Virgil is a runaway slave belonging to an ancestor of Charles Montgomery Burns. Yes, the Simpsons have a black member of their family. He appeared in Season 21's The Color Yellow, in which a number of extended Simpson family members appeared. However, the episode (and Virgil) created some continuity problems for the show, as it contradicted previously existing family history. In his later years, after escaping the slave trade to Canada, Virgil appears to look more and more like Homer.