Kevin (The Resurrection Casket)

Kevin was an extradimensional assassin hired by Drel McCavity. Physically he resembled a large furry black mass with large red eyes, and long arms and legs tipped with claws. Despite his fearsome appearance, he was often very polite to those he encountered, particularly the Tenth Doctor aned Rose Tyler, and often expressed remorse towards his victims. (NSA: The Resurrection Casket)