Virgil "Bull" Sharkowski is the main antagonist of the Cartoon Network series My Gym Partner's a Monkey.
Bull is an African-American bull shark who is one of the bullies at Charles Darwin Middle School. He enjoys beating up smaller kids and stealing their lunches. His intimidating presence, however, is offset by a high-pitched, squeaky voice (sounding like Mike Tyson) that sometimes lessens the impact of his verbal threats. Despite being a bully, he also has a soft humane side that he doesn't usually realize he's revealing. Due to being an aquatic species, he wears water-filled headphones over his gills to help him breathe; when he talks, he'll stop as his gills suck up the water with a loud noise. His nickname is a mildly obscure reference to the fact that bull sharks are known to be the most aggressive of all shark species.