bewilderment; nobody was concerned about Mukuro.

I believed that if all the surrounding people were to forget about them, they would all love me again.

Yet, the backlash from my family after discovering that I had been the cause of the situation was far from love or affection.

Astonishment and anger; dismay and agitation; and also——rejection.

Father, Mother, and sister were all afraid of how I obtained such unfathomable power and thereafter alienated me.

Not much was to be reminisced with regard to what they had said subsequently. In spite of being able to recall the scene as vividly as it had occurred, only fragmented words came and disappeared.

"Monster", "Ah, what did you do", "Don't kill", "Get out", "You're——not our family".

Evidently, perhaps the brain had judged that my heart would be unable to bear the burden of all those memories, so they were specifically frayed and tattered in this manner.

Even so, I could clearly remember the painful knot in my chest at that time.

Uncomfortable, sad, painful, and lonely, ——these feelings spun around constantly in my head. And so, I went to Father, Mother, and sister, using

to lock each and every single memory of myself.

——Because it seemed as though something would have happened if those words had plagued me any longer.

And thus, I was alone again.

Though it was by no means the same——I returned to loneliness after having experienced the warmth of a family. It cruelly mirrored starving a man who had known satisfaction all too well.

In retrospect, I likely possessed no qualifications to ever love something in the first place.

Being born without love, I failed to notice how its shape had contorted. If you love, you must also be loved.

If you love, you must look within solely yourself. Therefore, Mukuro closed the lock.

To my memories. To my heart.

In order not to recall the warmth of a family after having felt it once.

——In order to never love something again.

——

"Ah——"

In front of the door opened in space, Shidou let out a small voice that sounded unusual of someone who just had stabbed into his shoulder.

Remarkably, it was not that painful. Rather, via , the memory of a girl came flowing into him.

It was the dream that Shidou had been watching for the last few days.

And——it was probably the memories that Mukuro had sealed.

Thinking about it, Shidou had only dreamed that after he had used his pseudo

to open the lock on Mukuro's heart in outer space.

Although he was oblivious to its specific principles, but perhaps at that time, the seal locking Mukuro's memories collapsed, allowing her recollections to be relayed through and into Shidou.

Then, again by means of , the memory was shared between the two of them.

"Mukuro... you're, no, you too are——"

Shidou imparted a small voice while trembling and reaching out to Mukuro. But at the next moment.

"Ah, gah...!?"

Shidou now perceived a severe pain in the region where had struck. From his shoulder down to his wrist, everything had snapped and ricocheted like a bullet.

"Ou... ugh, gaaaaaaaah??"

As a result of the pain from the shock, Shidou gave out a scream as if his throat had been crushed.

It was a completely distinct feeling in comparison to having his hand cut off. His shoulder disappeared as though denying it had ever been there. What remained of his wrist fell to the ground over a large pool of blood.

"Ga ... ah, aaaaaah!"

Shidou reflexively used the Angel of music, . He employed the spirit power in his voice to increase his resilience in order to withstand the bleeding and torment.

At the same time, Shidou called on , even though it was at a pitiable level, to close the wound…. Had Mukuro used to seal away his ability to use , he would have been incapable of doing anything. Fortunately, it seemed that only 's ability to transform into had been closed.

Of course, despite giving the impression of water on rocks, it only had a minor effect——at least it prevented him from going crazy owing to the anguish or losing consciousness.

Even with 's healing flames generating smoke on the wound, it was uncertain if it could cure a trauma of such magnitude. It would take more time if possible, as even now the effect still hadn't kicked in.

Shidou's face was covered in sweat as he looked towards Mukuro.

"Mu-… -kuro——"

"Ah… A-Ah——Nushi-sama, nay...! Muku, Muku wished not to kill Nushi-

sama..."

But looking at the sky with empty eyes, Mukuro's body began to quiver with fear. She dropped down from her arms and started talking in incoherent words.

"Nay... Forsake Muku not... a-a-a-ah, Nushi-sama, Ane-sama... Muku, Muku…............. "

Like a dream, memories and reality began to jumble in her mind. Mukuro held her head tightly in confusion.

The next moment, tears dripped from Mukuro's eyes. A torrent of spirit power of a muddy color began to emanate from her body.

"Ugh—— a-aaaaaaaaaargh!——"

"This is..."

Shidou squeezed out a hoarse voice.

