After a fatal assault, virgin salaryman Mikami reincarnates as a slime monster. While acclimating to his new body, he hears the voice of a dragon.
Mikami receives a new name from Veldora. The two buddies come up with a plan to break Veldora's seal but this has unexpected political repercussions.
Rimuru prepares the goblins for the canine assault. His fighting abilities prove effective but this soon leads to some unanticipated challenges.
Rimuru and his party arrive at Dwargon, the kingdom of dwarves. But before they can enter, he gets into a fight with some thugs and is thrown in jail.
Rimuru and the dwarves celebrate their success, but they are soon interrupted by Kaijin's client, who does something that makes Kaijin see red.
The three adventurers go to investigate the forest and are joined by a masked summoner named Shizu, who Rimuru recognizes from somewhere else.
Shizu recalls how she met Leon, the source of her powers and suffering. While preparing to head off, she tells Rimuru the reason behind her wandering.
Shizu tells Rimuru about the mysterious hero who helped her escape Leon's clutches. Then, sensing her end is near, asks him for one final favor.
While Rimuru practices with his new abilities, a group of ogres assault his goblins, claiming that he's been manipulating orcs to attack them.
Rimuru learns that the orcs who attacked were led by a masked figure and he proposes a temporary alliance with the ogres until their foe is defeated.
Rimuru's village prospers with its new ogres, but Gabiru soon shows up with an intimidating proposal. Later, a dryad makes a request of Rimuru.
The dryad Teyni explains how the Orc Lord uses a pernicious skill to wreak havoc and begs Rimuru to help. He accepts but realizes he needs allies.
On the way to finalize the alliance, Rimuru finds Gabiru's sister, who appraises them of the situation. Meanwhile, the Lizardmen are in big trouble.
Gelmud suddenly appears and shocks everyone by revealing his sinister plot. Later, the Orc Lord does something that surprises them even more.
At the meeting between representatives of the Orcs, Goblins and Lizardmen, Rimuru must ensure his proposal is acceptable to all competing groups.
Gazel delivers Vesta to Kaijin and Rimuru. Vesta begs for forgiveness and asks for the chance to apply his research skills to Rimuru's benefit.
Phobio, one of Carrion's beastkeepers, comes to Tempest with belligerent intentions but Milim deals with him. Rimuru learns about the demon lords.
Two of Clayman's minions convince Phobio to make a pernicious decision. Tyra warns Rimuru that a powerful being threatens their destruction.
Although Rimuru's ragtag group of defenders is able to take on the Megalodons without too much difficulty, Charybdis proves to be a more powerful foe.
Rimiru has a dream about Shizu and decides to travel to Ingrassia with Ranga to see her and her students, who he learns are in grave danger.
Rimuru shows Shizu's students what real power looks like. Later, he visits Teryni to ask how the spirits might help ensure the students' survival.
Rimura and his allies enter the Dwelling of the Spirit to find a way to save the kids. But they soon encounter a magical golem that blocks their way.
Rimuru turns a number of lesser spirits to his companions' advantage. Sensing danger, Ramaris tries to stop a strange being from possessing Chloe.
Long before Rimuru's arrival, Shizu travels to the Kingdom of Flitwood to deal with a demonic threat. But the task proves to be insidiously complex.
In Tempest, Rimuru sends delegates to Eurazania as part of the pact between the two nations. He then prepares to welcome Eurazania's diplomats.
After an intense greeting, Rimuru welcomes the Eurazania delegation with a modest dinner party. The Tempest diplomats report back with their findings.
Rimuru and King Gazel discuss trade before officially declaring friendly relations. Later, Rimuru and the goblins enjoy the Dwargon nightlife.
Youm gives his new wizard companion a tour of Tempest. In Falmuth, the king discusses how to handle the growing threat of Tempest with his advisers.
As the town prepares to celebrate Rimuru's return, Clayman contacts Mjurran. Meanwhile, the three otherworlders from Falmuth raise a ruckus.
On his way back home, Rimuru is suddenly trapped within a strange barrier. The otherworlders continue to cause chaos in the streets of Tempest.
After avoiding Hinata's devastating spell, Rimuru regroups with some of his subordinates and tries to find a way to remove the barrier around Tempest.
In the aftermath of the invasion, Rimuru visits the wounded and receives some awful news. Later, Eren shares a story that gives him a glimmer of hope.
Determined to become a demon lord to revive Shion and repel the approaching Falmuth army, Rimuru plans a military strategy with his companions.
Tempest's forces launch a series of ruthless surprise attacks on Falmuth's military encampments. As Geld fights Shogo, Hakuro duels with Kyoya.
As the Falmuth soldiers fall to Rimuru's terrifying attacks, their king desperately attempts to bargain with him. But Rimuru refuses to show mercy.
Rimuru awakens to discover that his evolution was a success. Three Eurazania warriors tell him of a recent tragedy that occurred in their kingdom.
The residents of Tempest celebrate Veldora's return with a feast. The next day, Rimuru informs his council of his intent to take on Clayman.
Laplace reports his findings on the Western Holy Church to Yuuki and Kazalim. Rimuru introduces Veldora to the gathered leaders of the other nations.
Rimuru describes his elaborate plan to announce his ascension as a demon lord and make Youm the new king of Falmuth, but King Gazel has his doubts.
Ramiris tells Rimuru that Clayman has set in motion an event that could spell the end of Tempest. Shion reports what she learned from the prisoners.
Rimuru devises a way to rescue the people of Eurazania and put a stop to Clayman's plans. He then decides to attend Walpurgis with Shion and Ranga.
Impressed by Rimuru's tactics, Clayman strengthens his resolve to defeat him. Ahead of Walpurgis, demon lords Leon and Guy discuss Veldora's return.
As he prepares to attend Walpurgis, Rimuru approves a plan to attack Clayman's castle. The Tempest forces led by Benimaru ambush Clayman's army.
Gabiru and Suphia take on Middray, one of Milim's faithful followers. Meanwhile, Albis shows no fear as she fights against Yamza and his doppelgänger.
Rimuru finally leaves to join the demon lords at the banquet. On the way to Clayman's castle, Shuna's group is suddenly surrounded by a skeleton army.
Clayman begins the banquet by denouncing Rimuru, who rebuts his sordid claims with solid evidence before engaging him in a battle to prove his status.
Grossly outmatched by Rimuru and his friends, a desperate Clayman unleashes his demon lord form before making a deadly last-ditch request of Milim.
Rimuru inflicts a harsh punishment when Clayman refuses to reveal the name of the true mastermind. The demon lords share what they know about Kazalim.
Rimuru is tasked with investigating a royal succession crisis in the Kingdom of Coleus to help the Free Guild determine which heir it should support.
Aslan suddenly visits the palace and tells Rimuru that Gustav may be manipulating the kingdom. Later, Zenobia implores Rimuru to save her brothers.
After the conspiracy is uncovered, Rimuru and the princes get trapped inside a barrier with Carl. Outside the barrier, a surprising battle unfolds.
Following Clayman's defeat, Rimuru returns to Tempest. There, Diablo tells him how his devilish strategy for taking down Falmuth is unfolding.
Saddened by the loss of Clayman, Yuuki's group plans its next move against the Demon Lord Rimuru. Luminus, who mourns Roy's death, does the same.
Now that Tempest's territory contains all of Jura Forest, Rimuru decides to hold a festival in order to welcome all its new residents at once.
Amid concerns about monster attacks ahead of the festival, Vesta and Kaijin devise a way to secure safety on the roads. Rimuru gives Geld a new task.