The Klein bottle. It allowed you to summon monsters and Heroes.
I had used it many times before, but it really was a mysterious artifact when you thought about it.
It came up to my waist in terms of size.
And yet, not only humans, but even much larger cyclopes had come out of it.
Well, it was the kind of mysterious artifact you’d find in the castle of a Demon King, so there was not much point questioning it.
As I stared at it with these thoughts, Eve explained it to me.
“There’s always a Klein bottle like this in every Demon King castle. Just like there is a core in every castle.”
“Are they all the same then?”
“Cores tend to differ in shape, but Klein bottles are the same. They all look like this one and are of the same size.”
“I see. So they all look like innards, like this one.”
“Yes. And they cannot be destroyed.”
“Really. Not even the most powerful magic spell will put a crack in them.”
“So it will be no use invading their castle and trying to destroy them.”
“That is the case.”
“Well, it would make more sense to go after the core, anyway.”
Eve agreed with a smile, but she also added,
“However, as you know from Demon King Eligos’s castle, the Demon Kings often hide and disguise or build iron walls around their cores. It will not be easy to destroy them.”
“Indeed. Well, it would be very odd if any of them didn’t do anything about their weaknesses.”
“Yes. Master, I think it is time that you think about some serious changes to your defense.”
Eve said with a worried voice. But I told her it was unnecessary.
“Why is that?”
She was anxious about my safety.
I would have to set the matter straight.
And so I borrowed the words of Takeda Shingen, a military commander from the country known as Japan.
“There was once a great general in the province of Kai. Though he was surrounded by enemies, he did not focus on the defense of his castle.”
“And why is that?”
“It doesn’t matter how strong the castle is if there is no one to protect it.”
“That may be true, but…”
“There is something that he once said.”
The people are the castles, stone barriers, and moats. Show compassion to your allies and vengeance to your enemies.
“What does that mean?”
“It’s what it sounds like. There is no point in having a castle without people you trust. On the other hand, if you have trustworthy subjects, you don’t need a castle. People are the castle. So be compassionate to them and don’t hate them.”
“So you are saying that instead of focusing on reinforcing the castle, we should surround ourselves in loyal subjects. Raise soldiers who will protect the core with everything they have.”
“That is wonderful. There must have been many competent generals like you in that country.”
“Yes, I would say so.”
“And did that general succeed in conquering the country?”
“No, he was unable to. But he became a great lord.”
“I see. That is too bad.”
She seemed disappointed, so I didn’t tell her what happened after that.
He had been intelligent, but he made too many enemies later on as well.
He ambushed his relatives, expanded his lands and killed his own son. Then he betrayed allies and used all manner of trickery to climb to the top. But once his son took over, it all came apart in a single generation.
Some say that it was the recklessness of the father that came back to haunt the son. Others say that the son tried to copy his father’s methods without actually having the skill for it.
In any case, the ‘castle of people’ that his father had built came crashing down.
Eve would just worry if I told her all of this.
She had enough work already, dealing with business and managing many other small things. And there was no reason to put a larger burden on her. And so I kept quiet and asked for some tea.
I began to think as I drank it.
A new part of this castle would be summoned through this Klein bottle now. But what kind of person would it be?
Would they be competent or incompetent?
Would they like tea or prefer sake?
There were questions to be answered, and it was best to get this summoning business over with as soon as possible.
I thought this as I drained the last of the tea down my throat. Then I tossed the ‘shuriken’ into the bottle.