Summer has come to Tempest. When he learns that summers here weren't always this hot, Rimuru begins to fear that the change was his fault. Shuna and Shion have their own unique way to keep cool, and Rimuru tries to think up some fun summer activities... but bug-catching turns into bug-hunting when the bug he's after turns out to be enormous, and a game of shooting water pistols gets out of hand when Rimuru himself becomes a water cannon. With everything on a completely different scale in Jura, every activity he tries turns into pure chaos! And Rimuru has no idea that he himself is the ideal cold pack...