Now I'm a Demon Lord! Happily Ever After with Monster Girls in My Dungeon

Yuki finds himself reincarnated as a demon lord in another world, and he’s been put in charge of a dungeon to boot! Once Yuki accepts that his fate hinges on the dungeon’s survival in a world where powerful monsters roam free and danger lurks at every corner, he begins gathering allies and bolstering his defenses. Within a few days, he takes on a legendary dragon, an adorable pet slime, and a vampire girl, but despite all his precautions, life as a demon lord in a dungeon constantly under threat...is surprisingly mellow? Of course, with such a colorful cast of characters (and possibly more on their way), Yuki’s bound to wind up in some trouble. Will he be able to pull off a reckless rescue mission? And how will he and his monster girls survive an invasion by a hostile human kingdom?! Join him as he juggles daily life, responsibilities as a freshly minted demon lord, and his growing family of monster girls and pets!

Yuki’s been reborn in another world as a demon lord—and his new life is going swimmingly! He continues strengthening his dungeon with his makeshift family of monster girls until, one day, a heroine arrives on their doorstep to take down the demon lord. Or, at least, that’s what she says before breaking into tears because the traps are too scary! Curious and unable to resist lending a helping hand, Yuki heads out to welcome the hapless heroine. The group then decides to take a trip to a human settlement with their new friend. They all have a blast as they go around shopping, eating, and sightseeing, but the fun comes to an abrupt halt when a ghost appears out of nowhere and starts attacking the townspeople one after another. Can the demon lord who just wants to live the good life pass judgment on this new enemy?!

Reborn as a demon lord in another world, Yuki’s story continues! He succeeds in entering the royal capital to hunt down the crown prince, who’s determined to threaten the sanctity of his peaceful dungeon life. What he finds there, however, is a darkly transformed city overrun with Undead. Deciding to go ahead of the hero Nell and company, he infiltrates the royal castle, where he stumbles into a misunderstanding with the castle’s maids while also somehow managing to rescue the captive king. Then, after finding his princely target, Yuki launches his attack! The prince’s behavior and the disturbing atmosphere blanketing the area strike him as odd, though. His suspicions aroused, he uses Analysis to figure out what’s going on, and a shocking truth comes to light!

Reborn as a demon lord in another world, Yuki’s living his best dungeon life! Things are more laid back than ever now that he’s returned from the royal capital. Or not—because the Dragon King, Gyuohga, shows up out of nowhere with his sights set on Lefi. “Become my mate!” he demands. This sends Yuki into a frenzy, challenging the Dragon King to a one-on-one fight! But Yuki’s got more than just that to contend with. A demon appears before him with a request: “I’d like you to meet the king of the demon world.” Intrigued by the idea of being a tourist in the demon world, Yuki accepts the invitation and heads off. What awaits him there, however, is a man with a pretty face and an incredibly shady smile...

Friend or foe, it doesn’t matter! Demon Lord Yuki’s letting loose in the tournament! Yuki’s second life as a demon lord in another world continues! He’s been entered into a tournament by the Demon King, and he breezes through the preliminaries. Just when he thinks he’s got the finals in the bag, though, he learns that there’s a human contender! Against this older gentleman who has a refined ability with his holy sword, Yuki finds himself overpowered. But he won’t be defeated so easily. If his admittedly lacking swordsmanship won’t get the job done, he’ll just have to bulldoze his opponent through stats alone! Meanwhile, Nell has been working diligently to secure alliances in the demon world. Out of nowhere, she’s attacked by a mysterious group of people clad in black from head to toe. As she desperately tries to fight back, both her endurance and magic drain away, leaving her in a desperate situation with no escape.

Yet again, trouble finds Yuki and disrupts his idyllic life! Yuki’s boisterous new life as a demon lord in a fantasy world continues. One day, while he and his pets are hunting monsters to refill the dungeon’s rapidly depleting coffers, he abruptly runs into Lew’s father. “Give me back my daughter!” the man roars angrily, and misunderstandings lead to him challenging Yuki to a duel. How is our antihero supposed to deal with this hairy development?! In the meantime, Nell, Yuki’s second wife, decides to return to the royal capital as part of her duties as a hero. Yuki means to accompany her as her bodyguard, but an unexpected incident disrupts that plan—someone sets a wild stampede in motion against them. On top of that, a sinister presence lurks in the shadows, intent on targeting Nell. Can the two put a stop to these threats?!

This time around, a plot to ruin Nell gets in the way of Yuki’s ideal life! Yuki’s exciting second life as a demon lord in another world continues. He and Nell arrive safely at Alisia’s royal capital, where they immediately set off to explain her situation to the king. There, they learn of a nefarious scheme designed to undermine Nell’s role as the country’s hero. Determined to find and crush those intent on hurting his precious wife, Yuki uses all the skills and tools at his disposal to gather information. And when he learns that the mastermind is planning to attack at the royal ball, Yuki, with the king on his side, makes his move to settle things once and for all!

Reborn in another world as a demon lord, Yuki is off on another adventure. This time, he’s taking part in a dungeon conquest at Nell’s invitation. He heads to their destination with half a mind to sightsee when he spies a ghost ship floating in the ocean! With his new mace in hand, he and his allies fight off the wraiths, skeletons, and other varieties of undead monsters infesting the ship. And then, they finally come face-to-face with the enemy demon lord. But their opponent is a powerful dark magic user capable of launching attacks that inflict debuffs?! In order to defeat the enemy demon lord, Yuki will have to unleash his secret, explosive spirit magic!

Reborn in another world as a demon lord, Yuki is managing his newly—and accidentally—acquired phantom ship dungeon. At the same time, he’s steadily working on expanding and strengthening his existing territory. Then, one day, he thinks it’s about time for him to stop neglecting his duties as the Dragon King, so he decides to visit the Dragon Hamlet and introduce himself to its residents. He and Lefi take to the skies to get there, but on the way, they encounter a massive airship under attack by monsters. After helping the humans operating it, they resume their journey and finally arrive in the Dragon Hamlet, where they’re greeted by the elders. He pours his magic into a stela to carve his name into the dragons’ annals as their newest Dragon King, but then...

Reborn as a demon lord in another world, Yuki is currently helping Lefi think of ways to fight now that she can’t revert to her original dragon form anymore. After a bit of brainstorming, she succeeds in Dragonizing herself by covering her entire body in scales, thus strengthening her human form! With that task complete, all that’s left for her to do is train. Suddenly, however, Yuki receives a distress signal from Nell. He rushes to her side, only to find the Elvish Enclave under attack by the fiends, who declare war on the alliance of elves, demons, and humans! At long last, war breaks out between several nations! Yuki joins the battle in order to protect his family in the dungeon, but what awaits him and the others?!

The war between the Raceless Allies and the Human-Demon Axis has ended, and Yuki finds himself the reluctant owner of an entire empire. Since the other leaders have things well in hand, he takes a breather and heads home to the dungeon, where he suggests to his family that they go on a trip. Their destination? Leila’s hometown, where the ovine race lives! So off they go on an airship, the visit both a homecoming for Leila and a reunion with her wise teacher, Eldgalia! On top of all that, Yuki has a wedding to plan with Lew because her father’s one-year deadline for them is coming up. Meeting the parents? Nope, meeting the whole werewolf clan! And then Lefi makes a shocking announcement too?! Not to mention the unexpected weapon Eldgalia forces on him... Yuki’s second life as a demon lord is shaping up to be anything but chill!