The Wandering of an Unstuck Stepbro: Multiverse Travel

(Ryoto's pov)

We knocked on the door to the mansion and waited for someone to open it. As we waited, Rin decided to start a short conversation.

"So, what do you think Mikado-sensei will test?"

"Well, I hoped to test most things. Mikado-sensei is one of the best doctors in the whole galaxy, and I trust her expertise. As you've seen, she managed to create gigai by herself without any help as far as I know. Maybe there are some alien spirit species in need of bodies like that, but I'm not sure. The point is that she is good, and she can help us figure out our limits in a safe environment, and she'll even give us some kind of explanation. She even worked on my eyes and blood before."

"And you trust her that much to tell her our secrets?" She inquired, and I nodded.

"There's a reason everyone knows of her. She heals you, doesn't ask many questions, and doesn't sell your information. She would be a good black market doctor with these ethics. Maybe she is, but I don't care that much." I shrugged my shoulders as I said the last bit and petted Yoruichi (cat), who was still sitting on top of my head.

What is with black cats and my head? Is it really that comfortable?

Then, the double door opened suddenly with great force, and Ryouko, with a disheveled appearance and an excited/crazy expression, appeared at the entrance. The kind that wouldn't look strange on Mayuri. Once again, I suddenly doubted my trust in this doctor.

"I was waiting." She said, still stuck in the position when she opened the doors.

I looked at her for a moment.

"I didn't notice." I said sarcastically.

Noticing what I meant, she quickly and hastily tried to fix her appearance with some degree of success. She then welcomed us inside, and only then did she notice a cat on my head.

"Her name is Yoruichi, and I picked her up today on the way here. She likes my head."

Mikado decided not to prey more into it and just accepted it as it was, but she changed into the main topic.

"I spent the whole day thinking about today's examination. You didn't give me many details, but knowing you, it could be anything. That's why I prepared everything I could think of in addition to what I already knew."

"You seem excited." Rin commented, and Mikado was happy to explain why.

"How could I not!?" She turned her head at impressive speed towards Rin. "Ryoto's eyes and blood alone are something of a dream for any researcher and scientist. And you two came in here with more hopefully unknown abilities. Also, did your eyes change?"

The last comment was about Rin's eyes. I noticed that she was using a Kido that she had developed herself. It wasn't anything special, and it was reasonably simple, making everyone see your eyes in any color you wish for. It was also user-friendly as it didn't use up a lot of energy to keep it up. I was never working on creating new Kido, but I was never that good with them. My Hollow Reiatsu was too wild for such delicate work, but I still learned somewhat complicated Kidos whenever I could.

Rin then stopped the Kido, and with the blink of her eyes, one of them changed colors into blue.

"Fascinating. "Mikado observed Rin with interest on the border of obsession. "Do you have the ability to control the color of your eyes, or is it an illusionary ability? I once met a species of aliens that were able to create gas in their bodies that would make others hallucinate. There's also Balkean's mimicry ability. Ahh~ So many possibilities~."

Ryouko isn't right in the head today. I think I may have broken her, and I didn't even reveal anything yet.

"So, where's Oshizu? I can't seem to find her in the whole mansion." I asked, not only to change topics for a moment but also out of genuine curiosity, as I couldn't pinpoint her location in the whole mansion.

"Shizu? I gave her a free day. Seeing her reaction yesterday to both of you, I was expecting her to disturb today's research, whether she wanted to or not. When she gets used to you, we can test even more things. Speaking of which, can you explain the cause of it? I think she called you Shinigami."

Rin and I exchanged looks, and after turning back to Mikado, I spoke.

"What do you know about multiverse theory?"

And so I explained Rin's and mine's small adventure while avoiding some details. The short version was our souls were sent to another world/universe, what can we do, and what we were planning on testing. I also requested an ordinary examination of our bodies. I was curious how they changed because the body reflects the soul, and the soul reflects the body. If one changes, so does the other, so it's strange for me when my and Rin's bodies stay in their teenage state while our spirit looks like they are in their mid-20s.

Throughout the whole story, Ryouko took notes. Any information that was new, interesting, or useful was written down.

"Fascinating... truly fascinating. Do you realize what you just shared with me can change everything. Other worlds are full of different technology, different rules, new resources, and possibly everything else that you can imagine and more. Knowledge about this in the wrong hands could not only be dangerous but also catastrophic. Many organizations, nations, and whole planets would try to cross dimensions if they had proof that it was possible. It would create a whole new arms race. That's why it should be kept a secret."

"Then we are on the same page. It's not like I'm planning on announcing what I went through." She nodded at my agreement.

