|This is not a woman: Bando Tamasaburo
So Gay:sha does indeed differ from Geisha. Whereas all fans of Arthur Golden know that Geisha learn their trade at an okiya, there is no school for Gay:sha. It's not a calling but more like a revelation, albeit a very gradual one.
The mizu-age, er, ceremony, as fans of The Book will recall, is the defining moment of the geisha's careeer. Mizu-age is the euphemism for her de-flowering. It is the point, like a bat mitzvah, when she graduates from maiko [apprentice] to geisha, the professional adult.
The literal translation of the term is "landing, unloading, a catch, takings," which collectivley are quite revealing. The poetic connotation is of water flowing. Reverse the characters (excluding the most simple, which is a Japanese letter serving a grammatical, not semantic, purpose) and you have yoosui:
or "pumping water" [as in from a well], whose english connotations we'll tactfully skip over.
By contrast, there's no such ceremony marking the transition from maiko ["dancing youth" or "flitting youth"]
to a gay:sha. As Gay:sha said earlier, one discovers these things retrospectively, and in slow motion.
In fact the notion of a gay:sha withholding his virginity for the, er, client is rather far-fetched for the urban gay boy who's even remotely attractive. In fact inexperience would likely be a liability; to wit, early Imperial Rome's unoffical wag and master of the bon mot, Martial:
Why won't I marry you? You're a blue stocking.
And my cock is educated something shocking!
Epigrams, Book 11.19