I'm trying to remember a very specific (old-fashioned but not completely uncommon term) for a man who behaves in an ungentlemanly way towards a romantic partner --for example, a young man who boasts crudely to his friends about his liaison with a young woman who had asked him to keep it a secret.
The word is not lout or churl or chauvinist. The connotations are of someone who is ungrateful and immature --someone who is unappreciative of the sexual favors they are receiving.
Sample Sentence: I didn't mean to be a _____ when I insulted the breakfast you brought me in bed this morning.