If you come from a small, quiet family and your friend takes you to meet their large, talkative family, you might feel like a fish out of water — a bit awkward and out of place — until you find out they all share your love of hockey!
Out of its usual watery environment, a fish will eventually die, but first it'll be extremely uncomfortable — just like a person outside their familiar environment might feel. The expression fish out of water, used in this figurative way, has been around for hundreds of years. It may have been inspired by Geoffrey Chaucer, who compared a monk who doesn't follow the rules to a fish that is waterless in The Canterbury Tales.