It’s just about been two months and Dad has taught two-digit addition, and subtraction. And just as I had previously thought, they used a more traditional method unlike us on earth. Although it wasn’t bad, it would be extremely slow when you consider larger numbers. Not to mention, multiplication was so basic that it was painfully slow. Although dad was pretty quick in it, I’m assuming it’s due to the experience he has from doing it a lot.

And once dad’s class was done, I would teach Vira about vertical addition.

「Vira, so if the number exceeds 9, we put a zero here and carry over the one.」

「Uncle, is that why it’s called a ‘carry’?」

「Mm, yeah.」

He was slow, but once he had understood a concept he was able to replicate it. Although at points he did have trouble, he was overall a good listener and learner.

I also did all the problems and sums on the ground since I didn’t want to show any of this work for now.

He had enough practice and this was a good point to show dad what we’ve been working on. I don’t want to teach him multi-digit operations until Dad feels ready for it. I only want to teach side-by-side with dad, this’ll ensure that he learns in the proper order and he learns well with a good foundation.

「Vira, wanna show dad?」

「Yep!」

“Dad! I wanna show you something I was learning!”

“Mm, vira? Sure, go ahead.”

“Can I use the board?”

“Sure.”

“Dad, can you give me two numbers?”

“Hm, 20 and 35, let’s say.”

“Okay then.”

Vira then wrote it on the board but vertically. I never told Vira how to explain, so I’m looking forward to how he’s gonna explain.

“Okay dad, since there’s a zero at the top, and only the five is here, we’ll put the five below the one’s place. Then we have 2 and 3 in the tenth’s place, so that’s 5, which we’ll put in the tenth’s place. Which means the resulting number is 55.”

Dad opened his mouth in shock, it wasn’t because the addition itself was impressive, it was the fact that we had done it so quickly, of course compared to dad’s speed we were still slow. But to Vira’s previous speed, this was phenomenal.

“Vira.. Who taught you this..?” Shi-

「UNCLE!! WHAT DO I SAY?! WE DIDN’T DECIDE THIS BEFORE!」

「UH, I DON’T KNOW, WHAT DO WE SAY?!」

“You know what. It doesn’t matter Vira. All that matters is that you did well here, what’s this method called?”

“Vertical Addition.”

“Hmm, I see. Okay. Can you explain to me how it works?”

“Mm, sure dad.”

「Uncle, can you explain please~?」

「Fine, I’ll do it.」

I soon explained to dad about how it’d work with an example, “If we were to say add 99 and 99, we’d have 18 on the one’s place, and so we’d put the 8 down here and carry the one over to the tenth’s place on the top. Which means when we add the tenth’s place, it’d be, 9 + 9 + 1, which is 19, and since we have a hundredth’s place as well, we can just put the 9 in the tenth’s place and put the 1 in the hundredth’s place.”

“I see, so the leftmost digit is called the one’s place, whereas the second leftmost is the tenth’s place, and then the hundredth’s place, then the thousandth’s place and so on.”

“Mm, yes.”

“I’m assuming subtraction can also be done this way?”

Hm, I can’t explain this to him since I haven’t taught Vira about this, not to mention I’d have to tell him about borrowing, so I’m gonna say I haven’t thought about it yet.

“I haven’t thought about it yet. Sorry dad...”

“It’s alright. You did well.”

He thought about something for a bit and then said, “Vira, can you teach Stella this method too?”

“Sure dad!”

I then studied a bit more magic books for the day and went to sleep. But today was a good day, Stella is also steadily learning the vertical-addition method.

“Hak, you saw that too, right?”

“Yes, master.”

“It was like he changed into another person... First the language, second magic, and now this, nothing makes sense.”

“Master, are you suggesting that there may be another person within the young master’s body?”

“Well... yes, it’s not like there aren’t records of this happening, albeit old.”

“What should I do, Master?”

“Nothing. Because I’ve tested something and Vira seems to remember everything even while this other person is in control. Not to mention, this person calls me dad. This may just be my love as a father bleeding into the matter, but regardless I don’t think this person has malicious intent.”

“I see... Master. Then, should I treat them the same?”

“Yes. At all costs, do not let anyone know about this, not even Vira. I’ll talk with her today.”

“The lady?”

“Yeah.”

Soon he had reached home and talked with his wife. Yet she replied, “I knew already.”

“How..?”

“Honestly, did you think I wouldn’t know as his mother?”

“N-no, it’s just...”

“I know that you’re afraid dear, but you shouldn’t be. Every year that I’ve raised my boy, I know he means nothing but love towards us. He’s the same sweet boy you always knew. He’s talented, kind, compassionate, not to mention, so adorable~”

“Should we ask him about it..?”

“We’ll listen to him whenever he’s ready to tell us about it,” she stopped and then continued, “Because he’s our son.”