GAY is a female Tentacruel captured by Baba en route to Cianwood Island.
Her nickname GAY refers to being happy, homosexual or rubbish. This continues the tradition of Baba trying to use her Pokémon's nicknames to spell out rude or inappropriate messages.
GAY rarely saw battle and never gained a level. When the Vietnamese Crystal game encountered a bug, she was deleted in the reset. She was later recovered when another version of the save file was found.