Harold is a red-orange fish with chubby cheeks who makes several cameo appearances throughout the series, starting with the episode "Ripped Pants."
He is a red-orange fish with light orange fins, light orange eyelids, and chubby cheeks. He wears light blue swim trunks that sometimes have green flowers on them.
He first appears in the episode "Ripped Pants," roasting and eating marshmallows in Goo Lagoon when SpongeBob asks him if he could borrow some, to which he nods yes. He is seen again in "Hooky" as a cameo, saying his sandwich is a fried boot.
He appears again in "Tutor Sauce," in which he makes a cameo appearance with Squidward, whacking him with a spatula for seemingly no reason.
In "SpongeBob's Place," he is one of the Bikini Bottomites chanting "SpongeBob's Place!" after Squidward suggests to Mr. Krabs that he changes the name of the restaurant.
He appears again in "Trident Trouble," when he wishes the grass would grow, and when SpongeBob uses the trident to make it grow, the grass chases after Harold with his lawnmower. He is later seen mowing the grass again near the end of the episode.