Monster Federation and Holy Empire

Monster Federation and The Holy Empire (魔国連邦と神聖法皇国) is the eighty-ninth chapter of the manga adaptation of That Time I Got Reincarnated as a Slime.

Summary
After Edmaris saw the peaceful city of Tempest, he carefully reflects on the situation and came to the conclusion that the Kingdom of Falmuth being a vassal state to Rimuru's country is not a bad future. However, the nobles of the kingdom refuse the idea of being colonized by monsters, and thus continued with their arguments and clashing of opinions. Edmaris calms them down and starts sharing his thoughts about the war; he starts with how he is regretful of his actions and should've listened to his advisors. He threw away his pride as a king and started thinking for his people's sake and not of his own greed. His advisors and subjects were dumbfounded by this sudden change of heart.

Just as they were about to discuss which of the three options to pursue (pay war reparations, pledge vassalage, continue the war), a soldier forces his way in and interrupts the meeting. The soldier brought news from the Free Guild about major changes in the circle of the Demon Lords after a recent Walpurgis ended. The nobles were surprised by the news that the "Marionette Master" is dead, the "Beast Master" and "Sky Queen" relinquished their titles as Demon Lords and became subordinates of the "Tyrant of Destruction" and the council would henceforth be called 'Octagram'. They wondered why the numbers didn't add up and why there were eight Demon Lords instead of seven.

Everyone at the meeting was bewildered after hearing that the Overseer of the Great Forest of Jura was responsible for the defeat of the "Marionette Master" and joined the ranks of the Demon Lords. He was dubbed "Rising Star" to the public. With this, all who were present in the meeting were now convinced that they don't stand a change against the Demon Lord Rimuru, and that went doubly so with the Storm Dragon he has allied himself with. Continuing the war would be a pointless endeavor, the nobles cannot stand the idea of being colonized; which only leaves them the option of paying the war reparations. Observing the end of this discussion, the king unexpectedly nominated his half-brother Edward as his successor. The brother was overjoyed by this but he hid his emotional state with a graceful bow. Razen sees the progress of Diablo's scheme as satisfactory for now.

Shuna and Souei were the first to return from Clayman's castle. Rimuru is overwhelmed to the point he was speechless because an undead skeleton along with its minions started worshiping him like a god and asked Souei to take them to the cave before they wither under the sunlight. Hakurou is currently working with Geld in investigating Clayman's castle, dividing up the war spoils, and handling of the prisoners of war. Diablo returned to Tempest after he was successful with his exploits and reported everything that happened to Rimuru. He presents the partial payment for the war reparations. They start to discuss the current events inside Falmuth anticipated that a civil war will happen soon. Rimuru wants to settle the issue of Tempest and the Western Holy Church without a bloodbath so he sends Rayhiem to deliver a message. Gabil and the Beastmen returned to Tempest several days later, bringing the prisoners. Gabiru hands over a letter from Milim. She wants Rimuru to teach them the essence of cooking since all of her worshippers eat their food raw.

A month after the Walpurgis has passed, Tempest has become more livelier now that the population increased. Geld and Rimuru are drinking together while discussing Geld's worry about the handling of the newcomers. He gets fed up of the uncooperativeness of the prisoners. He was stressed because the High Orc race never had a discord amongst themselves which made them synchronized and worked together in harmony, the opposite of the prisoners. The next day, Rimuru gathered all of his officials for a meeting. His first news was the start his reign as a Demon Lord which everyone already knew, the second was that all of the entirety of Jura is his territory. Rimuru decides to have a festival so as to refresh their minds from all the hectic events that happened.

The chapter ends with Hinata starting a meeting with the Ten Great Saints to discuss the recent resurrection of Veldora and Rimuru's emergence as a newborn Demon Lord.

Adaptation Notes
Information to be added later on.

Trivia

 * The other name for Octagram is "Eight-Star Demon Lords" and Rimuru's title here is "Rising Star" which is a bit on the nose here. (since he is the newcomer Demon Lord)