Hot on the heels of The check-up, maybe this is a reverse variation on the “pull back and reveal”, only with the joke on the subject, not the object (or something—how would I know, I just do fieldwork on Daoist ritual):

A medium is holding a séance. With a group of genteel clients assembled around her table, lights dimmed, she begins, softly,
“Now everyone—before we begin, I just want to ask you, has anyone here ever seen a ghost?”
They all bow their heads in silence, but one geeky chap sticks his hand up and goes perkily,
“I have!”
They look curiously at him. He goes on,
“And—what’s more—I’ve fucked one!”
Incredulous, the medium asks him,
“What? You mean… you’ve… fucked a ghost?”
Disconcerted, he pauses. Then, nonchalantly:
“Sorry—I thought you said goat…”