Kevin Uuxbridge was a grouchy old guy with sibilance problems that appeared in Star Trek The Next Generation season 3 episode 3, “The Survivors.” Unbeknownst to anyone, however, he was more than just another old man yelling at clouds, but a Douwd, a being of great power and special conscience; a conscience he demonstrated when, after his human wife Rishon was killed by an attack by a race of aliens known as the Husnock, he utilized that power to render the entire Husnock species extinct in a single moment, then created a simulation of Rishon and their former home to quietly resume his life.
When the Enterprise arrived to check up on the planetary colony on which the couple lived, Kevin, wracked with guilt, and grief, and most of all self-righteousness, acted like a total dick to Captain Picard and obstructed his attempts at investigation and rescue at every turn. He even forced Counselor Troi to listen to a dumb ice cream truck melody over and over until she went insane and had to be placed in a medically-induced coma so she wouldn’t read his mind and find out what he had done. Once the truth ultimately came out, rather than attempt to force Kevin to face justice for his massive and flagrant war crime, Captain Picard wisely pretended the Federation “had no law to fit his crime” and left him alone to wallow in self-pity.
And that would have been the end of Kevin’s story, had not Adam Pranica and Ben Harrison not found his voice and obnoxious personality funny enough to make their shockingly good impressions of him the single longest-running joke on their Star Trek podcasts The Greatest Generation and Greatest Trek. Ben and Adam’s take on Kevin has a thriving business in artisanal sex dolls (inspired by their characterization of the illusory Rishon as “a RealDoll”) and is extremely casual about threatening genocide, or recommending it as a course of action, all while underscored by actual ice cream truck music.