We all have our own life's experiences, and I can only answer you in accordance with my own.
Jesus said "out of the abundance of the heart the mouth speaks" (Matt. 12:34), and that is how I genuinely know.
In other words, by simply listening to what comes out of a woman's mouth (the same principle applies to men), I'll know, soon enough, exactly what is in her heart.
I'm not trying to be funny or anything like that, but, in all honesty, if I can make it to the second conversation with a woman without her making sexually suggestive statements to me, then it's basically a miracle. And I'm talking about PROFESSING CHRISTIAN WOMEN.
Again, this is only my own experience. Hopefully, things are much different for other Christian men.