Rikiya Sudo

Rikiya is a 12-year-old boy with a scary look in his eyes. Both of his parents are currently in prison. He tells Kokoro that adults on the island cannot be trusted, that there is some secret they want to hide, and that they dispose of any kid who discovers that. He says that the school is just a coverup for their search for gold.
During one rainy night, he goes off alone into a restricted area to search for the gold himself, but meets his inevitable fate.
He actually falls from a cliff out of surprise when a dog that he used to feed jumped at him playfully.