Apparently there are only courtesans.
"They Call Me Carpenter"
Upton Sinclair
All the sentimental virtues seem to flourish spontaneously, even in the hearts of his courtesans: and though he holds up a true ideal of fidelity in love and loyalty in friendship, yet the chief practical lesson that seems to be suggested is the necessity of overcoming the restraints imposed by prudence and conscience on the indulgence of natural inclination.
"The Roman Poets of the Republic"
W. Y. Sellar
courtesans were licensed in order that their trade might help to replenish the imperial treasury.
"Women of Early Christianity Woman: In all ages and in all countries, Vol. 3 (of 10)"
Alfred Brittain Mitchell Carroll