Core No. 666 cut her communication from Kehma.

  They thought she’d continue toward the stairs as she’d been, but she didn’t.

  “Oh, it seems No. 666 started something.”


  “Oh, it’s true. I wonder what?”


  “It seems like she received an order from your younger sister’s Master…?”


  She began destroying the furniture in the nearby room with her sword—furniture like wooden shelves or the small closet within. Bang, bang, bang… everything was demolished and turned to firewood right before their eyes.

  “Really, what is she doing…?”


  “Is there a meaning to this?”


  Bringing the veritable mountain of wood chips to the wall next to the stairs, Core No. 666 thrust the doppelganger—the fire magic sword into it, causing flames to swell up.

  “… …”


  “… Wh-What is No. 666 doing?”


  Having began burning, the mountain of wood sent out plumes of billowing smoke. Some curtains she got from a nearby room was tossed onto the fire as well.

  Woosh! The fire became all the more fierce. It was too grand a fire to be lit within a residence.

  [Fufu, it’s burning well.]

  The fire scorched the wall and singed the ceiling. With this, Core No. 666’s—no, Kehma’s plan had become incredibly obvious.

  “S-Surely he’s not… surely he’s not intending to burn the mansion down!? Is he insane!?”


  “Ahahahaha! I’d expect nothing else of Kehma-kun! Who needs to think outside the box when you can just burn it down!”


  “… One normally wouldn’t think up such a method as this.”


  The Great Demon King was in shock, [Father] was in a laughing fit, and Haku was simply amazed.

  Still though, the fire was incredibly effective. The mansion was burning, after all.

  The larger one’s dungeon, the larger the effectiveness of the dungeon’s protection on the mansion would become. It could be repaired with DP, as well.

  It wasn’t to the point that it was impossible to destroy, though. Moreover, although it was hard to begin burning, it wasn’t as if it couldn’t burn. It would just look as though it was unscathed in the event its burned areas were repaired. Repairing through DP would create new construction materials, leaving the remains.

  Take the wooden pillars, flooring, ceiling, and stairs for example. If one were to destroy them just once, they would be reduced to ordinary wood. Therefore, it would lose the dungeon’s protection effect.

  In other words, it could burn. And boy would it burn.

  The destroyed walls were restored, as well as the pillars.

  However, they would once more be demolished and subsequently catch fire.

  Let’s assume she only broke the stairs that went up to the second floor to turn them into fuel. In the case that the Dungeon Core were on the top floor, the area below would become separated from the dungeon’s first floor. As such, it would immediately lose the dungeon’s protection effect and would quickly catch fire.

  And thus there was no choice but to repair them.

  But even then, Core No. 666 would simply continue to indifferently destroy them and feed the remains to the fire.

  The mansion absolutely could not be allowed to burn. Therefore, nothing could be done but to mend it.

  More destruction. More fire-feeding.

  Noticing that the repairs always started with the stairs, Core No. 666 focused on them as her priority.

  The stairs were repaired, destroyed, then fed to the fire. The stairs were repaired, destroyed, then fed to the fire. The stairs were repaired, destroyed, then fed to the fire.

  The process repeated several more times like a well-oiled machine, the fire growing larger each time.

  [Oh. This is nice. It’s actually fun. If only Rokuko had come along.]

  By the way, in the case where the core were actually in the basement, that would lead to the second floor and everything after being burned without the dungeon’s protection.

  As long as he intended to defend the mansion, he absolutely could not allow the stairs to burn.

  Would the fire cause Core No. 564 to abandon his mansion or cause his DP to run out first?

  Core No. 666, who was originally a fire magic sword, found fire to be a comforting existence. She didn’t mind any amount of fire dancing before her.

  The mansion-type dungeon, Core No. 666, and the burn-everything-down strategy. Everything formed a balance.

  “The more I think about it, the worse it gets…!”


  “Hey, is that Master a demon? He’s not really a human, right?”


  Although it was Core No. 564 that should have been the demon, from all appearances, Kehma’s methods were much more demonic.

  Core No. 564’s gargoyles came to put out the fire and ignored Core No. 666, but—


  [~?]

  She unceremoniously kicked them down. These gargoyles couldn’t even be considered proper opponents to her. Core No. 564 was likely starting to panic about now.

  “Alright, I talked with Kehma-kun a bit ago, so let’s try having an interview with No. 564 next! No. 6!”