He was no stranger to this phenomenon. ——Inversion.

The fact that she had, by her own hand, caused a mortal injury to Shidou, and——simultaneously recovered the memories that she herself closed in her mind.

Certainly, these factors were enough for engulfing Mukuro's heart in an abyss of despair.

Crimson cracks appeared on the elegant and valiant Spirit, taking on a color that embodied chaos itself. The flowing tears transformed into pitch black

darkness, and , which had fallen to the ground, dissipated into dust. Then, a large demonic key began to appear behind Mukuro.

"No, please... Stop, Mukuro!"

If this subsisted any further, Mukuro would really invert. Shidou slowly stepped forward with staggering feet.

However, Mukuro's body lay at the very center of a potent vortex of spiritual power that stopped Shidou's advancement and pushed him back in retaliation.

"Guh——!"

In his current condition, it was arduously difficult to avoid the attack. Somehow, he managed to endure the blow by focusing all of his strength to his feet.

At the next moment, a tremendous slash fell from above, dissipating the spirit power in front of Shidou like foggy mist.

"Eh——?"

Shidou started blankly at the sight. At first, he thought it was assistance provided by ——but that was wrong. This was from .

"Humph."

While in thought, Shidou heard a voice coming from the sky.

"Don't misunderstand. As to why I humiliated myself for a bastard like you, such an easy death would be unsuitable even for the likes of you."

Tohka gave an annoyed expression before once more facing against Origami in the sky.

"Tohka..."

Shidou whispered for a moment before turning to face Mukuro.

Tohka's words likely didn't contain any especial implications. But it was an indisputable fact that her blow had paved the way for him. Shidou couldn't save her by himself, so he thanked Tohka for providing him with the

opportunity to reach Mukuro. While taking small footsteps, he reached out his remaining hand to hold Mukuro.

His body could muster only a bit more power. It would be more accurate to say that he was leaning forward rather than embracing her. ——Yet that didn't matter. Shidou gathered the strength in his throat to say something.

"Mukuro! Mukuro! Come back! No, you can't go over there!'

Shidou was using the last ounce of strength in his body to talk to Mukuro.

——Shidou had not understood it before.

The reason for why Mukuro wanted to exclude everyone and monopolize Shidou.

As a matter of fact, jealousy, alongside the desire to keep someone for oneself, was a feeling which everybody had. However, in Mukuro's case, the extent was way beyond the level of ordinary.

Nonetheless, speaking of the present.

Through Mukuro's memories that were shared by , Shidou now understood.

Because——

"Mukuro... you're——me."

Shidou continued to talk to Mukuro, who was enveloped in darkness.

Yes, Mukuro and Shidou were extremely similar to each other. That's why Shidou had first thought that the dream of Mukuro's past was rather of his own past.

In the past, Shidou had been abandoned by his mother and had become caught in loneliness.

Yet, when he was adopted by the Itsuka family——father, mother, a little sister——for the first time, he also understood the warmth of a family.

Therefore, he could comprehend.

"Mukuro... You were actually worried inside. You were in distress, yet you

didn't know what to do, right?"

Mukuro's shoulders began to convulse after she heard Shidou's hoarse voice. Precisely, Mukuro felt uneasy.

Because in the beginning of her memory, the existence named 'love' was absent.

One day, all of a sudden, she was given a warm, tender feeling that was comfortable and dazzling while not knowing how to cling onto it.

It truly sent forth the sensation of a dreamlike, ethereal existence, instigating, unbeknown to them, the fear of losing everything when the dreamer themselves awakens into reality.

Even when immersed in happiness, there would always linger a trace of anxiety within oneself.

So, if one's family were to consort with someone other than oneself, one would learn that they belonged to an unfamiliar world. The feeling of one's heart being tightened would undoubtedly be enkindled.

After all, there was the thought that he was a human grafted into their lives; there might be other things that those people deem more valuable.

Although it wasn't as excessive as Mukuro's instance, this sentiment also existed within Shidou's own heart.

"But, Mukuro... Don't worry about it."

With blurred vision, Shidou continued to speak as he stroked Mukuro's head.

"You don't need to worry about it. Father, mother, brothers and sisters... no matter how far apart, you'll always be linked together. Because——that's what family is."

Yes, he was taught that by Kotori and his parents.

But if Shidou was given the same power as Mukuro, he wouldn't know what he might have done either.

