Labyrinth "Kaishin Oubo".
　It is one of the labyrinths created during the Third War of Heroes and Demons. During the war, the soldiers of the Kingdom of Terraria conquered the labyrinth at a relatively early stage, but due to the abundance of resources that can be obtained inside the labyrinth, they dared to allow it to continue to exist.

　The entrance to the labyrinth was about two hours away by carriage from the south gate of the royal capital.

This is the entrance, isn't it?

　Mize said in a slightly tense voice.
　At her feet was a large staircase leading to the basement.

　This time, we were asked to investigate the topography of the fifth level of the Kaishin-oubo tomb. It seems that an earthquake had occurred here last month, and this survey was to confirm the effects of the earthquake. It is not that the whole of the five layers collapsed, but that the floor and ceiling, which were originally on the verge of collapse, are being investigated. The guild's receptionist marked our destination on the map we bought at the store, so we probably won't get lost.

　Before starting the search, I called out to the four of them.

"Have any of you ever been to the Tomb of the Deep Sea before?

　Oz and Gran raised their hands in response to this question.
　Oz raises his hand here, as he had done in advance. It's better to reveal what you know about the structure of this labyrinth now, so that you can be more convincing in guiding the way and evacuating in case of emergency.

I had a chance to go inside for a little while during the war. What about ...... Oz?

"Boku?　Hmmm ...... killing time!

　Oz replied to Gran's question with a carefree smile.
　You can't say that the agency's mission was to explore, but unfortunately, this answer of hobby is also correct. I'm pretty sure that during the war, Oz dove into reasonable labyrinths in between missions, because he didn't want to dull his skills.

I'm not sure if it's the same thing, but I think it is. I'm sure you're not surprised, Oz.

　Mize says with a wry smile.

I bought a map, but if you have someone with experience, should I trust you to show me the way?

　I bought a map, but if you have someone with experience, should we let them guide us?

I'm sorry. I don't remember any directions.

Neither do I.

　After hearing both of their replies, it was decided that Elysia would carry the map as planned.
　Gran and I led the way, with the women following close behind.
　As we descended the stairs, the light outside gradually faded away.

"Mise, the torch.

"Yes, yes!

　I signaled Mize to light the area with the torch.
　We reached the first level of the labyrinth, the Kaishin-Ohbo, and checked our surroundings on the spot.

　It was dark until we went down the stairs, but when we reached the inside of the labyrinth, there were lights everywhere. Candlesticks attached to the walls were lit.

This is the labyrinth ......, it's much brighter than I expected.

"Well, this place has been explored by many adventurers because of its proximity to King's Landing. The torch I brought with me is like an insurance policy.

　Gran explained to Mize's murmur.
　The adventurers are also trying to keep the labyrinth well-lit for their successors. It was no exaggeration to say that the brightness of the labyrinth was the goodwill of the adventurers themselves, as the demons rarely turned on the lights without permission.

Is Oz familiar with the labyrinth?

"Hmm, I don't know. I don't know. It's been a while since I've explored a labyrinth the right way.

"The right way?

　Elysia tilted her head.

The labyrinth is a very flexible terrain. For example, if you feel like fighting a demon is too much trouble, you can use the poison gas you prepared beforehand.

"Oz.

　I was about to say something unnecessary, so I stopped him.
　Oz immediately understood my intentions and apologized, sticking out his tongue.

"Oh, this... Is it a ...... herb?

　Suddenly, Mize bends down, stares at the grass growing on the ground by the wall and says.
　The grass she was staring at was familiar.

The grass she was looking at looked familiar. "...... That's the herb we used in Potions class. I didn't know they grew in places like this.

I've heard that the labyrinth contains all kinds of resources. So it's true.

　Mize said happily.
　As they resumed moving, Mize kept his eyes on various things that came into view. She didn't go over and pick it up, probably because she felt bad about stopping everyone each time, but she was still scurrying around, so it was obvious what she was thinking.

"Mise. Do you know why there are resources in the labyrinth that are useful for human life?

　Inspired by her amusement, I posed a question about labyrinths.

I'm pretty sure it's ...... to invite people in, right?

Correct. A labyrinth is a nest of demons. And most of the existing demons feed on humans. That's why labyrinths are designed to invite in humans, who are food for demons.

　You do know this much, don't you?
　It seems he was not just aiming to be an adventurer. He seems to have a minimum of knowledge.

I'm sorry to interrupt your little discussion, but I'm here.

　At Gran's words, Mize and I stopped talking.
　The shadow of a demon was approaching.