Summary: A boy goes to a beach to find bottle tops, but instead, he discovers a bizarre looking creature. The boy, thinking that the creature is lost, tries to find the owner or where it belongs. Though nobody else seem to notice the creature's existence. Then, the boy feels sorry for the creature and looks for its home.
What is the "Lost Thing"?: Similar to Mermaid by Osamu Tezuka, I think this story tells us about the power of imagination and how we lose it as we grow older, and the loneliness of being able to see what nobody else could see.