Umibozu appears to be a giant aquatic humanoid creature with inky black skin and a pair of large, glowing white eyes. However, according to Japanese mythology, Umibozu are spirits of drowned priests, cast into the sea by angry villagers. These priests were then transformed into Umibozu due to the horrible nature of their deaths. Due to encounters with an Umibozu being rare and almost always fatal, it's likely their true origins will forever remain a mystery.