If you were looking for the article about the whale, then see Don the Whale.
If you were looking for the article about the food critic, then see Don Snapper.
If you were looking for the article about the surfer, then see Grubby Grouper.
WARNING! This page may contain spoilers of an episode that is unaired or has yet to air in the United States. Do not continue reading if you wish not to be spoiled.
Don Grouper is an ad executive who will appear in the upcoming episode "Goodbye Krusty Krab."
According to Nickelodeon, he is "a charismatic head ad executive of the ad agency Grouper, Goby & Koi."
His "sharp mind and devastating charm make him an irresistible force. When Don's in the room, everyone laps up his words like overpriced organic honey," Nickelodeon says.
In his upcoming episode, "Mr. Krabs goes to Don for help as he tries to launch his line of frozen Krabby Patties. If anyone can sell crab in an ocean, Don can!" 
- His name is a parody of the Mad Men character, "Don Draper," whom Jon Hamm also played.