Rimuru and the five children enter the Labyrinth, only to be attacked by a Golem controlled by a mischievous spirit, Ramiris. Rimuru destroys it, forcing Ramiris out and her revealing the doubtful information of her being the Fairy Queen and a Demon Lord. Rimuru explains the situation with the kids and thus encourages each of them to call for a spirit to help stabilize their condition.
Following a tip from a waitress, Rimuru Tempest and his class, Kenya Misaki, Alice Rondo, Gale Gibson, Ryouta Sekiguchi, and Chloe O’Bell plus Ranga arrive in Ulgrasia Republic's national park where they enter the Dwelling of the Spirit. Thanks to Rimuru's mental map navigating the labyrinth is surprisingly easy in spite of numerous traps designed to confuse their sense of direction.
The group hears a voice talking to them which leads them to a Golem who is apparently their 'first test.' After considering a couple of options Rimuru ops to simply incapacitate his enemy with Steel Silk and finish it off with Dark Flame. After taking a moment to accept the applause of his students Rimuru spots the figure the sicced the golem on them and threatens her with the same fate if she doesn't reveal herself.
A terrified fairy introduces herself as Demon Lord Ramiris of the Labyrinth. Rimuru doesn't believe her, having already met the likes of Milim Nava and Carrion and concluded that she is far too weak to be a Demon Lord. Based on what Rimuru has said Ramiris also realizes that Rimuru is the slime that took control over the Jura Forest, leading to Rimuru to reveal to his students his slime form.
Breaking for the time being Ramiris, while eating the cookies Rimuru prepared for his students, explains that her Elemental Colossus as she calls it is a sophisticated creation of dwarf engineering that she modified using a combination of spirits to make it work, leading to Rimuru to also realize that the Golem was Vesta's failed magi-soldier project.
Rimuru also comes to the understanding that Ramiris possesses the skill set he needs to fix his students' rampant magical power and thus asks for her help and in exchange, he will build her a new golem. Thus Rimuru asks her to introduce him to the Queen of Spirits, to which Ramiris also claims, having originally been the Queen of Spirits but then fell from grace and became a Demon Lord.
While on the subject, Ramiris also mentions that another Demon Lord, Leon Cromwell, was originally a Hero. He had originally come to Ramiris trying to summon a specific individual, but when that failed he instead summoned Ifrit and Ramiris had no other choice but to give him the divine spirit's blessing. Ramiris leads Rimuru to the Dwelling of the spirits where she explains that they can summon existing high-level spirits or make new ones out of raw magical power.
With this, Rimuru promises that he will resolve Shizue Izawa's lingering regrets.
|Episode 1 • Episode 2 • Episode 3 • Episode 4 • Episode 5 • Episode 6 • Episode 7 • Episode 8 • Episode 9 • Episode 10 • Episode 11 • Episode 12 • Episode 13 • Episode 14 • Episode 15 • Episode 16 • Episode 17 • Episode 18 • Episode 19 • Episode 20 • Episode 21 • Episode 22 • Episode 23 • Episode 24 • Episode 24.5|
|OAD 1 • OAD 2 • OAD 3 • OAD 4 • OAD 5|
|Demon Lord Attack arc||Human-Monster Interaction arc||Demon Lord Awakening arc|
|40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 54 | 55|
|20 | 21 | 22 | 23|