Teru Teru Bozu is a traditional Japanese children's song first published in 1921, with lyrics by Kyoson Asahara and music by Shinpei Nakayama. It takes its name from the small white paper doll hung outside homes to wish for sunny weather, a folk custom still recognised across Japan. The song has stayed in school songbooks and popular memory for more than a century, and in recent years online creators have revived it in rainy-day videos, nostalgic edits and horror-themed clips, where its innocent melody takes on a much darker tone.