That Time I Got Reincarnated as a Slime

OAV 1 is about Rimiru wants to be able have a nap, which is achieved by visiting Vesta and getting some pills. Though what happens afterward makes it interesting. OAV 2 has Rimuru deciding to make duplicate cushions to reduce village tension. The problem is to find something to fill the cushions that replicate a comfy feel. This leads on a dangerous mission to a mysterious lake. OAVs 3-5 continues right after the first series with Rimuru and the Shizu-san's former students at Freedom Academy getting involved in Outdoor Training that includes a journey overland to the town of Guratol and a cave encounter there.