"If we agree on this, then we can begin the examination." The excitement in her eyes returned. You said that you wanted to do a check-up on your bodies. I was expecting something like that, so I prepared a machine just for that. If you remember, it was the same machine I used on you when we checked your blood. I upgraded it since then."

She led us to the machine and told us to strip down to our underwear. I was never one to shy away from showing my skin, so with a flex of my muscles, I lost both my pants and shirt. Speaking of which, it felt strange wearing modern clothes. I was more used to traditional Japanese clothing, so being out of them felt better.

Rin rolled her eyes at my display, but she was already used to it, so she didn't even attempt to make a comment. Ryouko checked my body, but not in a sexual way. She inspected my wounds, but only that. She didn't try to get closer to me and touch them or anything however, her expression softened a bit.

I told her that I was in a lot of fights, war even though it was short. I even said to her that I got some scars that I kept here, but I bet she didn't expect something like that. Most of my torso was scarred, and a little bit on my arms and thighs. It was the body of someone who had seen battle and danced with death too often.

I put Yoruichi down and walked inside the machine. From what I understood, it would scan my whole body to give Mikado more information about everything. The machine was working quietly, and as I waited inside, Mikado was working on the computer, analyzing the data she had gathered. Shortly after, the door opened so I could exit the machine.

Next, it was Rin's turn to strip, and she didn't shy away either from being seen in her underwear. After all, Mikado and I were the only people here. She repeated what I'd done moments later, and soon she joined me by my side as Ryouko went over the detailed results of the test.

"Hmm... It's strange. As far as this shows, in terms of her anatomy and biology, Rin is an ordinary teenage girl. There are a few inconsistencies here and there, of course. Your body also shows traces of pregnancy, but it's in a way that looks like it happened a long time ago."

Mikado started a bit confused, but Rin was happy to clarify.

"No wonder. It was about 150 years ago since I got pregnant." Rin said calmly, but Mikado was stunned by the revelation. Did we forget to mention this little detail?

"...I see, but it still doesn't explain why the rest of your body has the making of a teenage girl. Why do you have very old traces of pregnancy while everything else stays the same." She then turned to me. "The same could be said about you, Ryoto, but to a smaller degree. Some of your scars are much older than others, but your body still seems like a teenage boy's. However, I can't call it ordinary, no matter what. Your muscles are denser, your blood is poisonous, your eyes are extraordinary that I can't even begin to describe it, and there are a few strange things here and there. It's amazing."

She spoke so much and so fast that she forgot to breathe. I think I also saw a bit of drool at the corner of her mouth.

After this, we went over some ordinary tests, such as strength tests, speed tests, and so on.

Apparently, I got stronger and faster than I had been before. My instincts also got better. Despite my body staying mostly the same, it also somehow changed. What surprised Mikado was that Rin also was supernaturally strong. Impossibly so. Her body shouldn't have been able to support this much weight, but she did it anyway. I theorized that the strength of the body was proportional to the strength of the soul. Oshizu could still use her ghostly powers while in her fake body, so it's not strange that something similar is happening to us.

Mikado also wanted to have more of my blood for more research. It was time when I mentioned that I could finally control the intensity of my blood. That revelation made Ryouko want to have as many samples of my blood as possible with different strengths and intensities. It was then that I learned that I can even make my blood stronger than it was originally. It was so strong that the most potent poison Mikado had on hand didn't even have time to start circulating in my system, as the moment it entered my blood circulation, it was gone. It was destroyed instantly, and the poison wasn't weak, far from it. The strength of my blood shocked even me.

I should set my blood to be harmless enough that it wouldn't start dissolving anything in contact with it but still deadly enough that it would be able to slow down any possible poison, just in case. The speed at which it can become deadly was instant as well, and with my reaction speed, I shouldn't be killed by anything. Better to be safe than sorry.

Then we tested some Kido. Not every single one we know, of course, because it would take too long, but the most basic ones would give us an idea about their power and versatility in a body made of bones and flesh. There wasn't much difference overall, but using the energy was more delicate, as we already noticed when we used Kido the first time here.

Then we tested our eyes. Rin's eyes were obviously weaker than mine, but she had most of my abilities, although watered down. She didn't even need to close her 'normal' eye to use it fully as both of them held power, and the color change was mostly symbolic if nothing else.

Rin didn't have much more to test after this, but I had a few new toys to play with, and I couldn't wait to try them out.

First, Vector Manipulation.

"So Mikado-sensei, ready to have your mind blown?"

