I'm amazed that the WTS is so against masturbation to begin with.
There is nothing - NOTHING - in The Bible that says masturbation is a sin. And this from a book that states a menstruating woman is unclean and so is everything she sits on.
The WTS avoids calling masturbation a sin, but repeatedly calls it 'an unclean habit'.
But that isn't in The Bible, either.
I see why any Christian group might be against sex outside of marriage, I get that (although don't agree), but what we have with the WTS is a cult-like group that says its members shouldn't masturbate.
Utterly ridiculous, especially for males. Sexually mature males continuously produce sperm. If a man isn't in a sexual relationship, then he gets a build-up of semen, aka 'blue balls'. Masturbation is pretty much as natural and common as blowing your nose.