Goowee

Goowee (ぬるりん, Nururin) are a species of air-breathing, fishlike creatures covered in a thick slime that are native to the Demon World. They were found and identified in the forest outside of Shelter B06-32 by Thoma and Lannion. They are not given an official scientific name, and are instead named after their "goo-ey" texture by Thoma and Lannion.

They are shown crawling along the edges of tree bark in the Demon Forest, which is assumed to be their natural habitat.

After struggling to catch them using their hands, the children take them back to the bunker to eat. They draw sticks to see who will test them for safety. Nat draws the losing stick, but is then replaced by Ray, Thoma, and Lannion upon throwing a tantrum regarding it.

Goowee apparently have quite a nice taste, as the children begin to quickly eat more of them than they are allotted. They contain no dangerous properties and are safe for human consumption.