Moore's insinuation in The Killing Joke of the Joker undressing Barbara and photographing her was that she was raped while she was bleeding from an abdominal wound. There's nothing more explicit than that insinuation. It is a very hard core story from that perspective.
I was aware that some readers of the book objected to the Batman sharing a laugh with the Joker at the end. But the joke itself and the laughter is a switch from the gritty realism of the Batman offering to rehabilitate the Joker, poised on the edge of knowing that they were inevitably going to kill each other otherwise, to symbolism. The joke is a symbol, the laughter is a symbol, and the playing card on the back jacket is a symbol: that, at tne end of the day, the two characters have manifested their grief in fundamentally similar ways (whereas Gordon is stronger than them both).
Its a testiment to Moore's remarkable skills that we're still talking about this comic, decades later. Moore might say, as he has somewhere, that its just a Batman story. But it isn't. Its a defintion of the two characters. Its a psychological examination of how people react to the world's random injustice (Batman, the Joker, Gordon). Its Nietszchean and amoral and nihilist. Its a fucking clever read.
But please, no more gags about a woman being anally raped. I know girls who have been raped. Its just not funny.
