Disclaimer: I don't own demon slayer or guyver.
3rd(p.o.v.)
A lone figure stood on what seems to be the edge of a spacecraft, looking up towards the stars. The figure, who looked to be a young man in some kind of armor. It was a bluish gray color that gleamed even in the night sky, it had two orbs on top of his head, with a fin in the center of the orbs, in the center of his head, there was a more smaller orb, with an even smaller green one right above it, the eyes were covered. Going lower on the face, there were two tiny balls right in the center of where mouth is supposed to be, on either side of balls, there are protrusions sticking out, which let out some steam. On his waist, there was one last orb in the center. There were short blades on his elbows. And his feet showed two-toed footwear.
The figure, who was also 174 cm (5'8") tall, let out a heavy sigh, lowered his gaze slightly to the left, and spoke in a slightly distorted voice,
Mysterious figure: Unit, do you think that there was a better way. A way that didn't involve our friends dying. A way to get stronger faster without all of those sacrifices.
Unit: Host did his best, he did everything he could have. It was host Sho Fukamachi's friends choice to do what they did to give you a fighting chance.
The figure, now named Sho Fukamachi sighed heavily.
Sho: But why? Why did they need to sacrifice themselves for, and all for nothing at that. Why couldn't Agito have been the one to have survived. Maybe he would've prevented all the destruction that I had caused, maybe all our friends would still be alive right now.
Sho had gestured to the barren waste land, with destruction so vast, it didn't seem to have an end.


This was caused by the fight between Sho, a being called Archanfel,

and beings known as the advents.

It was a long and perilous battle, ravaging worlds, even outright destroying them. But Sho, with his gigantic exceed form, managed to win. But it came at a cost. There were a numerous and countless number of casualties, in which all his loved ones died.
Sho: I wasn't strong enough to prevent their deaths. Now, I'm the only one who's still standing. What can I do to stop this pain, unit. Because it's almost unbearable, if you weren't here.
The voice known as unit answered in an almost robotic tone,
Unit: You did everything you could have to get the best possible results host, there was nothing else that you could have done to prevent what happened, it was not your fault.
Sho: I know, it just feels like it is. Maybe there was something else I could have done, maybe gotten more stronger.
Unit: You did your best, host. I wish I could have helped you more than I ever could, but I can't. Sorry for letting you down. Sorry for not helping you enough, I'm just, so sorry.
The way Unit said it, almost sounds like they were a real human, with with real human emotions. It made Sho feel bad for making Unit feel bad.
Sho: It's not your fault Unit, I was just immature and scared the first time you attached yourself to me. I didn't know what was going on, so I tried to reject the nightmare that had started, which led to me ignoring you because I couldn't accept what was happening. So, I'm sorry, for not accepting you until now.
Sho let out a heavy sigh, before asking a rather obvious question that he had no answer to,
Sho: Well, what do we do now, because I don't have any idea.
Unit stayed quiet for a moment, thinking about how to respond to the question. Then it answered,
Unit: Why don't I revert back to my default state with you in me. Then we'll use the new wormhole feature that we unlocked before the final battle. Then, we'll go from there.
Sho thought about it for a moment, before asking,
Sho: Will I die?
The control metal glowed briefly, before Unit answered,
Unit: We will be combined into one being, one entity. One soul with two minds. Although, unless someone else comes in contact with the unit, we are able to turn back as we are right now if you wish. However, if someone were to come into contact with the unit, all previous host DNA and genetic material will be gone, to be replaced with a new host own. You however, will basically become a spectator and a second inner voice to the new host.
Unit finished explaining what would happen if they go through with it's plan. Now, it waited for it's hos- no, it's best friend, to give an answer. Sho thought about it for a few minutes, before deciding,
Sho: Let's do it, anything is better than this desolate waste land.
He gestured to the destruction in front of him, while also agreeing to go through with the plan.
Unit: Then I will begin the process right away.
Unit thought for a bit, before adding,
Unit: It has been an honor to be able to work with you through the many years we've been together. Thank you, Sho Fukamachi.
Sho, even though he his helmet and mask on, had tears in his eyes as he said,
Sho: No, thank you for your patience in putting up with a brat like me. It has been a pleasure to have worked with for so long. So thank you. And Unit, good bye.
After he said his piece, everything went black and his eye covering turned red, signaling that Unit had taken control over his body.
Unit: Good bye, Sho. Until we meet again.
It whispered in a soft voice. It then activated their new wormhole ability, shrinking and reverting back to it's original state and fall to the floor, before getting sucked into the wormhole.
What they didn't know, was that because it was a new feature, they didn't know everything about it. They only knew about the highlighted version of it, not what it can actually do. And, because of that, it began to absorb everything it could after their departure, getting bigger and bigger at an alarming rate, sucking in and absorbing everything. Without a creator to control their creation, it will go out of control, much like the guyver and it's meaning. And out of control it went, absorbing planets, matter and stars. Then, it started to consume Galaxies. And with them, the entire universe was absorbed, leaving nothing but a blank canvas. All that matter that the wormhole absorbed turned into energy that needed somewhere to go. And the only thing in sight was Sho's guyver unit, so that's where it went. The amount of energy being put into it was so vast that it needed to evolve to be able to hold it all. The unit, now more stronger than ever before, becoming slightly bigger. As it goes through the wormhole, Unit began to see a different world that looked similar to their old one. Unit sees that, unlike the old one, this world doesn't have zoanoids, or zoalords. It didn't have any advents to mess life, everything was natural evolution, billions of years of it, so humans didn't have monster forms. Instead, this other world has demons, more weaker, but more versatile zoanoidlike creatures with a weakness to the sun.
It also saw that humans, calling themselves demon slayers, fighting against them with what they call breathing techniques. Unit was intrigued by the way some danced around their opponents, before beheading the demons they were fighting. It was beautiful, so much so that Unit decided to download every and all breath types, only possible after it's evolution. However, because it was so much information to go through, over 400 years of it, Unit shut itself off to process it all.
While it as doing that, the wormhole came to an end, before spiting Unit out into the middle of a forest, where it hits a young boy in the back of his head, making the boy fall to the floor. The boy, who looked to be about 10 years old, had fair skin and blue eyes. He had black hair going past his shoulder blades tied up in ponytail. He also had on a blue haori, and slightly baggy pants.