"…........ uh"

As a result of what Shidou said, Mukuro exhaled a small breath.

"But... Muku… to Muku… hath…" "...You'll still have me!"

To answer Mukuro's faint consciousness, which seemed like it could possibly disappear at any moment, Shidou raised his voice.

"I will be… your family, so you don't have to worry anymore. No matter what,

I'll never forget you. No matter what you do, I'll never hate you…"

Despite coughing fiercely and blood spewing from his mouth, Shidou did not care and continued to speak.

"Ah... that's not all. Mukuro, you too… Promise me… There's no point in one-way love. ——Because we're… a family."

"...! Nushi-sama, Muku——"

Muku responded with her lips slightly trembling.

Then, at that moment the tears, which were murky like sludge, returned to its original transparency.

However, it wasn't over yet. The spirit power surrounding them was increasing in momentum.

It was now the critical juncture to determine whether Mukuro could entirely return to their side.

"Mukuro——"

He didn't know if Mukuro had accepted his words. However, there was no time left to waste. Shidou used the final shred of his energy to lift his face——

"Wha..." "————"

His lips touched Mukuro's for an ephemeral moment.

This was a blood-soaked kiss with an odor like metallic iron. After giving a small prayer, Shidou closed his eyes tightly.

It was a sensation that he had experienced many times before. By establishing the seal, spirit power flowed from Mukuro's body and into Shidou.

Simultaneously, the Astral Dress that Mukuro was wearing and the key- shaped Demon King lost its radiance, melting away and fading into the air.

"...Mukuro!"

"Ah... um..."

Having become stark naked, Mukuro abruptly leant over.

However, to Shidou, who had well exceeded his limit, being leant against by Mukuro broke his posture as he collapsed backwards.

"Gua-yah...!?"

He stroked the back of his head strongly, shouting a miserable scream.

But if one were to ask for the root of the shriek, it would mainly be due to the shock from his previous wounds.

Despite using a combination of abilities from , , as well as

, for the emergency treatment, under normal circumstances, this would have unquestionably been a fatal injury——Even death would not prove to be unlikely from such affliction. Rather, it should be said that his reaction towards being collapsed upon was commendable, given his condition.

"...."

Perhaps tired from the crying or having exhausted all of her stamina, Mukuro sent a yawn yearning for sleep, while her chest was still soaked with Shidou's blood.

Shidou heaved a deep sigh of relief.

"Mukuro… thank you for believing in me..."

Shidou loosened his neck as he caressed Mukuro's head while looking up towards the heavens.

...But how was he to describe it. Shidou then discerned a kind of unspeakably bad feeling.

Obviously, he had just completed a super difficult task, but it was the type of sensation of forgetting something very important.

At that time, as if to verify what Shidou was thinking, something from the sky approached his view at a tremendous speed.

"What...!?"

Shidou opened his eyes wide in astonishment.

As the flying object approached them, it quickly decelerated to land beside

Shidou's head quietly.

A dark skirt fluttered in the wind and embraced Shidou's sight. That's right. It appeared there.

"——Pfft. I thought there was something to see, but in the end, this is the result, woman."

The voice came from the Inverse Spirit Tohka, who should have been in the middle of an aerial battle against Origami.

"To… hka….!"

Shidou held his breath, as he moved to protect Mukuro, who was sleeping on his chest.

"...Thank you. Because… of you… I could… stop… Mukuro..."

"Hmm, I don't care about that. Anyhow, I can now kill two birds with one

stone."

Shidou found himself unable to look back as Tohka stared at them with murderous eyes.

Mukuro's spirit power was sealed and she had already lost consciousness. Likewise, it would be a mistake to assume that Shidou was in any reasonable condition to fight. Both were powerless against Tohka.

"Uck——Are you alright!?"

Falling a few seconds behind Tohka, Origami arrived at a position slightly away.

However, both her limited Astral Dress and CR-Unit displayed signs of damage. It seemed to be a struggle for even Origami to fight against the inverted Tohka.

"...…"

Tohka glanced at Origami for a second before returning her attention to Shidou and Mukuro.

Shidou could detect himself exuding cold sweat.

That's right; the supposed assistance earlier was merely one of Tohka's fleeting whims. Only another could save them now. If she felt like it, Shidou and even Mukuro, as well as Origami, would all be killed.

"Kuh..."

Shidou placed Mukuro's body on the ground as gently as possible, before fighting against the nauseating pain to stand up.

