Legal Question in Criminal Law in Ohio

Yes, if you engage in illegal activity -- or even if you appear to be. You're right to be cautious. It's possible to go to such a spa without doing anything illegal, and merely going there isn't a crime.

But your question suggests you plan to engage in behavior that's likely to cross this line. If so, you are putting yourself at risk. Many people don't know what's legal and what isn't. That includes many people who firmly believe that they do know. They're even less likely to know what will seem to be illegal if the authorities find out about it. Remember, they could find out about it later even if no one catches you in the act.

Bear in mind that legal trouble isn't the only kind you might find yourself in. Let's say the police show up and find no evidence you've committed a crime. The fact that you were there when they arrived could still get out, and could cause you both real harm and great embarrassment.