"During the migration south and west, the settlers encountered the French immigrants of New France (from which Kentucky, Arkansas, Louisiana, Missouri, Mississippi and western Tennessee originated), and the French accent itself fused into the British and Irish accents. The modern Southern dialects were born." -
Southern American English - Wikipedia, the free encyclopedia
I'm not sure why you associate a perfectly classy word with a brothel?
As for laziness from hot weather, it's a joke brought up by some of my southern black friends, as in, "it's too hot to talk right, so i talk short."