Published on "Advocate Men" August 1990
(A "black-tie affair" is one where gentlemen are expected to wear tuxedoes, and ladies ball gowns or evening gowns.
In other words, a high-class party.
And and "affair" is a relationship, a liason or romance of however long duration.
After a "black-tie" social-party, they are having a black-tie "affair", a sex-party.)