StoneBound (Previously Goblin Fairy)

Note: This used to be Goblin Fairy, I changed it. A Dungeon Core story, following a young man, who dies is reincarnated as a dungeon core, in another world. He quickly goes a little power insane, and starts killing things. One day he finds a goblin, tries to kill it, and the Goblin begs for his life before eventually informing the Mitchel, our dungeon core, that if a dungeon core doesn't receive a companion, usually a fairy, or spirit they will go insane. But nobody wants to companion with a murderous psycho so, instead the goblin will be his companion. Shortly after this our dungeon, become obsessed with other humanoids, and begins advancing on this. All the while above the ground, a young man Milo, buys up the mountain where The Dungeon is located, and in no time at all a city starts to form. Watch Milo fight off monsters, foreign invasions, bankruptcy, and all the people flooding through the portal from Earth. Oh, and there's a portal to earth there as well.