semen mixer

A Gay Pride fund-raising party or charity gala, where donations typically derive from wealthy, older gay men who attend in order to prey on the younger, poorer ones.

Only superficially resembling a party, these events tend more to emphasize social networking and jockeying for position within the local community. As the term implies, these events are often given over-the-top sexualized themes, if only to attract many attendees while simultaneously distracting them from the fact that there's no actual partying or sex going on.

The opposite of a semen mixer is a bachanal.

That party we'd heard about turned out to just be a semen mixer. It was like a box social from the 1930's combined with a women's sewing circle. We just left early and rented a movie instead.