Tensura x Kumo desu ga, nani ka. Crossover.{COMPLETED}

Side Story 1 : Rimuru visits Tbate (9)

Rimuru pov:

After returning from the relictombs, I just layed down in bed and started to assimilate the next layer of my aether core. The aether core which is assimilated with my mana core is now causing my mana core to breakthrough into the next stage and considering I was at white that is a major achievement.
After I got out of my stupor, I continued refining my aether layer which automatically refined my mana core.
Throughout the night my mana core started forming cracks and when I was about to breakthrough into the next stage I walked to the forest besides the mansion. In the middle of the forest was a clearing in which i sat down and continued refining my core.
After three hours the cracks reached the center of my core and my body started changing, my core dissipated and the mana coming from the now dissipated core, merged with my body and made it change, the fact that this is a puppet body is the reason this works at all.
My true body wouldn't accept a core even if she wanted to have one.
The dissipated core was merging with my very being and changing it into an actual body.
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After another hour of this merging, my body had assimilated with the core which was now my body, when I searched for my aether core, I found it in my sternum in the place of my mana core. The aether core started to assimilate with my new body and assimilated with my system.
When I tried absorbing ambient mana and refining my mana core(now mana body), the only thing that got stronger was my physical state, the once high-universal strength is now low-multiversal.
Apparently my mana core was on the same level as my body, so even at the black core was my core stronger than other by a large margin.
When I finished getting used to this new body, I walked to the dining room, the sun was already up and at the point where it's time for breakfast, as I sat down, I felt a few stares on me.
"What were you doing yesterday, I didn't find you in your room, but I did find a portal, I didn't enter it, but I was pretty worried you know." Virion had said. "I was in a place called the relictombs and I was there to help the little ones grow stronger."

"How would you do that?" Asked Merial with a concerned gaze.
I pondered what to say, but I eventually went with the truth.
"I'm gonna help Tessia awaken and help Arthur form something called an Aether core, I will also be making that for Tessia, but she has to grow a little otherwise her body would be incapable of handling the power."
They looked at me in surprise, but since the kids weren't here we couldn't make the decision for them except for Arthur, I'm his guardian after all.
"Very well, but could you please wait with that, I'm very close to helping Arthur awaken his beast will."
His words surprised me a little, but I didn't show and continued "I wasn't planning to do it yet either, I don't have enough resources yet to help Arthur with his aether core."
"Thank you, but you do realize I'm gonna torture him in his training right?"
"Yes Virion, as long as he's still alive I'll heal him from any and all wounds."

"To my next topic, I will be asking you if I'm allowed to make Tessia a hybrid?"
They looked at me in surprise and suspicion, but I just waved my hand and answered "What I mean to do is make a hybrid in order for her to grow stronger a lot faster, because otherwise she'll grow at the max speed an elf can progress and I apologize for my rudeness but it's too slow.
In order for her to grow faster in power, she also needs to grow in body. And that's the reason for the hybrid body, you will still be her biological parents as I will only change race of DNA and not all DNA."

They stared at me and said "If Tessia truly wants it then I have no problem with it." Alduin said.
"I also have no problems with it." Said Virion.
"Are you two serious, we're talking about our child, what if it fails or something bad happens?" Merial answered.
"Don't worry Merial, nothings gonna happen to her, only her body would grow faster in order to keep up with her power, so it could be possible she goes through 8 years of puberty within one year."
I assured her.

"But what about her public image, she's just 4 about to become 5. What if she is fully grown when she still 7 or 8?"
Merial continued.
"Don't worry, the earliest she would be fully grown is when she's 11 and I can place a seal on them after training their power, this would allow them to switch between child and adult form for the public and yours convience." I said, she seemed to calm down and stared back at me and nodded.
__
As I was walking towards Arthur's room, I noticed the door was open, not fully, but just a little, when I peeked inside I saw Tessia and Arthur sleeping in the same bed Arthur was spooning little Tessia unconsciously coating the both of them in mana.
I was impressed by his automatic defense, but it was to weak, Soni just flicked his head with my finger and Arthur woke up screaming in pain and holding his head, while Tessia was stirring and let out a yawn.
"Wash up, your training is about to begin. Visit the dining hall first though, you'll need to eat to keep your energy during the training."
Tessia walked towards the bathroom while Arthur followed, I picked him up by the scruff of his neck and asked "What are you doing?"
"Following Tessia, we need to wash up don't we?" He asked with an innocent tone, which I could sense was the truth.
I smiled at him and let him enter.
"He's getting very close to being Arthur and abandoning Grey."
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The end.
Hope you enjoyed the side story.
And for information all my chapters are around 1000 words big.