Beezle has a mostly black head, with green cat eyes, a black nose, and yellow teeth. One tooth on the left side sticks out of his jaw. The sides of his head as well as the insides of his ears are orange. Three strands of hair lie on each of his ears. He has an orange body, black legs, black paws, and a black tail. His claws are yellow. He wears a black leather collar with a silver buckle and a gold nameplate bearing his name (He never actually introduces himself, Garfield gets his name from his coller).
However, when there is a full moon, Beezle transforms into a beast several times Garfield's size with "burning red eyes, long, pointed ears, glistening teeth, and long, jagged claws." His nose also turns red like his eyes and the sticking-out tooth seems to have disappeared.
StoryBeezle is the pet cat of Peter Wary and appears on the windowsill staring at the rising full moon. After Jon, Garfield, and Odie check into Wary Inn, Garfield meets Beezle and the two cats have a brief conversation about the rumored beast, Beezle claiming that "He's never quite himself when there's a full moon." (Garfield most likely took this as meaning that Beezle's scared of the beast, but it is revealed later that he meant that he is the beast.)
Garfield eventually leaves Beezle and goes to bed. However, he finds that he is hungry. After a quick battle of fear vs. stomach, Garfield decides to grab a snack real quick. He is just grabbing a banana cream pie when the beast appears behind him, a bit of gold gleaming at its neck area. Before he is eaten, Garfield throws the pie into the beast's face and hurries back to bed. The next morning, as the Arbuckle's car is driving away, Garfield sees Beezle staring hungrily at him from the parlor window, the sunlight twinkling on the golden nameplate on his neck.
Whether or not Garfield guessed the truth is questionable, as the segment ends here. But the readers can connect the twinkling on the beast's neck to Beezle's shiny nameplate and figure out that Beezle is really the beast.
Beezle is a sly, cunning, and evil cat, being a normal pet of Peter Wary and turning into a beast when there's a full moon. Despite this, Beezle most likely has a loving pet-owner attachment to Wary, as Wary probably knows of Beezle's transformations and yet the cat has never tried to eat him, considering they live in the same building.
Beezle is also a cannibal, cats being "tempting treats" for his beast form. However, his cat-eating obsession might extend to his normal form as well, as he was staring hungrily at Garfield as he was leaving. In addition, as indirectly revealed by himself, Beezle has eaten at least one bulldog before.