King Koo Koo, a near microscopic king who has a part of him expand every time he laughs at someone else. He finds that the curious little trio that has been brought to him do a good job of making him expand overall when they subjected to Sir Leonard Looney's gags. Before the King can find a better use for them, the Raggedys and the Camel escape out an exit, leaving King Koo Koo to shrink back down to his regular size. King Koo Koo then decides that the Raggedies are perfect and will be just what he needs to accomplish what he has been waiting for his entire life - his "Last Laugh." He calls up his cohort Gazooks, a giant, green, inner tube-like sea creature with a massive array of arms and discusses his plans. Later On, King Koo Koo, who had been eavesdropping on Raggedy Ann and Babette, has them quickly subjected to the same tickle-torture, while Queasy rockets towards the massive balloon that King Koo Koo has become. King Koo Koo, who now dominates the horizon, celebrates his enormous size and finally getting his last laugh while Queasy collides into King Koo Koo beak-first, like a pin into a balloon, causing him to explode.
He was voiced by Marty Brill.