RORY: I’m assuming your locker’s in there somewhere also.
PARIS: Yup. Right behind Belle Watling.
Belle Watling is a character in the 1936 best-selling historical novel Gone With the Wind by American author Margaret Mitchell. Set in the south during the American Civil War, it won Mitchell the Pulitzer Prize, and was the #1 book of both 1936 and 1937 before being adapted into a hit film in 1939. It is still one of America’s favourite books, and is considered one of the Great American Novels.
In the novel, Belle Watling is a prostitute and the local brothel owner, so Paris is just saying that Summer is behaving like a whore by kissing Tristan so openly in public.