Whisper serves as the ghost butler to Keita, the main human character. He is a Yo-kai and a central member of Keita's core group alongside other Yo-kai like Jibanyan and Komasan. His first encounter with Keita occurs in the television anime's premiere episode, later integrated into the compilation film "Yo-kai Watch ♪ Keita to Orecchi no Deiai-hen da Nyan ♪" with additional scenes. This film chronicles their initial meeting, defining Whisper's role as Keita's spectral attendant and companion.