  “If that is your wish, Father.”


  With that, he connected his monitor to Core No. 564.

  [Uoooh!? That blasted No. 666, stop it, stop! Gaaah! Don’t destroy those staaaaairs!!]

  Although they’d expected it, what they saw through the monitor was Core No. 564’s panic. From the other side of the monitor, [Father] laughed.

  “…. Cough.”


  [Ah! Great Demon King-sama! Th-This is… apologies for showing you such an unsightly manner!]

  “It’s fine. How are you progressing?”


  [S-Sir! Th-This is nothing! My Magnificent Self will show them true power!]

  Core No. 564 composed himself and said as such.

  “Hmm.”


  Core No. 6 nodded solemnly.

  [My Magnificent Self was intending to punish No. 666 for her impertinence, do you mind?]

  “Do as you wish.”


  [Thank you, Sir! In that case, things will be growing busy, so—gaaah, stop burning it!]

  With that, the communication was cut off.

  “Are you sure? Do as you wish?”


  “I’ve given up on him. I’d meant that there’s no longer any relation between us, Father.”


  “Oh hoh. You’re fine abandoning a 500 series? What a cold heart you have there, Demon Lord-sama.”


  “Drop it. I have no real reason to protect him, so I simply undid my protection over him… Well, me telling him that was simply to make him a better stepping stone for No. 666.”


  “Hmm?”


  Haku placed her hand on her cheek in thought.

  “To defeat a 500 series despite being a 600 series… is it that No. 564 is weak, or that No. 666 is strong? I wonder which.”


  “Both. No. 666 is a genius if I do say so myself. Moreover, she has rapidly grown since acquiring a Master.”


  Just then, there was movement in Core No. 629’s dungeon.

  It appeared that a succubus had somehow survived and was earnestly reciting [Summon Gargoyle] in attempts to put together some level of fighting potential. However—


  Naturally, it was shown by the map. Therefore, it was attacked by the gargoyles on Core No. 629’s side.

  The gargoyles and the succubus ran away even as they fought. Then, once they’d been driven into a corner—


  “Oh, the hero.”


  “And that’s check.”


  They were quickly annihilated. They’d likely not received any orders from No. 564. If not, they never would have lost their heading and ran into the hero.

  But still, there was no helping it. Core No. 564’s dungeon was currently being ravaged by a campfire of Core No. 666’s doing. Moreover, a total of two hundred additional [Enemies] had infiltrated his underground floors.

  “All he had to do was allocate work to his subordinates, too bad.”


  “Thinking about No. 66’s final days, even placing trust in one’s own monsters is a difficult thing.”


  “That’s… well, there’s no helping it, I suppose. I won’t butt into that matter.”


  With that, Core No. 564’s underground dungeon was being captured as well.

  The first floor had quickly been broken through.

  “But… are those squirrels?”


  “Yet another example of his brutishness… He’d flooded everything with water and fish before. I suppose this is less objectionable, but still.”


  Even with the DP-summoned gargoyles that were left to stay there, the swarms of squirrels quickly and freely dashed through the statues’ feet and ran their way through. Even if the gargoyles attempted to strike them down with magic, bullet-type magic like fireball and the like were simple enough to simply avoid.

  Clearly, the ones manipulating these were well accustomed to [Swarm] manipulation.

  “These subordinates of Kehma-kun’s are good.”


  “… What excellent subordinates. Enviable, even.”


  “Really. I think so too. I wonder if I could trade Misha… hmm. They’re better than before.”


  Although some were cornered against the walls, they were the vast minority. The rest scattered through the dungeon to advance their search. Soon after, they’d discovered the stairs leading to the following floor. They’d managed to explore an entire floor without so much as a single hour passing—a frightening speed.

  “His tactics are as great as ever. No. 6, how would you have gone about doing this?”


  “Hmm? Let’s see… a long-ranged offensive skill. It’s harder to deal with such a small size and number of enemies, but I would use a type of magic that would deal with the entire enemy within range completely. Poison would work nicely.”


  “So the Great Demon King of all people would resort to poison?”


  “Kukuku, I am the Great Demon King, am I not? What’s so wrong about that?”


  Like this, Kehma dominated together with Core No. 629 even upon heading into the mid-game.

  … Incidentally, Core No. 564 said something about punishing Core No. 666, but what was he planning? If he wanted to do something, he would be better off doing it sooner rather than later to put on a better show for his spectators.