this law is the very definition of a thought crime!
Well, no, not technically, since a thought crime would constitute a crime based on one's thoughts preemptively before the action. Since no one has the ability to read minds in any way, it therefore can't be a thought crime.
People are not being criminalised for what they do (after all it's legal for conscenting adults to engage in S&M), they're being criminalised for what they're thinking about doing, which according to the law-makers is to inflict pain and torture on the unsuspecting public.
No, not really, not based upon the description. I would agree that they should be allowed to wear latex and flog each other to Yanni's greatest hits, for all they want. But it really isn't a thought crime, since the only way the authorities knew about such things was actual evidence and not their thoughts.
“Tu ne cede malis sed contra audentior ito"