I asked with a cheeky smile because what I was about to show her was arguably the most insane of my abilities. If used correctly, it has the potential to control some of the laws of physics.

"If you have anything crazier than what you have already shown me, then I don't know how I'll react. It's not like you have the ability to control... I don't know... let's say vectors. It would be absolutely absurd."

Seeing my expression, she realized that she hit the nail on the head, and her eyes went wide.

"Oh my God... You have the ability to control vectors..."

Without any warning, she threw a pen at me. It was incredibly slow, from my perspective, and I know why she did that. She wanted to see my ability in action, so I gave her exactly what she wished for.

It was the first time I tried using Vector Manipulation, but thankfully, I got the hang of it. Otherwise, it would be embarrassing if the pen hit me in the face.

Before the projectile reached me, it flew in a completely different direction at a much higher speed and accidentally went through the wall.

Too much power... I thought my calculations were correct, but they were a bit off. It seems I didn't account for everything, Not to the point that I would get smacked by something, but I will need to train with it later on.

"Incredible! It wasn't telekinesis, control of air currents, or anything like that. You changed the Vector of the pen to change its trajectory and speed. The data I got from this small test says it all!"

The reason I wanted to test Vector Manipulation and, for example, not my elemental bending is because I can train bending by myself without any worries about the destruction of my surroundings. Just training my forms is enough, but even using both fire and water, I can do it relatively safely. This ability, however, depends solely on my capability of calculation, and if I'm off, the results could be catastrophic. That's why I wanted to see how it would work in a safe environment, and I was right, as I made a small mistake just now.

Seeing my new ability, both Rin and Yoruichi raised their eyebrows. I wasn't surprised at Rin's reaction, but my new cat seemed to have eerily human expressions. Seeing that I was looking at her, she meowed cutely.

Am I overthinking? Did Aizen really mess me up so much that I doubt an ordinary black cat because she looks like Yoruichi?

"Ryoto!" Mikado called me. "If you have anything more than that, I'm not sure my heart can take it."

"Then it's a bad time to say that I wanted you to take a look at one more thing. I don't need you to examine everything about what I'm about to do. I just wanted to test out this ability at least once to know how it feels. It's transformation ability, by the way."

Ryouko looked like she didn't have any more energy to get excited, so she gestured for me to start what I wanted to do. Her eyes were still sharp, meaning that she was still analyzing everything I was doing.

I closed my eyes, took a deep breath, and released the air from my lungs. I repeated the process a few times until I felt ready.

Then I suddenly opened my eyes and gritted my teeth. My whole body started growing white fur with black stripes. Then my limbs started growing, all my muscles growing denser and even growing new muscles. My whole skeleton was changing, and I wasn't able to stand on two feet anymore and was forced on all fours. From the back, a tail appeared, and at the end of my now paws, large and certainly very sharp claws popped out. In my mouth, my teeth became sharper and longer, especially my fangs. Teeth that are perfect for an apex predator. On top of my head, a pair of cute feline ears appeared, and one of them flicked at the end. The transformation ended with me roaring for no particular reason, but it quickly turned into a yawn.

I looked around and saw shocks on everyone's faces. Yoruichi, on the other hand, was acting strange. She approached me and started rubbing herself on one of my legs. It looked comical with the size difference between us. She even started licking me and purred. Then she rolled on the floor and showed me her stomach as she blinked slowly at me. For some reason, I had an urge to lick her back as well, but I stopped myself. I took her, however, by her neck in my mouth, which was challenging because of my new size, and gave Yoruichi to Rin, who wasn't scared at all despite my new size. I was larger than any living tiger, but I was still smaller than the Hollows we faced. The rough estimation I would give myself was that I was about 3-4 meters tall, but I looked much more prominent thanks to my longer body. Not to mention that she knew that it was me, and she didn't have any reason to be scared of me.

It was worth mentioning that my scars were still visible in this form.

Not waiting for anything, I started changing my form again. This time into my Hybrid form. Every Zoan Devil Fruit user has at least three forms to choose from. The Human form, the Beast form, and the Human-Beast form is the form I'm testing out right now.

In this form, I became bipedal, with most of my beast traits still present. I checked my body a bit until I was satisfied, signaled by a nod of my head, and returned to being human.

"... I think I'm going to sleep on all these new discoveries because I'm afraid I really am going to go crazy. I worked on some unimaginable stuff before, but you managed to beat all of it, Ryoto."

"I'm always happy to pleasantly surprise." I answered.

We didn't have anything more to do here, and Mikado-sensei will need time to review everything she learned today, but this examination was a success overall.

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END

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