Stewart: What's a "cropsy"?
Marsupilami: What's a cropsy?! Only the biggest, smelliest, ugliest creature to ever hit the jungle... present company aside, Moe.
This character's name and reputation is loosely based on the 1980's movies, which in turn are based off an urban legend (basicly, the city-folk version of the boogeyman) but dispite being a large sloth with a moose-like head, Cropsy is actually a nice guy, who's picked on for his size, and is bummed out by the "nasty stories" locals make up about him, and Mars admits he's heard a few of them (in fact, that long-tailed kidder recited one to Maurice and Stewart the night before and pushed the envelope with a "joke" based on Cropsy being a monster moments before the real one shown up). In turn, Cropsy probably heard a few rumors of the polka-dotted prankster himself, though he thinks the tiny creature's name is "Houba" via the catchphrase. As they properly introduced, Cropsy was corrected that his new friend's name is Marsupilami, and Mars can obviously relate to Cropsy's loneliness from being "totally unique". As a surprise for Maurice and Stewart, Mars introduces Cropsy as though a celebrity, and Cropsy, after apologising for the startle, tells a real ghost story about a shadow that came out of a camp fire (which appeared, frightening Cropsy, Maurice, and Stewart... but only because Mars invited a mouse.)
Cropsy is a one-episode wonder in "Cropsy-Turvy", but since he appeared close to the end of the season, he would've made another appearance if the show had a season 2.