The One Beneath None!

The demon lord was still unconvinced so he threw a weak attack of his own.

A small pitch black orb hit the barrier...and like the attacks before, it too seemed irrelevant.

Again before anyone could react a bolt flew out... anyone other than the demon lord that is.

"Naive, you think such a small trick can work one". With that the demon lord evaded the bolt.

Just when he was about to gloat, the bolt turned around, he sensed it a blocked with his left hand.

boom!

A small explosion went off on the palm of the demon lord.

The rest of the demons were elated noticing that the demon lord seemed to be find even after such a direct hit.

"Men, let's regroup for now, we need to study this barrier more before we can make our move and it's not like we had to wipe out the humans anyway". The demon said to his soldiers before flying off in the direction of the demon capital...

When he was a distance away from the soldiers and dukes, the demon lord unfolded the fist he'd made with his left arm.

On it an inch deep wound could be seen, he had been using his mana to hold back the bleeding.

"Damn!, to think that even a rebound from less than a percent of my power cab actually hurt me. Then again lightning just happens to be one of the two elements we demons are weak to after all. But still, doesn't this mean if I had gone all out but failed to destroy the barrier, I would have been erased like the rest instead?! That was too close, way too close for my liking....I wonder if it's the same monster behind the sages who did it, I'm not sure if I want to meet them anymore, might be on the level of that thing...."

And with that monologue the demon lord spend into the distance before vanishing.

...

Inside the barrier....

The humans had been keeping watch close to the barrier to see if it was really effective. This was because they had done they're own experiments throughout the week. They had realised that touching the barrier didn't do anything to them. So they were worried if it was the same for the demons.

After witnessing the whole episode with the demons the humans felt like they had won the lottery. To make sure they captured the runaway slave and interrogated him. His testimony backed up what they had already observed which made them even more happy.

Nobody knows where or when the rumor began but soon repelling the demons, they started calling it "The Heavenly Barrier"

...

The day the barrier was erected, soon after the two year declaration, back at the cabin...

"That should be enough for you girls right?". The young man said looking a bit tired since he'd just used quite a large amount of mana too quickly.

"...."

"...."

"...."

"...."

"Well... saying it's enough is an understatement, I don't even know what else to say, you're a monster, no you're beyond that". The redhead said after collecting her chin of the floor while the other girls just nodded in agreement still in shock.

"So I did what you wanted and now you're dissing me by calling me a monster?!"

"S..sorry, we don't mean it in a bad way and thank you for what you have done for us it means a lot". The redhead said with an apologetic expression on her face.

"It's fine, even I know what I've done is absurd...but hey, at least it means my dream is getting closer and closer to reality right"

"You're still going on with that?"

"Of course I am, I won't ever give up until it becomes reality!!"

"You're crazy...but then again you might just be crazy enough to do it..."

Like that, the banter in the lonely cabin continued....