Like all the Anti-Fairies with their Fairy counterparts, Anti-Sparky resembles Sparky. But instead of having yellow and orange fur, he has blue and purple fur. Instead of being nice, he's evil (the title of his debut appearance episode suggests it and besides, all the Anti-Fairies are evil). Instead of having an orange collar with a star as a tag, he has a blueberry-colored collar with spikes around it and no tag. He also has bat wings, instead of having bee wings like Sparky; he has a black crown instead of a golden crown; he has spiky hair, instead of having it straight, he has a golden earring in his ear while Sparky hasn't and, instead of having blue-colored eyes, Anti-Sparky has red eyes (like most Anti-Fairies do). Instead of having a golden star on his tail like Sparky does, Anti-Sparky sports a skull on his tail.
Anti-Sparky also has a Cockney British Accent while Sparky doesn't.
Anti-Sparky is like your common Anti-Fairy. Only Foop seems to fear him due to his menacing look. He apparently hates it when someone raises their voice at him or corrects him. Foop was sick of his attitude and wanted to blast him only to get eaten in return, despite being evil, he does carry traits of his counterpart such as chasing a chew toy.
After seeing how much happiness Sparky brought to the Turner family, Foop decided to replace Sparky with Anti-Sparky in order to make them miserable. During his stay with the Turner family, Anti-Sparky constantly harassed them, destroying Mr. Turner's new grill, signing up Timmy to pick up trash, and injuring Mrs. Turner, causing her to have to stay in a full-body cast. He also harassed Foop, warning him to not look them in the eye or raise his voice and constantly threatened him. Once Foop finally gained the courage to speak up to Anti-Sparky, he retaliated by eating him. Later, when Timmy found out he wasn't the real Sparky, Cosmo kicked him, causing him to throw up Foop, the Johnsons, and their wands that he had eaten earlier. They soon poofed him back to Anti-Fairy World while Foop was punished by the Anti-Fairy Council for failing to complete the mission.
Due to Sparky's removal after Season 9, this makes "Man's Worst Friend" the first and last appearance of Anti-Sparky in the series.
Anti-Sparky is the first anti-fairy (other than Foop and the Anti-Fairy Council) to appear in the show since "Balance of Flour."
He is the only anti-fairy animal to appear in the show.