The quote is from Porgy and Bess isn't it? So this is Negro dialect. As I remember, whoever said it is trying to persuade the other person not to commit himself to marriage, but to have affairs. That's a very prosaic way of putting it. My advice is to look at the libretto of Porgy, which must be available on the web, and look into the circumstances. Sometime is not standard in BE as an adjective, but the sentence is very understandable.