'After the Ball' is nothing spectacular of a movie. While it's one minute running time we can witness a servant helping to undress another woman before the bathing. Then the servant pours woman over with a water (that seems like an ash, but actually it is colored water, because Melies thought that regular water mightn't show on the film), and then helps to dry her.
I guess it might get some men's blood boiling while thinking about two women at the same room. But no, don't get your hopes very high. It's not a porno, not even very erotic.
'After the Ball' could also be called first movie that was made just because to be edgy, shocking, to offend some sort of people. Maybe Melies wanted to make a film for the sake of provoking. Here writer couldn't say, because he himself lacks more knowledge about that particular film by the early auteur.