Survival in Another World with My Mistress! Novel Volume 8 was written by Ryuto with illustrations by Yappen.

Having taken back the Kingdom of Merinard, Kosuke and his allies get busy with restoration efforts. But while they're hard at work, news comes in from the north that the Principality of Diieharte and the Kingdom of Tigris are preparing for war. A special task force is formed around Kosuke and Ira, with Shemel, Bela, and Tozume as backup, and together they head off to defend the borders of their reclaimed kingdom!