The state of his body was beyond being considered as just bad. If one had to choose between a human and a zombie, he more resembled the latter right now.

However, in order to return Tohka to normal, Shidou summoned his strength and slowly raised his body, with one knee still on the ground.

"Guh... ah, ugh..." "——Hmph."

Tohka lowered her eyes condescendingly towards Shidou as she looked on with a cold stare. Then, she forcibly grabbed him by the collar.

"Guaa...!?"

"Itsuka-kun!"

Origami hollered a scream as she prepared to attack Tohka.

However, as Tohka glowered at her, Origami stopped in place without warning. At that distance, if Origami acted rashly before Tohka, Shidou's head would be the first to come off flying.

"...….."

As Tohka looked on towards Shidou, whose countenance exhibited a grimace of suffering, she slowly raised Shidou's body upwards.

Then, she looked at Mukuro, who was sleeping on the floor, before stating something in a cold voice.

"——You've turned such a competent warrior into a child." "Guh..."

Shidou saw that there was a glint of ire in her eyes that was staring daggers at him.

However, the next moment, Tohka merely gave a heavy glance and uttered something with an air of loneliness.

"...My interest is gone." "Huh——"

After hearing the tone of inverse Tohka's voice, Shidou could not refrain from being flabbergasted in response.

However, that surprise was then surpassed by an even greater bafflement.

Tohka, while clutching Shidou's collar, pressed her lips onto Shidou's without any hesitation.

"Uhmmm…!?" "Kya——!?"

Shidou and Origami's voices overlapped as they both issued exclamations of surprise at the same time.

Yet, Tohka did not show any sign of embarrassment as she let go of the hand gripping Shidou's collar.

"….…Ow!"

As Shidou once again fell to the ground on his backside, the subsequent vibrations spread the pain all throughout his body.

Despite his face twisting in pain, Shidou did not take his eyes away from Tohka.

——Tohka's jet-black Astral Dress disintegrated into light particles that were swept with the wind.

Tohka, who looked as cold as ever, had a mysterious look in her eyes as she looked towards Shidou before muttering something.

"Don't let me——" "Huh...?"

"Don't let Tohka feel sad."

She suddenly lost consciousness and fell down onto the ground.

"T-Tohka!?"

Shidou panicked as he saw Tohka's face as she collapsed.

"Muu...…"

It was a very steady and gentle sleeping face.

Her facial features had changed back into her everyday expression. Sensing that the tension had left the atmosphere, Shidou breathed out a sigh of relief before falling down limp on his heads and knees.

"Itsuka-kun, are you okay!?"

Having been observing what had transpired, Origami quickly approached him. Shidou gave a wry smile as he waved feebly.

"Finally... ah, no, as expected, things have finally settled."

"Yes, that's, ah! Such heavy injuries... We have to get you treated in the medical Realizer as soon as possible!"

"Ah… that's true. Have Kotori and the others regained their memories? We can't leave Mukuro and Tohka naked here. should come quickly from above..."

Then.

Shidou suddenly stopped speaking.

No, it was semi-mandatory to stop halfway.

——Mukuro had unexpectedly pressed her lips against his on the spot.

"Pffuu… Mu-Mukuro!?"

"...Hehe, in ill-caution lies man's greatest foe, Nushi-sama."

As Shidou's face was flushed red with embarrassment, Mukuro staggered as she showed a bold smile.

"Wh-What are you saying..."

"Had thou not plant'd a kiss on Tohka's lips just afore?" "Ehh..."

Listening to what Mukuro had said, Shidou slightly twitched his eyebrows.

He had even thought that Mukuro would have accepted his words. Contrary to what he expected, she had still not given up on monopolizing Shidou——

Mukuro, who had likely read his thoughts, gave out a slight giggle.

"Rest contented. Thou needn't... worry more. Whatsoever Shidou aspires, Muku shan't be at unease. All in all... we are a family."

As she said that, her face had a reddish hue to it as though she were a bit shy.

Seeing this, Shidou gave out a short sigh as he loosened his cheeks.

"Mukuro..." "However."

Mukuro interrupted Shidou by placing her finger on his lips. "Such skin ship is verily comely, aye? We are family, if aught." She replied with a mischievous smile.

"...U-Um…"

"...Family is… that type of family…"

Shidou started to worry over whether he could take responsibility for his pronouncements.