Diablo, Rem, and Shera have arrived at the Bridge of Ulug only to discover that an army of Fallen are marching towards Faltra! This should be no problem for a powerful Demon Lord like Diablo...except that Diablo is actually Takuma, a video game addict who's in way over his head. Will Diablo's stats hold up in a real-life battle?

After being summoned to another world similar to the game he used to play, Diablo lives a tumultuous life in this new world after he finds himself the unwitting master of Rem the Pantherian and Shera the Elf; and now, even the Demon Lord-turned-young-girl Klem obeys him! One day, Diablo ends up rescuing a holy woman who was being pursued by a Paladin, and she turns out to be the most important person in the Church. Befriending her, Diablo and the others act as her escorts until they reach Zircon Tower deep in the Demon Lord's territory. After arriving in a new town, more difficulties arise, ultimately culminating in the appearance of a gargantuan monster attacking them! Is the self-proclaimed Demon Lord becoming a guardian deity for a follower of the Gods!? This is the fourth volume of the adventure of an earth-shakingly powerful Demon Lord (or at least someone who acts like one) taking on another world!

'" Takuma was just another awkward gamer, but a twist of fate sees him summoned to another world--in the body of a demon lord! And no one''s more terrified of the prospect than Takuma himself. He may have power, but he''s in way over his head. So he decides to pretend to be the monster he looks like, and accidentally winds up with a pair of gorgeous slaves: a voluptuous elf and cat girl. It''s not what any of them wanted, but they''ll have to figure out how to work together if they want to survive! "'

In the MMORPG Cross Reverie, Takuma Sakamoto is so powerful that he is lauded as the "Demon Lord" by other players. One day, he is summoned to a world outside his own-- but with the same appearance he had in the game! There, he meets two girls who both proclaim themselves to be his Summoner. They perform an Enslavement Ritual to turn him into their Summon... but that's when Takuma's passive ability activates! Instead, it is the girls who become enslaved! Though Takuma may be the strongest Sorcerer there is, he has no idea how to talk with other people. It is here he makes his choice: to act based on his persona from the game! "Amazing? But of course... I am Diablo, the being known and feared as the Demon Lord!" So begins a tale of adventure with an earth-shakingly powerful Demon Lord (or at least someone who acts like one) taking on another world!

The High Priest Lumachina has been afflicted with a curse, and Diablo's only way of saving her is by reclaiming an item he once obtained in the game Cross Reverie. His next challenge: a dungeon that has claimed the lives of many brave adventurers... But his confidence isn’t misplaced, for it was he who designed that very dungeon! Even when facing off against a supreme dragon, Diablo never falters, just like a true Demon Lord! "Heh, you think yourself a God with a mere level of 140? Don't make me laugh, you overgrown newt!" At the same time, a Fallen heralding the return of the Demon Lord appears in Zircon Tower...?! Will Diablo be able to conquer the dungeon he himself created to retrieve the cure and make it back to defend Zircon Tower in time?! This is the fifth volume of the adventure of an earth-shakingly powerful Demon Lord (or at least someone who acts like one) taking on another world!

The former prime minister, Noah Gibun, is revealed to be an outsider. Like Diablo, she's a player of the MMORPG who came to this world. In order to defeat the Emperor and his overwhelming power, Noah recruits Diablo and the young Demon Lord Klem into her ranks. At first, Diablo's fear of social interaction made him refuse, but eventually... “I admit it. You are the leader.” “Thank you, Diablo. I will do everything to answer the trust you’ve placed in me.” Diablo finally decides to fight in a party...?! This is the fourteenth volume of the adventures of an earth-shakingly powerful Demon Lord (or at least someone who acts like one) taking on another world!