One day, Shuna and Shion are fighting over Rimurus squishy slime body as usual. Rimuru figures that giving them each a body double of himself would solve the conflict, but when he imagines some of his other friends asking him to do the same for them, he quickly drops that plan. Then he comes up with the idea to make a cushion in the shape of his slime form. He travels around Tempest to see if his friends know of any good materials he can use, and he learns that a special type of sand found along a lake shore in the forest is exactly what hes looking for. So he sets out to collect some sand... but a monster is waiting for him by the lake! Whats more, Milim hears about his plan for a picnic and comes racing down from the sky!

(Source: Crunchyroll)