The High Japester was the ruler of the Geramons of the planet Beedle.
When ruins were found on Beedle, both the Knyy'ds and the Mystic Wizards claimed possession, so representatives from both races, as well as an arbiter and Bernice Summerfield, came to Beedle. It was a hoax, however, as the High Japester wanted victims for his practical jokes. When he was found out, he tried to leave the planet, but Demjely smuggled a nuclear bomb aboard his ship, and became the new High Japester. (PROSE: Beedlemania)