Prostitutes are shown dealing with costumers and inviting them but nothing more is shown.
Sex is implied but not shown.
A father sells his daughter into prostitution.
A man rapes Oharu but it happens off screen and not shown.
Several nonsexual references to prostitutes.
A woman tells a story of an old man who revealed an old prostitute's face to a young man and asked him "Would you sleep with this woman?".
Oharu is scolded for "sleeping with a man without our consent".
A man tells another man that he has come for a concubine for his lord, as the lady's illness "has left her barren", and the family has "no heir". He mentions that they gathered some country girls, but they were "not to his (the lord's) liking". They gather a large group of women for inspection for the role - eventually, Oharu is chosen and sold by her family (she isn't entirely happy about the situation).
Oharu is sold into prostitution by her father to pay off his debts, but is sent home for failing to do her job.
Oharu decides to become a nun, but is kicked out of the nunnery after being found with a man - she isn't listened to, begging the head nun to let her stay and telling her that "he was trying to rape me." She then becomes a prostitute, but fails at that as well (nothing explicit shown).