Average 37-year-old Minami Satoru dies and is reincarnated as the most unremarkable creature imaginable-a slime.

The story takes place between the first and second seasons, where Rimuru confronts the swirling conspiracies in the Coleus kingdom.

A long-running conspiracy is swirling over a mysterious power wielded by the Queen in Raja, a small country west of Tempest. When a slime who evolved into a Demon Lord named Rimuru Tempest crosses paths with Hiiro, a survivor of the Ogre race, an incredible adventure packed with new characters begins. The power of bonds will be put to the test!

In this spinoff series, Rimuru gets his hands on a notebook and decides to compose a record of his many adventures. But where to begin?