Billy was a Human male who resided in the town of Carbon Creek on Earth in 1957. He worked in a local mine and was a regular patron of Maggie's tavern, the Pine Tree Bar and Grill, where he often played pool.
When Vulcan visitors T'Mir and Mestral first visited the tavern, Mestral played a game of pool with Billy in order to earn currency, with T'Mir reluctantly agreeing to socialize with Billy if he won. Despite never having played the game before, Mestral easily beat Billy with his superior knowledge of geometry. Billy later became one of numerous friends Mestral made in the town. He was going to a baseball game that Mestral couldn't attend. (ENT: "Carbon Creek")