Lou Seal is an official mascot of San Francisco Giants. He is a seal because of the San Francisco Seals, a former Pacfic Coast League Double-A (now Triple-A) team, one of the most sucessful minor league baseball teams. His name is a play on the word Lucille (however, officially he is a male and the person playing him is a man). He made his debut in 1996.

Born on July 25, 1996, Luigi Francisco Seal has been a regular part of all Giants home games, as well as numerous events in San Francisco and around the United States, ever since. Although his name (a play on the name Lucille) is a bit ambiguous, he is indeed officially male and the person inside the costume is a man. Lou Seal is also a reference to the San Francisco Seals, the baseball club that was a mainstay of the Pacific Coast League from 1903 until 1957.