How to Spend a Certain Vacation

How to Spend a Certain Vacation (とある休暇の過ごし方) is a side story written by Fuse that started weekly publication on on February 20, 2023 to celebrate Tensura's 10 year anniversary. Serialization into manga form began on July 26 of the same year, in 's September 2023 issue, with  serving as the story's mangaka.

Plot
Rimuru, Veldora, and Hinata set out on a quest to seek the Magic Tower at the suggestion of Luminous after they get into a heated discussion about recreating the 'Beast Magic' of. The party of three makes a brief stop at the nearby Kingdom of Malukshure while their enthusiasm for developing new magic only continues to rise.

Novel Chapters

 * Paid Vacation (有給休暇)
 * The City of Sages (賢人都市)
 * Invitation to the Evening Party (夜会への招待)
 * Events of the Evening Party (夜会での顛末)
 * Behind the Scenes (舞台裏の事情)
 * The Scheming Mastermind (策謀する黒幕)
 * Relief Efforts (救助活動)
 * Whereabouts of Negotiation (交渉の行方)
 * Rimuru, Rampage (リムル、暴走)
 * Settlement and New Era (決着と新時代)

Manga Chapters

 * Prologue - Luminous' Invitation (ルミナスの招待状)
 * Chapter 1 - The City of Sages I (賢人都市Ⅰ)
 * Chapter 2 - The City of Sages II (賢人都市Ⅱ)
 * Chapter 3 - Private Discussion (御内密の話)
 * Chapter 4 - Invitation to the Evening Party (夜会への正体)