Keroppi gets blamed for something he didn't do, runs home crying, and gets struck by lightning that throws him into the exact fantasy world from the movie he was watching, except now the stakes are real and the cowardly prince beside him needs to learn what courage actually costs. This is a show about two characters who are afraid, who have every reason to stay afraid, and who choose to move forward anyway. By the end, you understand why a scared frog and a scared prince had to meet in another world to learn they weren't alone.

Keroppi's day takes a dark turn when he gets blamed for mischief other people caused during a movie. He runs home in tears, only to be struck by lightning that carries him into another world, just like the one in the film. There he meets a cowardly prince. Together, Keroppi and the prince set out on an adventure that teaches them about courage and about standing up for themselves. The result is a gentle, single-episode fantasy OVA built around a young hero finding his nerve.