Immoral??? We are punting F F Sake..
if the guy wants to secretly video his session for his own use ... so what.
I say
Even if the girl doesn't allow being filmed? Would you stick your cock up her ass if she didn't offer anal? And if she does allow being filmed but for a price, yet you'd rather film covertly without having to pay - well I just believe in treating people how you'd like to be treated. I hope it doesn't happen but imagine a prossie steals £20 from you, it's not right. I think we always pay the price for doing something dishonest. Karma.
Anyway, it's already been pointed out, filming private acts without permission is voyeurism and a criminal offence since 2003. You can receive up to 2 years in jail and your name on the violent and sex offenders register.
Goes both ways, prossies shouldn't film punters without permission. You say it's for your own use, a prossie might say it's for safety, but what if it does fall into the wrong hands? Karma will get the cheating, bad prossies and karma will get the cheating, bad punters. Sooner the better for all.