Look, if scary horror-movie violin music started playing whenever a sociopathic rapist walked in the room, we wouldn’t have a rape problem.
But it doesn’t.
And rapists are very charming people. That’s what they do. The most successful manipulator will convince you that you are safe in their arms until it is too late. A successful manipulator will convince you that you don’t need pepperspray or karate or your cell phone. A successful manipulator will make you feel good about yourself and them. A rapist with big red horns and scaly green skin who jumps out and yells “SWIGGITY SWAPIST I’M A RAPIST” is an unsuccessful rapist.
If it was that easy to tell who the rapists are from a distance, we wouldn’t have a rape problem.