Yo-Kai Watch began as a Japanese role-playing game series developed by Level-5, first released in Japan in 2013, and soon expanded into a popular anime television series about a boy who can see mischievous spirits called yokai. Its cheerful theme music became closely linked to the franchise's playful world, and clips of it spread through fan edits, gaming videos and social media as viewers shared their nostalgia for the show. It remains in use because the tune is instantly recognisable to fans and works as a quick shorthand for a supernatural surprise.