The Dragon Monster appeared in the episode Down 'n' Dirty.
He is a dark green monster with light purple fur and 2 webbed antennae. He has large nostrils for sucking up and a large mouth with red lips and pointed white teeth to breathe fire, as his name is derived. He makes a roar similar to that of a person snoring or a pig oinking. He looks almost like a dinosaur version of Fuzzy Lumpkins.
He rises from the water and sucks Buttercup in his nose, then blows her out upon smelling her. This ends up motivating Buttercup to finally take a bath.
The Dragon Monster is voiced by Frank Welker.
The Dragon Monster in Sand Hassle
The Dragon Monster reappeared in a book called Sand Hassle, but is scaly with green spikes and antennae.