Is not that. In Japan sex work is legal as long as it does not involve paying for coitus between two persons that do not know each other. Anything beyond that is not legal, and the legal system in Japan is ruthless. Also, most of that business is involved with the Yakuza, so you don't want to get in trouble with them.
That's why soaplands and massage parlors exist, because they don't do "the full course". There are loopholes and such, but still most people decide not do risk it.
Is not so much a "virginity" issue, as much as "this dumb girl is gonna end up in jail and making the police close this place".
The AV note is wrong; AV means "adult video", so literally p0rn.
He is probably with the Yakuza, that's why he mentions he will get a cut from. If she is that unlucky, then he's also implying he can traffic her if she doesn't do what he asks.