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!

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!

For the first time since waking up in his favorite MMO, Diablo is up against an opponent that's actually as strong as he is! Galford is a mighty warrior and the governor of Faltra, but instead of keeping the peace, he's been trying to start a war with the elf kingdom! If Diablo can't defeat Galford in battle, then the whole world's in trouble!

With the threat of Krebskulm's resurrection safely suppressed (for now, at least), Diablo and his companions hope to enjoy a little peace and quiet. But a mysterious young woman has appeared in the forest outside Faltra, on the run from another Paladin. When Diablo stumbles upon her, it opens the door to a new adventure!

Shortly after Kelvin’s promotion to the coveted position of Rank S adventurer, the militaristic country of Trycen declared war on the entire Eastern Continent. In addition to launching an invasion of its neighboring countries, their infamous Dragon Knight Order is now closing in on Parth, led by Crown Prince Azgrad himself. The only thing standing between this dreadful host of warriors and ancient dragons — exceptionally powerful members of their mighty race — and the City of Peace is the Summoner’s determined companions and allies, who have been given the task of buying time until reinforcements arrive. At the same time, Tristan Faaze, the general of the Magic Knight Order, is hatching a terrible plot within Trycen itself, targeting Shutola, the princess and general of the Black Ops, who weeps for her country’s fate. Come along for the ride as this black-clad Grim Reaper and his battle junkie friends clash with the Demon Lord in the fifth volume of this epic journey!