Sabikui Bisco Season 1 Episode 5

Children's Fortress

On their way to Akita, Bisco and Milo pass by the sea of Calbero and arrive at a desolate town under threat from the deadly creatures, Flying Blowfish. A town that's also full of children and devoid of adults. Meanwhile, Pawoo encounters a mysterious couple living in some ruins as she pursues the others.