Isekaid 40ish Man Returns, Regressed as a Peerless 17-Year-Old

The place I chose to train with Yui was at the dark side of the moon.

In the end, I decided that this was the safest place.

I’m the one who decided it but….carrying someone else outside the atmosphere consumes more magic power than expected.

This will be hard to do every day.

I’d like to say it out loud, but Yui will probably ask, “Are you saying I’m heavy?” so I just kept my mouth shut.

My body wouldn’t be in a bad situation but if a powerful variant appears, there’s a chance that I wouldn’t be able to protect Yui due to being too exhausted.

「Amazing….it’s the universe….it’s the universe, Kazu!」

Yui held my hand using her two hands while jumping. That should have been okay if only her miniskirt is not gently flipping in space.

Even so, I love seeing her smile like this.

I have to use a lot of magic power in today’s training so we can’t do it on earth since variants will surely feel it.

「What are we going to do for today’s special training?」

Instead of answering Yui’s question, I spread my hands out and made a circle with my arms.

「I’m going to optimize Yui’s internal magic circuits to the limit.」

「Eehto…you mean?」

「Like the grand elder of the Planet Namek.」

「I have potential too!?」

「It’s not that occult and there’s a theory behind it. However, in a similar sense, your power will rapidly increase but only once.」

We’re doing it with magic so it’s not really supernatural.

Yui has the talent to control magic power. That’s the reason why she can use a divine object.

However, her body is being forcibly used by the divine object.

If you compare magic circuit to blood vessel, you can say that using a divine object is similar to a person that is suffering from high blood pressure.

Though if I use this analogy to her, she might get angry….

I can explain it to her as a defragmentation of a PC but I don’t think that would go well.

By the way, manual defragmentation will be gone in no time. It’s amazing how far technology has evolved.

-0-

In any case, it makes the flow of magic power more efficient while also allowing the body to withstand high output.

You should optimize it frequently depending on your own ability, but the first time is the most effective.

I have done it lightly on her before but now, I’ll do it in earnest.

At the same time, I will also optimize the divine object to make it more suitable for Yui.

「I’m going to circulate an enormous amount of magic power between you and me. It’s quite stimulating so be prepared.」

「O-okay…」

Yui swallowed hard.

-0-

Enormous magic powers gradually circulate between me and Yui, who are in outer space.

From my right hand to Yui’s left hand.

From Yui’s right hand, to my left hand.

「Ahhhhh……it feels greatttt….t….ahhhhhhh!?」

Yui’s body was in a state of intense pleasure.

Pain comes when the magic circuit is forcefully expanded while pleasure comes once it is improved.

「Kazu….how long will this last….?」

「About three hours.」

「I……will probably go crazy first….」

「………」

「Say something—-ahhhhh….kufunnn….」

I’m doing what I can to maintain composure in front of Yui, who is writhing around sexily and convulsing, which also made her big boobies shake.

It’s already at a level where I can’t help but feel sexual desire.

-0-

3 hours later.

「Alright, it’s done.」

「Fuehhh….haaa haaa….over….really….?」

Yui, who’s out of breath and drenched in sweat, leaned over to me.

Something soft is pressed against my chest.

Gently supporting Yui’s body, which twitches occasionally, I desperately deviate my consciousness from the softness I feel.

「Haa haaa….no more…..I’m soaked all over…I want to take a bath….」

I guess I’ll have to check the effect later.