That Time I Got Reincarnated as a Slime manga volume 21 features story by Fuse with illustrations by Taiki Kawakami.

A Reunion on the Battlefield: Rimuru and Hinata hoped to avoid fighting, but that seems inevitable now. Curiously, each of them believes the other is the aggressor. A third party is clearly pulling the strings, pushing both sides toward open war, and all signs point to the Seven Days Clergy. However, Rimuru is determined to keep the peace, ordering his subjects not to kill. Can the Demon Lord and the leader of the Ten Great Saints uncover the truth before it’s too late? This may require intervention from the most unlikely source...