The boy got up from the floor, groaning a bit at the pain the back of his head was in.
The boy: Ow, what the hell just hit me. What is that?
The boy looked at the circular object that had hit him in the head, it had a strange orb in the center of it, with what looked to be wires wrapped around it with bluish metal plates covering them.

The orb glowed faintly, pulsing every two seconds as if calling out to the boy, who, with his ever growing curiosity decided to pick it up and examine it, bringing it up closer to his face.
The boy: Wow, it's so light. I wonder what it is?
The boy wondered how something so light could have hit him so hard, he felt he had a slight bump on his head. As he was examining it, he accidentally brushed his fingers across the orb, which glowed brighter. The wires had begun to shift and move.
The boy: What is happe-...
The boy didn't get to finish what he was saying, before the wires burst out of its metal shell and began to wrap around the boy, covering his whole body, and wrapping around tighter by the second, causing him immense pain, so much pain that he couldn't even scream.
The boy thought's: What's happening to me. I can feel it going under my skin and into my flesh, it hurts so much, I don't think I'm gonna make it. I'm sorry nee-san, please live a happy life.
That was the end of his thoughts, as he passed out. A few minutes later, in the boy's place stood a new figure. He was slightly taller than the boy. He was covered in a bluish gray armour, with blades on his elbows, with a fin atop his head.

The eyes flashed red and the orb glowed briefly before stoping. Suddenly, the boy's voice distorted by the helmet on his head asked,
The boy: Wha- what!?
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Author's note: This is my second story, so I hope that you'll enjoy it. Good bye for now.